HomeMy WebLinkAboutSWP272266(8) i
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Drainage Improvement Plan
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NE loth Street/Anacortes Court NE
Storm System Improvement Project
Prepared for the City of Renton
by CH2M HILL
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Drainage Improvement Plan
NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Prepared for the City of Renton
by C112M HILL
March 1996
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This plan was prepared under the supervision of
a registered professional engineer
116868.A0
Contents
Section Page
1 Executive Summary 1-1
2 Introduction 2-1
Purpose and Background 2-1
Scope of Work and Authority 2-2
Criteria and Assumptions 2-2
3 Existing Drainage System 3-1
Trunk Drainage System Review 3-1
Trunk Drainage System Analysis 3-3
4 Alternative Solutions Development and Evaluation 4-1
Conceptual Solutions and Development and Screening 4-1
Screened Solutions Description and Evaluation 4-5
5 Selected Plan 5-1
Selected Solution 5-1
Future Land Use Evaluation 5-2
Implementation Priorities 5-3
Appendix A. Technical Memoranda
Appendix B. Hydraulic and Hydrologic Modeling Data—Input and Results
Appendix C. Cost Estimates
Tables
3-1 Existing Conditions Hydrologic and Hydraulic Analysis Results Summary 3-5
4-1 Conceptual Improvement Solutions Summary 4-3
4-2 Alternative 1B—Conveyance Improvements 4-6
4-3 Alternative 1B—Summary of Hydraulic Analysis Results 4-7
4-4 Alternative 3A—Conveyance Improvements 4-10
5-1 Selected Plan Hydrologic Analysis Sub-Basin Characteristics—Future Land Use 5-3
5-2 Selected Plan Future Land Use Hydrologic and Hydraulic Analysis Results 5-3
Figures
2-1 Project Location Map 2-5
2-2 Drainage Basin Boundaries and Existing Trunk Storm Drain System 2-7
3-1 Drainage Basin Boundary Map 3-7
3-2 Existing Storm Sewer Profiles—Main Trunk Line 3-9
3-3 Existing Storm Sewer Profiles—Lateral Connections 3-11
3-4 N.E. 10th/Anacortes Court City of Rented Top of Curb Elevations 3-13
4-1 Alternative 113 Plan—Trunk Storm Drain Improvements 4-13
4-2 Alternative 1B Profile—Trunk Storm Drain Improvements 4-15
4-3 Alternative 3A Plan—Trunk Storm Drain Improvements 4-17
4-4 Alternative 3A Profile—Trunk Storm Drain Improvements 4-19
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Section 1
Executive Summary
This drainage plan summarizes the results of drainage system investigation, analysis, and
solutions development to resolve existing flooding problems in a tributary trunk drainage
system within the Honey Creek drainage basin, City of Renton. The drainage basin study area
consist of approximately 63 acres, and is roughly bounded on the north by Sunset Boulevard,
on the east by 138th Avenue SE, on the south by NE loth Street, and on the west by Union
Avenue NE. Solutions to existing flooding problems along the trunk drainage system are
identified, with particular focus on those improvements that will eliminate frequent flooding
within the upstream portion of that drainage system in the area of NE loth Street and
Anacortes Court NE.
The plan findings validate prior preliminary drainage system assessment work performed by
the City and documented flooding within the drainage system. It presents the alternative
improvement solutions considered to resolve those flooding problems and provide a level of
protection consistent with current City of Renton standards and design criteria.
A total of eight conceptual solutions were initially evaluated. Those solutions included
options for increase in size of the trunk drainage system, bypasses within the drainage
system, possible diversions to adjacent drainage systems, and surface and sub-surface
detention storage. Based on review of those options with the City staff, two system-wide
improvement solutions were selected for further evaluation. Those included Alternatives 1B,
Anacortes Avenue NE Bypass Trunk Storm Drain, and Alternative 3A, NE loth Street
Detention Pond and Reconnection with Existing Trunk System. Those solutions are
illustrated on Figures 4-1 and 4-3 in Section 4 of this report. Technical feasibility,benefits
and potential impacts, and estimated implementation costs were evaluated for each
alternative. After review of results of that assessment with City staff, Alternative 1B was
selected as the preferred solution for implementation.
Alternative 1 B consists of the following drainage system improvements in order of their
recommended priority for implementation:
1-1
1. Replace the existing siphon located south of Sunset Boulevard in Whitman Court NE
with a 36-inch storm drain, and connect that pipeline to both existing Honey Creek
dual corrugated metal pipe arches (CMPAs) with a reinforced concrete junction
structure.
2. Install a new 30-inch bypass storm drain in Anacortes Avenue NE and in NE 1 Ith
Street, and with connections to the existing trunk and lateral storm drainage system in
NE IOth Place and NE IOth Street.
3. Install the remaining 30- to 36-inch replacement trunk storm drain through the apart-
ment complexes along the north-south alignment of Whitman Court NE, and connect
to the improvements described in priority 1 and 2.
The total implementation cost (exclusive of engineering and administrative costs) for imple-
menting the selected plan project improvements is estimated to be $560,000.
The benefits provided by this improvement will be a significant increase in the level of flood
protection to the entire drainage system (from less than 2-year to a minimum of 25-year level
of protection). The potential impacts of this option include a significant (approximately 3-
fold) increase in peak design flows delivered to the downstream Honey Creek system that
could affect downstream flooding along the Honey Creek drainage system or have other
associated impacts (e.g., erosion/sedimentation, habitat degradation). Evaluation of these
potential impacts should be considered in the succeeding phases of project implementation.
1-2
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Section 2
Introduction
Purpose and Background
This report summarizes the results of the drainage analysis and alternative improvement
solutions evaluation for a trunk storm drainage system within the Honey Creek Basin, City of
Renton. The location of the drainage basin evaluated for this project is shown in Figure 2-1.
In addition to drainage from areas within the City's jurisdiction, it includes some areas within
Unincorporated King County. The trunk storm drainage system evaluated begins at NE 10th
Street and 138th Avenue SE (Duvall Avenue NE) and discharges to a storm-sewered segment
of Honey Creek south of the intersection of Sunset Boulevard and Whitman Court NE. The
combined storm system outfalls to the Honey Creek stream channel northwest of the
intersection of NE Union Street and Sunset Boulevard. The location and extent of the trunk
drainage system evaluated, and the drainage basin and subbasins contributing to this system
are shown in Figure 2-2.
Recurring flooding problems have been reported and documented in Anacortes Court NE and
the intersection of this cul-de-sac with NE 10th Street. Portions of the properties along Ana-
cortes Court NE are at lower elevations than the street and curb. When flooding has
occurred, the flood waters have inundated the street and several of the properties and houses
in the vicinity by overflow from the street and/or through direct hydraulic connections to
existing private drainage systems. The City's Storm Water Utility Engineering Section has
previously collected data on the extent and location of the flooding, and has summarized the
probable causes.
The trunk storm drain system downstream of Anacortes Court was inspected by the City in
1992. A root intrusion problem was identified during this inspection and subsequently
remedied. The City's Maintenance Division placed this storm system on the annual mainte-
nance program to clean on a periodic basis. The trunk storm drain was subsequently evalu-
ated in a preliminary hydrologic and hydraulic analysis by the City. The evaluation indicated
that the majority of the existing trunk storm drain system appeared to be undersized and may
need to be replaced with larger conveyance pipes to meet current City design standards. This
engineering study was initiated to validate the City's preliminary assessments and to identify
a preferred design solution.
2-1
Scope of Work and Authority
The scope of work for drainage system evaluation and solutions development in this study
was limited to the trunk storm drain serving the tributary drainage subbasin area between its
downstream connection to Honey Creek, south of the Sunset Boulevard and Whitman Court
NE intersection, and its upstream limit at NE loth Street and 138th Avenue SE. The scope
also included limited downstream hydraulic capacity evaluation for Honey Creek between
the trunk storm drain system connection and the Honey Creek stream channel outfall west of
NE Union Street.
The City's primary project goals addressed by the scope of work for this study phase of the
project include the following:
• Characterize (by field inventory) the existing trunk storm drainage system and
tributary drainage basin area.
• Determine the potential severity and frequency of flooding within the drainage area
served by the existing trunk drainage system (with particular focus on the Ana-
cortes Court flooding problem).
• Identify and evaluate alternative improvement solutions that minimize the flooding
risk and impact within the area served by the trunk drainage system (with particular
focus on the Anacortes Court flooding problem).
• Identify the potential flooding impact of additional development within the basin
and the additional improvements needed to mitigate that impact.
• Define the estimated improvements construction costs and prioritize solution com-
ponents for implementation.
C112M HILL was contracted by the City of Renton, under Contract Agreement No. CAG-95-
038, dated April 18, 1995, to perform Phase I,Analysis and Solutions Development for the
NE loth Street/Anacortes Avenue Storm System Improvement Project. The results of work
performed under that agreement are presented in this report.
Criteria and Assumptions
Criteria
The solutions evaluation criteria for this improvements plan are categorized by the land use
basis for hydrologic assessment, the level of service for flooding protection, and the
2-2
hydraulic considerations for sizing trunk drainage system improvements. The King County,
Washington, Surface Water Design Manual(the Design Manual),partially adopted by the
City, is the basis for the criteria applied within these categories. Technical memorandums
(TMs) 1-2 and 3-2 in Appendix A detail the specific criteria used to evaluate the existing
drainage system and the alternative improvement solutions. In summary, the following cri-
teria were used:
• The hydrologic criteria for the evaluation of existing condition subbasin runoff
were based on existing land use maps and an aerial photograph provided by the
City. Assumed future land use for the evaluation of improved trunk drainage sys-
tem performance was based on existing development for built-out subdivision areas
supplemented by land uses consistent with zoning for undeveloped or sparsely
developed basin areas.
• The minimum level-of-service criteria for conveyance improvements evaluation
was for containment of a 25-year, 24-hour design storm within the trunk drainage
system, with a 100-year protection level without flooding beyond the City right-of-
way.
• The performance criteria for detention system evaluation was for control of the
2-, 10-, and 25-year, 24-hour design storms, with downstream containment of over-
flows from 100-year discharges within the City right-of-way. For preliminary
assessment of subsurface detention storage alternatives, a 10-year event was used;
for modeling of screened alternatives, a 25-year event was considered with a check
of 100-year event downstream impacts.
Assumptions
Major assumptions used in the evaluation and solutions development stages were as follows:
• Unobstructed conveyance exists in the existing and improved drainage system
components.
• The small amounts of onsite detention storage provided in the existing drainage
system are not effective in providing appreciable downstream peak flow reduction
(i.e., not considered for modeling analysis).
2-3
• Flooding under existing conditions cause a reduction in peak flows that would
otherwise be delivered to the downstream drainage system (not reflected in the
existing conditions modeling analysis).
Order-of-magnitude construction cost estimates for drainage system improvements are based
on estimated material quantities and unit prices (1995 dollars), including excavation and
material and placement costs of new pipes, manholes, and control structures, and on surface
restoration consistent with existing conditions. The use of a trench box during pipe installa-
tion was assumed for all replacement or new pipeline reaches. No sheeting and shoring costs
are included as may be required in certain reaches with subsurface utilities conflicts or with
excavation limitations. The preliminary estimates of required costs for easement and land
acquisition use an assumed unit cost of $2.00 per square foot (based on information provided
by the City). That cost would need to be confirmed through a property appraisal process for
the affected properties. Contingency (20 percent), mobilization and general conditions
(10 percent), undefined costs (10 percent), and sales tax (8.2 percent) are applied to all esti-
mated project costs except land acquisition. Engineering and administration costs are not
included.
2-4
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Section 3
Existing Drainage System
This section summarizes the field reconnaissance, drainage system inventory and investiga-
tion, and the hydrologic and hydraulic analyses of existing land use and drainage system
conditions in the project area. Technical Memorandum (TM) 1-2 in Appendix A provides
additional details. Pertinent tables and figures from TM 1-2 are also included at the end of
this section (not referenced).
Trunk Drainage System Review
Data Review
The following data for the existing stormwater system was provided by the City, and was
reviewed and incorporated(as applicable) with this report:
• Storm Inventory Plan Sheets 5304 SE, 5303 SW, 5310 NW, 5309 NE
• Stormwater Attribute Sheets for the above plan sheets
• Zoning Maps for the above quarter sections
• Survey Control Network description, Surveying Standards, and a description of
monuments in quarter sections 5303 and 5310
• Listing of the existing drainage systems for the Honey Dew development area, and
corrected attributes for the system
• Various plan and profile sheets for portions of the sewerage and potable water pipe-
lines in the project area
• Site plan and storm drain utility information sheets for the Mission Hills and Arlin-
dale plat improvements
• SCS soil map for the project area
• 1:12,000 scale aerial photograph (July, 1990) of the project area
• City's preliminary runoff analysis, hydraulic modeling calculations and figures
including preliminary delineation of project basin and subbasins
3-1
• Internal City memorandum regarding flooding in the project area, including photo-
copies of pictures documenting flooding
Drainage System Investigation
After review of existing data, field inventory data needs were identified and field surveys
were performed to collect that data. The drainage basin and subbasin boundaries were field
verified, compared to the previous City analysis, and adjusted where needed. The resulting
63.3-acre drainage basin was divided into subbasins that correspond to significant runoff
inputs (typically at manholes or catch basins) to the trunk drainage system (Figure 2-2).
The existing trunk drainage system and selected laterals were surveyed to determine invert
and rim elevations, pipe sizes, and pipe material types. This information was also collected
for four catch basins to the south of.the project area in the Mission Hills subdivision. The
corrugated metal pipe arches (CMPAs) which convey flow under Whitman Court NE, the
downstream commercial development area, Sunset Boulevard, and Union Avenue NE to the
Honey Creek stream channel outfall were also inventoried. The inventory data is presented
in Table 1 and Figures 1, 2, and 3 of TM 1-2 (Appendix A).
Pipe lengths for the hydraulic model were initially determined from the City Stormwater
Inventory Map. Some pipe lengths taken from the map were considerably different from the
lengths in the City attribute data. To resolve this discrepancy, a field check was performed
by pacing off the distances between manholes and adjusting the pipe lengths accordingly.
Some pipe diameters at the inventoried catchbasins also differed from those recorded in the
City's attribute data. Table 2 in TM 1-2 lists the pipe diameters found in the survey and used
in the hydraulic model.
The following manholes and catch basins from the City attribute data could not be located
during the field survey:
• 14.C3-11 Structure may be buried
• 14.D3-1 Structure and pipe not found
• 14.D3-2 Structure and pipe not found
• 14.C4-4 Sewer manhole found, no stormwater structure found
In the Anacortes Court NE a sanitary sewer manhole was found at the location of 14,C4-4,
instead of a Type 2 stormwater catch basin. A Type 1 catch basin was found on each side of
Anacortes Court, as shown in Figure 4 of TM1-2 (Appendix A). The catch basin on the east
3-2
side of the street receives runoff from the street, and a private yard drain on the adjacent
property. The east catch basin drains to the catch basin on the west side of the street. The
west catch basin collects street runoff, and possibly roof drains from the adjacent properties.
The combined flow from the west catch basin drains to manhole 3 (14,C4-2) at the intersec-
tion of Anacortes Court NE and NE loth Street. The inventory data indicates a discrepancy
in pipe size between the west catch basin (8-inch) and manhole 3 (10-inch). This may be due
to inaccuracies with the pipe diameter measurements or a subsurface interconnecting struc-
ture not found.
Figure 4 of TM 1-2 also shows the surveyed spot elevations for the top of curb along Ana-
cortes Court, historically the location of the most severe flooding in the project area. The
yards of the adjacent properties typically slope downward towards the houses. The street
provides some storage of flood waters,but is limited by top of curb and driveway curb cut
elevations. Above the curb control elevations, excess stormwater runoff can overtop the curb
and flood lower lying properties and houses. The grate elevation of the private yard drain
connected to the east catch basins is below the elevation of the east catch basin grate; there-
fore, backflow to the adjacent property would occur initially before flooding of the street.
The data review and system inventory findings were used as the basis for the analyses of the
hydrologic and hydraulic conditions.
Trunk Drainage System Analysis
Hydrologic Evaluation
Hydrologic model simulation as the basis for peak runoff flow and volume estimates for
existing and future land use conditions was performed using Version 3.a of the WaterWorks
modeling program. The program uses the Santa Barbara Unit Hydrograph (SBUH) method
to compute estimates of subbasin runoff for each design storm.
The subbasins identified in the inventory process were planimetered to determine their total
surface area. Curve numbers representative of the percent impervious areas and soil types
and groundcover in pervious areas were based on the King County Surface Water Design
Manual (Design Manual), and were determined using the aerial photograph of the project site
and field reconnaissance data.
3-3
Times of concentration were calculated using the Waterworks Tc-calculator, internal to the
hydrologic modeling program. This calculator computes times of concentration for sheet,
shallow channel and channel flow, based on the methods described in SCS Technical Release
No. 55, consistent with the Design Manual methodology. The Waterworks input data is
presented in Table 3 of TM 1-2.
Precipitation for the area was determined using the Design Manual Isopluvial Maps. The
following 24-hour precipitation values were used in the corresponding storm event modeling
simulations.
• 2-Year Event: 2.0 inches
• 10-Year Event: 2.9 inches
• 25-Year Event: 3.4 inches
• 100-Year Event: 3.9 inches
The assumed distribution of design storm precipitation over the 24-hour storm duration was
the Soil Conservation Service (SCS)Type IA distribution presented in the Design Manual.
Results
The existing conditions estimated peak runoff, runoff volume, and unit discharge for the four
design storms for each subarea are tabulated in Table 4 of TM 1-2 (Appendix A).
Flows were combined and routed through the trunk storm drain reaches as part of the
hydraulic modeling. The cumulative flows from the subareas at selected locations along the
trunk drainage system are presented in the Hydraulic Evaluation, Results section below.
Hydraulic Evaluation
The existing stormwater trunk drainage system hydraulic capacity was simulated using the
WaterWorks modeling program. The hydraulic element of the program uses a backwater
computation approach consistent with the Design Manual methodology.
Each structure in the drainage system (manhole/subarea node) was input to the model with its
rim elevation, pipe inverts, and manhole bottom elevation. Pipe reach lengths were com-
puted by the model using each structure's coordinates (assumed coordinate basis). Hydraulic
roughness parameters for the pipelines were also provided as input. The model was then run
to establish hydraulic profiles (expected water surface elevations along the trunk storm drain)
3-4
for the computed design event peak flows. Technical Memorandum 1-2 summarizes the
basis and results of this analysis and should be referenced for further details.
The model was not able to properly simulate the siphon located at the downstream end of the
existing system (mh 10). Therefore, hand calculations were performed to estimate the tail-
water elevations at the upstream end of the siphon for a range of flows. These calculations (a
tabulation of energy losses that cause a rise in the hydraulic grade line elevations) are pre-
sented in Table 5 of TM 1-2.
The hydraulic grade line elevations calculated for mh 10 were used as the starting condition
for the model. The 2-year storm event generated partially submerged starting conditions of
the pipe at mh 10, while the 10-, 25- and 100-year events resulted in full submergence of the
pipe at mh 10. The hydraulic grade line elevation was set at 0.5 feet above the rim elevation
for each storm that caused complete surcharging of mh 10.
Results
The results of the hydrologic and hydraulic simulations are included in Table 6 and Table 7
of TM 1-2, and are summarized below in Table 3-1.
Table 3-1
Existing Conditions Hydrologic and Hydraulic Analysis Results Summary
Drainage 2-Year 10-Year 25-Year 100-Year
System Pipe Full Flow Event Event Event Event
Reach Size Capacity Max. Max. Max. Max.Flow
(by node) (in.) (cfs)* Flow (cfs) Flow (cfs) Flow (cfs) (cfs)
9 to 10 24 28.4 17.1 29.5 36.7 43.8
8 to 9 18 15.5
7to8 18 20.8 13.3
6 to 7 18 11.8 11.7
5 to 6 18 6.5 8.8 ,x
4 to 5 18 6.6 7.2
3 to 4 18 8.4 gip„
2to3 12 2.3
1 to 2 12 2.6 1.9 3.9 5.2 6.4
* Full Flow Capacity based on Manning Equation for uniform flow.
Shading indicates hydraulic grade line is above structure rim
based on backwater analysis.
3-5
Comparison of the uniform full flow capacities of each pipe reach with the maximum com-
bined runoff flows for the four design storms indicates that surcharging of pipelines will
occur for design events at or below the 2-year recurrence interval. The shaded boxes indicate
nodes where flooding of inlets is predicted to occur. As shown in the table, the inlets for
reaches from mh 2 through mh 8 would be expected to flood for the 10-, 25-, and 100-year
design storms assuming no restriction in the upstream trunk storm drain exists (modeling
assumption). Because that restriction does currently exist, flooding is typically confined to
the upstream reaches of the trunk drainage system(in Anacortes Court and NE loth Street
vicinity). Similarly, flooding is predicted for inlets in reaches from mh 2 to 3, 3 to 4, and 8 to
9 for the 2-year design storm. Manhole 3, and reaches 2 to 3 and 3 to 4, are adjacent to Ana-
cortes Court, the area where flooding frequently occurs.
City of Renton memorandums dated September 5, 1991, and October 14, 1994, address the
flooding at Anacortes Court NE and on NE loth Street. The frequency of the flooding is not
estimated in these reports, however based on the model results, it is likely that events at or
below a 2-year recurrence interval will cause inundation of this area.
Anacortes Court and the surrounding properties acts to store stormwater runoff, thus lower-
ing the peak flow being conveyed through the downstream drainage system. Storage of
stormwater in localized depressions and the dissipation of stormwater across relatively flat
areas is not accounted for in the model simulations. Therefore, it is likely that the model
results for existing conditions predict higher hydraulic grade line elevations than would
actually result downstream of Anacortes Court NE.
Problem Areas Confirmation
The findings of the existing conditions analysis supports the City's flooding reports and
conclusion that the majority of the trunk storm drain in the project area is undersized to meet
current design standards. The primary system deficiencies exist in the area of NE loth Street
and Anacortes Court NE, and at the east end of NE 10th Place. Manholes along the trunk
storm drain in the access road through the apartment complexes north of NE 1 lth Street were
also predicted to surcharge during all modeled storm events. Based on modeling results, the
trunk storm drain reach through Honey Dew Estates is estimated to provide flooding protec-
tion for events up to approximately a 10-year recurrence interval.
The next section addresses the alternatives for reducing flooding, either by improved con-
veyance, diversion or the use of stormwater detention storage facilities.
3-6
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Section 4
Alternative Solutions Development and Evaluation
This section summarizes the results of the conceptual solutions development and screening
for the project. It presents the alternative improvements considered, their feasibility, benefits,
potential impacts and comparative construction cost estimates. Technical Memorandum 3-2
(TM 3-2) in Appendix A provides additional details.
Conceptual Solutions Development and Screening
Eight alternatives were developed for the City to review and select two alternatives for fur-
ther analyses. For the initial screening process the level of analysis detail was limited; there-
fore, conceptual improvement needs should be considered as preliminary and subject to
further refinement. Order-of-magnitude cost estimates were developed for comparison of
alternatives. Actual implementation costs could be significantly higher or lower than those
preliminary estimates.
The following alternatives were presented to the City.
• Alternative 1—Conveyance
— IA: Trunk Storm Drain System Replacement
— 1B: Anacortes Avenue NE Bypass with Trunk Storm Drain Reach
Replacements
• Alternative 2--Sub-Surface Detention Storage
— 2A: Whitman Court and NE 11 th Street
— 213: NE loth Place
— 2C: Anacortes Court NE and NE 10 Street
• Alternative 3—Diversion
— 3A: NE 10th Street/North to Existing Creek and Arches
— 3B: NE loth Street/West to Union Avenue NE
— 3C: NE 10th Street to Mission Hills Development (with Sub-Surface storage)
4-1
A brief description of the alternatives is provided below. Table 4-1 presents a summary of
the alternatives using the following evaluation criteria.
• Technical feasibility
• Potential benefits
• Potential impacts
• Order-of-magnitude costs
Alternative I - Conveyance
Alternative 1 A, shown in Figure 1 A of TM 3-2, considers replacement of the entire existing
trunk system along its existing alignment with pipes sized to convey the 25-year design
storm, with added protection for the 100-year event. Preliminary hydraulic analysis for the
assumed trunk storm drain improvements shows that surcharging would occur at Anacortes
Court NE for the 100 year event. Most of the existing manholes along the main trunk line
would be upgraded to accommodate the larger replacement pipes. A concrete junction struc-
ture is proposed to connect the improved system to both of the existing 58-inch x 36-inch
CMPAs, and to split the increased peak flow between the two arch pipes
Alternative 1B, shown in Figure I of TM 3-2,considers construction of a new bypass storm
system in Anacortes Avenue NE and NE 1 lth Street,reducing the peak flow to the existing
storm system and the flooding at Anacortes Court. This would require upgrading the existing
system upstream of the bypass, and complete replacement of the existing system downstream
of the bypass (mh 6 to mh 10). As with Alternative 1A, a concrete box junction structure
would be installed at the downstream end of the system to connect to the existing CMPAs.
Manhole replacements would also be required.
Alternative 2 - Storage
The storage alternatives considered would allow the existing undersized trunk line to remain
in place by reducing peak flows throughout the system. Each alternative proposes to detain
the peak flow from the 10-year design storm in an underground storage tank, with controlled
release back to the trunk drainage system. Figure 2 of TM 3-2 shows the proposed location
of each underground storage tank (each is an independent alternative).
4-2
Table 4-1
Conceptual Improvement Solutions Summary
Technical Potential Order-of-
C Alternative FeasibilityBenefits Impacts Ma nitude Cost
s. .. . _. .,r._ .. ,. .
IA: Trunk Feasible. Possible inter- Significant improvement Increase in delivered Approximately
Replacement ference with sewer and wa- in flood protection to level peak flows to down- $510,000.
terlines. Downstream con- of the 25-year event. stream system. Con-
veyance would have to be Limited protection for the struction impacts within
evaluated. I00-year event. right-of-way and to pri-
vate property.
1B: Bypass w/ Feasible. Downstream Significant improvement Increase in delivered Approximately
Trunk Replacement conveyance would have to in flood protection to level peak flows to down- $560,000.
be evaluated. of the 25-year event. stream system. Con-
Limited protection for the struction impacts within
100 ear event. ri ht-of-wa .
,
RhU� a r ,,. . .. a.
2A: Whitman Ct. Feasibility may be limited Limited flood protection, Construction impacts Approximately
and NE I Ith St. by facility requirements, to level less than the within right-of-way. $830,000.
large volumes of storage 10-year event.
required and hydraulic
grades.
2B: NE IOth PI. Feasibility may be limited Limited flood protection, Construction impacts Approximately
by facility requirements, to level of the 2-year within right-of-way. $540,000.
large volumes of storage event.
required and hydraulic
grades.
2C: Anacortes Ct. Feasibility may be limited Limited flood protection, Construction impacts Approximately
NE and NE loth St. by facility requirements, to level of the 2-year within right-of-way. $350,000.
large volumes of storage event.
required and hydraulic
grades.
3A: To Existing Feasibility may limited Significant improvement Easement acquisitions. Approximately
Creek and Arches by existing creek topogra- in flood protection to level Potential impacts to the $325,000(includ-
phy,inter-jurisdictional di- of the 25-year event. existing drainage course ing estimated ease-
version issues,easement ac- Limited protection for the and wetland would need ment acquisition
quisitions and potential sen- 100-year event. to be evaluated further. costs).
sitive area impacts.
313: West to Union Infeasible for gravity con- Option not evaluated Option not evaluated Option not evalu-
Ave.NE nection. High costs of further. further. ated further.
pumping are prohibitive.
Additionally,interbasin di-
version is not desirable.
3C: To Mission Feasibility may be limited Significant improvement Potential impacts to Approximately
Hills Development by downstream capacities in in flood protection to level biofiltration swale and $600,000.
Mission Hills,legal issues of the 25-year event. restrictive drainage way
regarding diversion and Limited protection for the south of project basin.
existing system sizes and 100-year event
rades.
4-3
Alternative 2A would involve the construction of a 1.7 acre-foot underground storage tank
north of the intersection of Whitman Court and NE 1 lth Street. Alternative 2B considers a
1.1 acre-foot storage tank beneath NE loth Place, and Alternative 2C considers a
0.8 acre-foot storage tank east of Anacortes Court NE. The level of resulting peak flow and
flood reduction benefit of each alternative varies.
The storage alternatives are limited by the high cost of constructing underground structures in
the City ROW, and the amount of storage needed for the 10-year storm event. Based on the
assessment for to provide up to a 10-year level of protection, the volume needed for the
25-year storm event was considered to not be feasible for sub-surface storage.
Alternative 3 - Diversion
Diversion of stormwater runoff away from the existing drainage system was considered at
three locations in the project area. The three alternatives (3A. 3B, and 3C, and modifications
to 3A developed after the release of TM 3-1)consider diverting the runoff from sub-basins
12, 13, 14 and 15. This is a total of more than 40 percent of the project area, contributing
approximately 35 percent of the peak flow to the downstream system during the 25-year
design storm. With the diversion of this portion of this peak flow, the existing downstream
trunk drainage system would be adequate to provide a level of protection up to the 25-year
event. For these alternatives, the existing siphon located between mh 8 and mh 9 would
restrict flow and cause flooding for events greater than approximately a 10-year magnitude.
For the diversion alternatives, the siphon would need to be replaced with a 24-inch diameter
pipe to provide adequate capacity up to a 25-year design storm event.
Alternative 3A, shown in Figure 3A of TM 3-2, considers diversion of runoff to the north at
mh 2 to a natural drainage swale (within King County) that extends north to Honey Creek
(connects upstream of existing CMPA's). The diverted runoff from mh 2 would be con-
veyed by a culvert discharging to a level-spreader at the head of the existing swale. Runoff
from an additional subbasin area north of subbasin 15 would also contribute runoff to the
swale and downstream drainage system. Further investigation of this alternative indicated
that the diversion system alignment would not be feasible due to topographic constraints
(field verified). Based on discussions with the City, this alternative was modified to incor-
porate a detention pond on property north of NE loth Street, with the discharge pipe connect-
ing back to the existing drainage system at mh6. The modified alternative was selected by
the City for further consideration and is included in the Screened Solutions Description and
Evaluation section.
44
Alternative 313, shown in Figure 313 of TM 3-2, considers diversion of peak flows to the west
to the existing drainage system in Union Avenue, which runs to the to the south. This pro-
posed improvement would not be feasible for gravity connection due to the higher storm
drain system elevations along NE loth Street. Furthermore, an interbasin diversion of runoff
would be required. For these reasons this alternative was not considered further.
Alternative 3C, shown in Figure 3C of TM3-2, considers diversion of peak runoff in excess
of the existing drainage system capacity through Mission Hills (the new development south
of Anacortes Court NE)to the adjacent drainage basin. To reduce the potential impact to the
installed Mission Hill drainage system, sub-surface storage similar to Alternative 2C was
considered along with the diversion.
Screened Solutions Description and Evaluation
The eight alternatives presented in the previous section were reviewed by City staff. Two
alternatives were selected for further assessment for technical feasibility, hydraulic capacity
and flood reduction benefit, potential impacts, and refinement in layout and estimated costs.
The results of these analyses and modifications to the conceptual designs are presented
herein.
Alternative 1B: Anacortes Avenue NE Bypass Trunk Storm Drain
Previous reports of flooding and the modeling results show that flooding can be expected
most frequently in the area of Anacortes Court NE and NE loth Street. Alternative 1B,
shown in Figures 4-1 and 4-2, proposes to reduce the peak flow delivered to the existing
trunk storm drain between mh 3 and mh 6 resulting in reduced upstream flooding. Alterna-
tive I would consist of a bypass pipeline to convey runoff through a new storm drain pipe
aligned beneath Anacortes Avenue NE and NE 1 lth Street. This would also require upgrad-
ing part of the existing system upstream of the bypass, and the complete replacement of the
existing drainage system downstream of the junction point(mh 6). The bypass and existing
trunk storm drain improvements are listed in Table 4-2, and were sized to convey peak flows
for the 25-year design storm without flooding , with a check of 100-year event hydraulic
impacts.
4-5
Table 4-2
Alternative 1B - Conveyance Improvements
Average
Existing Replacement Depth to Length
Pipe Upstream Downstream Diameter Diameter Invert of Reach
Reach ID Node Node (in) (in) Elev. (ft) (ft)
Bypass System
2 mh2 A 12 18 6 225
A A B N/A 30 5 280
B B C N/A 30 9 400
C C 14.C3-13 N/A 30 12 300
14.0-13 14.C3-13 mh6 N/A 30 12 225
3 mh3 A 12 24 5 235
Existing Up rade
1 mh 1 14.D4-2 12 18 9 305
14.D4-2 14.D4-2 mh2 12 18 5 295
5 mh5 mh6 18 no change n/a 410
6 mh6 14.0-11 18 30a 9 180
14.C3-11 14.C3-11 mh7 18 30a 7 60
7 mh7 mh8 18 30a 6 120
8 mh8 mh9 18 36a 6 255
9 mh9 mh 10 24 36a 6 60
10 mh10 9.C8-21 2-12 36; 6 30
to arch 9.C8-21 arch 24 36' 6 85
'Me replacement diameter was determined using the Inlet Control Nomograph,otherwise,it was calcu-
lated using Mannin s Equation.
Feasibility
Alternative 1B is technically feasible. Hydraulic modeling of this alternative under existing
land use conditions showed maximum water surface elevations below the manhole rim ele-
vations for all events, up to and including the 25-year storm. While no trunk storm drain
manhole surcharging is indicated in the results of the 100-year design storm simulation, the
hydraulic grade line elevations along Anacortes Avenue NE and NE 10th Street(between mh
2 and mh 3) show that the lateral storm drain on Anacortes Court NE may surcharge. No
other flooding in the project area is expected during the 100-year design storm. The results
of the 25-year event modeling are presented in Table 4-3.
4-6
Table 4-3
Alternative 1B - Summary of Hydraulic Analysis Results
25-Year
Event
25-Year Structure Hydraulic
Element Full Flow Event Rim Grade Line
Pipe Reach Size and Capacity' Maximum Elevation Elevation
ID Type (cfs) Flowb(cfs) (ft) (ft)
Bypass System
2 18" RCP 11.4 7.6 412.47 407.75
A 30" RCP 19.9 13.9 410.74 406.78
B 30" RCP 19.9 17.0 409.29 406.03
C 30"RCP 24.3 19.5 416.08 405.20
14.C3-13 30" RCP 24.3 19.5 411.92 n/a
3 24" RCP 19.9 6.0 409.88 407.36
Existing Upgrade
1 Existing 12" 8.9 5.2 437.82 428.49
RCP
14.134-2 18" RCP 11.4 5.2 416.46 n/a
5 Existing 18" 7.5 3.4 413.58 404.23
RCP
6 30" RCP 44.4 25.4 411.92 402.48
14.C3-11 30"RCP 71.6 28.8 Paved Over n/a
7 30" RCP 71.6 28.8 404.81 399.40
8 36" RCP 98.3 34.0 399.82 395.12
9 36" RCP 83.6 35.8 395.58 392.97
10 36" RCP 45.1 36.5 394.85 392.02
arch n/a 391.08
'Full Flow Capacity is based on Mannings Equation for normal flow
b25-Year Event Maximum Flows are cumulative. See plan sheet for Alternative 1B to see network sequenc-
ing. Pipes provide additional limited protection for the 100-year storm event.
The bypass alternative would involve the removal and replacement of existing pipes and
manholes within the street right-of-way. Excavation depth would average approximately
6 feet, with a range of depths from 4 to 13 feet. The majority of the 900 foot bypass pipe in
4-7
NE 11 th Street and Anacortes Avenue NE would be 10 to 12 feet deep. The use of a trench
box should limit the extent of required excavation and area impacted. Sheeting and shoring
near the intersection of Anacortes Avenue NE and NE 1 lth Street may be required. The pro-
tection of parallel water and sewer lines downstream of mh 6 may require the use of special
trench shoring measures. The removal and replacement of the siphon downstream of mh 9 is
required along with the construction of a concrete junction box at the existing CMPA arches
(see detail on Figure 4-1).
Based on review of available plans, it appears that the bypass line could be constructed along
Anacortes Avenue NE without disrupting existing sanitary or water pipelines. Downstream
flow impacts and development area construction impacts could affect project improvement
requirements and costs.
Benefits/Potential Impacts
Implementation of this alternative would provide a significant increase in the level-of-pro-
tection from flooding for the study area. The upgraded system and new bypass were sized to
convey flows from the 25-year storm (with additional limited protection in the 100-year
event) to the downstream Honey Creek CMPAs.
Improvements to the existing system could potentially impact the downstream system
through the delivery of higher peak flows (approximately three fold increase in peak flows as
compared to existing conditions for a 25-year event). Peak storm flows are presently being
controlled by upstream flooding, ponding and runoff to other basins, whereas an improved
system would convey this runoff at a higher peak rate directly to the downstream Honey
Creek drainage system.
Temporary construction impacts to roads,utilities and some private property in the Honey
Dew Estates development would also occur with the implementation of this alternative.
These may include the following temporary disturbances:
• Roadway access restrictions
• Utility disruptions for relocation
• Increased turbidity for flows discharging to Honey Creek
• Construction equipment disruption
4-8
Estimated Cost
Major construction cost items for Alternative I include the bypass pipes and existing storm
drain replacements listed in Table 4-2, five 60-inch diameter manholes, seven 72-inch diam-
eter manholes, and the junction structure at the CMPAs. The preliminary estimate of the
construction cost for this alternative is approximately $560,000. This cost estimate is sum-
marized in Table C-1 of Appendix C.
Alternative 3A: NE loth Street Detention Pond and Reconnection with
Existing Trunk System
Alternative 3A, as shown in Figures 4-3 and 4-4, proposes to reduce the peak flow delivered
to the existing stormwater trunk system by diverting runoff from subbasins 12, 13, 14 and 15
to an excavated open detention pond north of NE loth Street along the east fence line of the
Anacortes Avenue NE properties. Originally Alternative 3A proposed to use an existing
drainage swale to divert flow to the north to Honey Creek. However, further analysis and
field reconnaissance after the release of technical memorandum TM 3-2 indicated that using
the existing drainage course would not be feasible due to topographic constraints.
Based on discussions with the City, Alternative 3A was modified to include a 1.8-acre-foot
surface detention pond and reconnection to the original drainage system. The proposed
detention pond consists of an 8 foot deep (3 foot active storage depth) trapezoidal pond with
surface dimensions of approximately 250 feet by 150 feet, as shown in Figure 4-3. The
maximum pool elevation of the detention pond would be 406.5 feet. This elevation was
established to maintain flood elevations below the lowest catch basin rim elevation at Ana-
cortes Court NE (El. 409.0) for the 25-year design storm.
The existing stormwater pipe between manholes 2 and 3 would be replaced with a larger
pipe, sloping towards mh2. This pipe would convey the runoff from subbasins 13 and 14 to
the pond. The pipes between mh 1 and mh 2 would be upgraded only from the intermediate
manhole (mh 14.D4-2)to mh 2, and would convey the runoff from subbasins 12 and 15 to
the pond.
The pond was sized to detain the peak runoff from the collection areas described above. It
would also collect surface runoff from a new area currently outside of the subbasin bounda-
ries. This 4.5-acre area north of subbasin 15 and east of the pond is labeled "new" on the
plan sheet for Alternative 3A (Figure 4-3).
4-9
The proposed pond would release a peak flow of approximately 4.5 cfs to a new pipe reach
leading back to Anacortes Avenue NE. The new pipe would pass along the fence line
between the third and fourth properties north of NE loth Street, connecting to a new manhole
in Anacortes Avenue NE. The new manhole would also collect runoff from subbasin
10 conveyed through a replacement pipe from mh 4 to mh A. The combined runoff would be
conveyed north in a new pipe line in Anacortes Avenue NE and NE 1 Ith Street to mh 6,
where it would connect to the existing trunk storm drain system. No further upgrades of the
existing storm drain system would be required, except for the replacement of the siphon near
the downstream end. The siphon improvement calls for a 24-inch replacement pipe and the
replacement of one manhole.
The pipe improvements, sized to convey the 25-year design storm and provide limited addi-
tional protection for the 100-year design storm, are listed in Table 4-4.
Table 4-4
Alternative 3A-Conveyance Improvements
Replace- Average
Down- Existing ment Depth to Length of
Pipe Reach Upstream stream Diameter Diameter Invert Elev. Reach
ID Node Node (in) (in) (ft) (ft)
14.134-2 14.134-2 mh2 12 18 5 295
3 mh3 A 12 24 5 240
A A mh2 12 24 7 225
2 mh2 pond N/A 24 8 50
4 mh4 B 18 18" 7 215
F F B N/A 24 7 160
B B D N/A 24 8 200
D D C N/A 24 12 200
C C E N/A 24 13 300
E E mh6 12 24 11 230
siphon mh9 mh 10 2-12 1 24 1 9 1 90
'New grade is opposite to existing grade.
Replacement diameter determined using Inlet Control Nomograph. All others calculated using Mannings
Equation for uniform flow.
Feasibility
The Alternative 3A diversion and detention alternative was found to be technically feasible
based on modeling evaluation. The hydrologic function of this alternative was modeled us-
ing the HEC-1 Flood Hydrograph Package program. This was done to correctly simulate the
4-10
effects of the detention pond flow routing and the combining of flows downstream
(WaterWorks Version 3a would not correctly simulate). The subbasin runoff peak flow
results of the HEC-1 model were compared to the WaterWorks model to check compatibility
of the two models. The results agreed closely. The HEC-1 model was then run for the 25-
year event with the pond routing parameters to confirm the adequacy of the assumed pond
size. The results of that analysis confirmed the adequacy of the 1.8 acre-foot pond size for a
4.5 cfs maximum release rate under 25-year event design storm conditions (existing land use
conditions). The HEC-1 model input and output files are included in Appendix B.
Based on review of available plans, it appears that the pipeline connecting the pond to the
existing system at mh 6 could be constructed along Anacortes Avenue NE without disrupting
existing sanitary or water pipes.
Benefits/Potential Impacts
Implementation of this alternative would provide a significant increase in the level-of-pro-
tection from flooding for the study area. The pipeline improvements to the storage pond and
from the storage pond to the existing system were sized to convey flows from the 25-year
storm.
A benefit derived from this option, as compared to Alternative 113, is that the downstream
drainage system (the CMPAs and Honey Creek) would not be subject to increased peak
flows. The evaluation of the need for improvements downstream of the CMPA connection
were beyond the scope of this study.
Construction of a detention pond would have some potential impacts. Approximately
9,000 cubic yards of soil would be excavated to construct the pond. A location would be
needed for disposal of the excavated soil. There is also a potential for groundwater table
draw down due to the pond excavation and outlet pipe installation. This may have an impact
on a possible wetland area (assumed from topographic map and field reconnaissance)to the
north of the proposed pond location. Groundwater dewatering also has the potential to cause
settlement of adjacent land. A geotechnical investigation would be needed to determine the
existing groundwater level and potential effects of a detention pond.
The land needed for the pond would likely require purchase from a private property owner.
Approximately 1 acre of land is anticipated to be needed for the pond, buffer area, and access
road. Based on land values of developed properties nearby, purchase cost for 1 acre may
range from approximately $100,000 to$200,000. The City should consider obtaining a mar-
4-11
ket analysis from an appraiser to more closely estimate the potential land cost, if it wants to
pursue this alternative. There are also interjurisdictional issues related to the construction of
a detention pond outside of the City of Renton boundaries that may have to be resolved
before the project could be further developed.
A permanent utility easement would be needed for construction and maintenance of the new
pipe that would cross private property to go from the pond to Anacortes Avenue. Temporary
construction impacts to roads, utilities and some private property in the Honey Dew Estates
development would occur with the implementation of this alternative. These impacts may
include the following temporary disturbances:
• Roadway access restrictions
• Utility disruptions for relocation
• Increased turbidity for flows discharging to Honey Creek
• Construction equipment disturbance
Estimated Cost
Major construction cost items for Alternative 3A include the existing storm drain replace-
ment pipes and additional reconnection pipes listed in Table 4, four 60-inch and two 48-inch
diameter manhole structures, a discharge structure,pond excavation haul and disposal, and
land/easement acquisition costs. The preliminary estimate of the implementation cost for this
alternative is approximately $520,000. This cost estimate is summarized in Table C-2 of
Appendix C.
4-12
FIGURES 7 `1 / SIZE Ll 2
TABLE
TITLE
PRESENT LOCATION AND STATUS :
GENERAL DESCRIPTION AND IDENTIFYING CHARACTER:
PRINT OUTSIDE INSIDE
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Section 5
Selected Plan
This section identifies the drainage improvements plan selected by the City of Renton for
trunk drainage system modifications within the project area. It present the results of a future
land use evaluation to define additional possible improvement needs under full build-out
conditions within the basin. Recommended priorities for implementation of improvements
are also summarized.
Selected Solution
Based on consideration of the screened solutions presented and evaluated in Section 4, the
City of Renton selected Alternative 1B, Anacortes Avenue NE Bypass Trunk Storm Drain as
the preferred design solution for implementation. Section 4 describes the improvements pro-
posed for this alternative. Figures 4-1 and 4-2 present preliminary plan and profile align-
ments for the proposed improvements. Recommended sizes for the new bypass storm drain
and required replacement piping within the existing trunk drainage system are shown in
Table 4-2. Alignments and sizes should be validated for any modifications that may occur
with the final design of improvements.
Once fully implemented, this solution will provide flood protection to a minimum 25-year
level of protection in accordance with current City standards and design criteria. If phasing
of project construction is required to meet funding limitations, some interim benefit in flood
protection may be gained through sequencing of improvements consistent with the priorities
identified below.
The estimated implementation cost of all improvements associated with this solution is
$560,000(1995 dollars, exclusive of engineering and administrative costs required for final
design, bid, and construction).
5-1
Future Land Use Evaluation
The selected solution improvements were evaluated under future land use conditions pro-
jected within the basin area to assess their adequacy to provide the targeted level of flood
protection with additional basin development. The King County Surface Water Design
Manual and City of Renton stormwater control regulations require that increases in peak
runoff greater than 0.5 cfs caused by new development be controlled by on-site
retention/detention systems. Therefore, the proposed storm system improvements should not
be required to convey increased flows from new development. After discussion of this with
City staff, a conservative approach was used for analysis by assuming that no detention is
provided for future development within the drainage basin.
All subbasins except 12 and 15 are presently at full build-out conditions. Therefore, only the
land use determinations for these two subbasins were modified for the future land use analy-
sis. Upon the City's recommendation, the proposed land use designation used for subbasins
12 and 15 was "residential, developed at a density of 8 dwelling units per acre." The land use
for the church and parking lot in sub-basin 15 was assumed to remain unchanged.
Hydrologic and hydraulic model simulation of the entire drainage system using the future
build-out condition assumptions was performed in the same manner as described in Section
4, Hydrologic and Hydraulic Evaluation. Table 5-1 presents the future land use data used for
subbasins 12 and 15. All other subbasin parameters remained unchanged.
The results of the hydrologic and hydraulic modeling for future land use conditions are
shown in Table 5-2. Without retention/detention to attenuate the peak flows from future
development in subbasins 12 and 15, flooding at manhole 1 is predicted to occur for the 25-
year storm event. Likewise, manholes A, B, 2, 1 and 3 are projected to flood during the 100-
year storm event. If stormwater peak flow controls are not provided for future development,
then the pipe segment between manholes 1 and City ID 14,134-2 should be replaced by an 18-
inch RCP. No other improvements should be required to provide a system-wide 25-year
level of flooding protection for those conditions. Further detailed evaluation would be
5-2
required to confirm that flooding under 100-year event conditions would stay confined to the
City road right-of-ways.
Table 5-1
Selected Plan H drolo 'c Analysis Sub-Basin Characteristics-Future Land Use
Area Percent Impervious Percent Time of
Subbasin (ac) Impervious CN Pervious Pervious CN Concentration'(min)
12 12.8 60% 98 40% 86 19.0
15 5.0 79% 93 21% 86 19.0
a Time of concentration is defined for flow in the sub-basin to the collection node.
Table 5-2
Selected Plan Future Land Use Hydrologic and Hydraulic Analysis Results
Trunk Drain- 25-Year 100-Year
age System Structure 25-Year 2-Year Event 10-Year Event Event Event
Reach(By Rim Event Hydraulic Hydraulic Hydraulic Hydraulic
Node Elevation Maximum Grade Line Grade Line Grade Line Grade Line
Number) (ft) Flow'(cfs) Elevation(ft) Elevation(ft) Elevation(ft) Elevation(ft)
10 to jnctn. 394.85 40.8 389.18 390.54 392.29 393.28
9 to 10 395.58 40.8 390.47 390.86 393.53 395.02
8 to 9 399.82 40.0 395.08 395.10 395.09 396.40
7 to 8 404.81 33.7 398.31 398.61 400.75 401.30
6 to 7 411.92 30.4 401.99 402.43 404.41 405.42
C to 6 416.08 24.5 404.37 405.23 406.71 408.68
B to C 409.29 22.0 405.34 406.09 407.98 MaNNOM
A to B 410.74 18.1 406.20 407.04 409.24
2 to A 412.47 12.2 407.70 408.46 411.40
1 to 2 437.82 8.9 428.02 431.64
5 to 6 413.58 3.4 403.90 404.08 404.86 406.07
3 to A 1 409.88 6.0 407.06 ± 407.18 409.47 IMMAM
' Cumulative flow. Dispersal and localized storage are not taken into account.
b Hydraulic grade line elevation is above the structure rim elevation. The program sets the HGL at the structure at
0.1 feet above the rim to allow for ponding or bypass.
Implementation Priorities
If all improvements are not able to be fully implemented as a single project, the following
priorities for implementation should be considered to maximize the interim flood protection
benefits provided:
5-3
1. Replace the existing siphon between mh 9 and mh 10 with a new storm system pipe,
extend the new pipeline to the existing CMPAs, and construct the junction box.
2. Install the Anacortes Ave. NE bypass storm drain system and lateral storm drainage
system connections.
3. Install the remaining replacement trunk storm drain between mh 6 and mh 9.
The benefit provided by this phased approach (if necessary) should be a measurable
improvement in the level of flood protection provided to the upstream drainage system. This
will result since the capacity of the existing system downstream of mh 6 will be effectively
increased with additional allowable headwater depth at mh 6 (operates under inlet control)
prior to upstream flooding due to reduced head loss in the upstream improved drainage
system. This approach would need to be validated through modeling analysis (beyond scope
of this plan). If additional flow capacity does result, the ability of the existing downstream
drainage system to convey those flow increases without flooding should also be confirmed.
5-4
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Appendix A
Technical Memoranda
Technical Memorandum 1-2
TECHNICAL MEMORANDUM (1-2) CKWILL
PREPARED FOR: Dan Carey
COPIES TO: Ron Straka
PREPARED BY: Teresa J. Platin
Gerald A. Bibee
DATE: June 13, 1995 (Revised July 13, 1995)
SUBJECT: Consultant Agreement Number CAG-95-038
NE 10th Street/Anacortes Avenue Storm System Improvement
Project: Tasks 1.0 and 2.0.
PROJECT: NPW40801.A0
This memorandum summarizes the findings of Task 1.0, Field Reconnaissance and Drainage
System Inventory and Task 2.0, Hydrologic and Hydraulic Analysis for the subject project.
Task 1.0 involved reconnaissance of the drainage system and the collection of additional data
necessary for the analysis of the existing system and the design of improvements.
For Task 2.0 basin characteristics for the hydrologic anal sis were defined and the sub-basins
Y
contributingrunoff the area's drainage system were modelled in the hydrologic software
g Y
package WaterWorks. The existing drainage system was simulated hydraulically using the
same software package, producing comparative hydraulic capacities of the reaches, hydraulic
profiles and an indication of the extent of flooding under existing conditions.
Task 1.0
Data Review and Assessment
Existing data provided by the City was reviewed. This included system inventory records,
basin delineations, soils data and existing flooding history information. Additional data needs
were then identified, and a survey crew was instructed to perform a field survey of the study
area trunk drainage system.
Drainage System Field Reconnaissance
The trunk drainage system location was verified, then additional areas were identified for the
collection of survey information, with potential solution opportunities in mind.
Field verification of tributary area boundaries was performed to compare existing City
delineations to actual site conditions. Refinements were made as necessary. As seen in the
base map (Figure 1), the 63 acre project area was divided into sub-basins that correspond to
manholes (input nodes) on the trunk line.
1
Drainage System Inventory
The survey crew inventoried the existing trunk drainage system and selected laterals for the
following storm sewer manhole and pipeline data. This data is presented in Table 1 and
Figures 2 and 3.
• invert and rim elevations
• interconnecting pipe sizes
• elevations
• material types
This information was also collected for four catch basins to the south of the project area in the
new development. The possibility of conveying stormwater from Anacortes Court to this area
may be considered in the solutions development process. The corrugated metal pipe arches
(CWAs)that convey stormwater to the culvert beneath Sunset Boulevard were also
inventoried.
Actual inventoried pipe sizes varied from City records for some pipe reaches. The locations,
inventoried diameters and City record diameters are presented in Table 2. Several manholes
and catch basins could not be located during the field survey. It is likely that the following
structures were paved over during roadway improvements:
• 14.C3-11
• 14.C4-4
• 14.D3-1
• 14.D3-2
Instead of finding the storm sewer manhole 14.C44 in the cul-de-sac of Anacortes Court, a
sanitary sewer was found in the location indicated on the City map. A single catch basin was
found on either side of Anacortes Court, as shown in Figure 4. The catch basin on the east
side of the street receives runoff from a private catch basin on the adjacent property. The
road catch basin appears to drain to the west, where it combines with the runoff collected by
the catch basin on the west side of the street. This inlet likely collects street runoff as well as
roof top inputs from the surrounding properties. Stormwater is conveyed to manhole#3 at
the intersection of Anacortes Court and NE 10th Street.
Spot elevations for the top of curb were taken along Anacortes Court, historically the location
of the most severe flooding in the project area. This information is shown in Figure 4. The
top of the curb is the highest elevation along the cul-de-sac. Lawns slope down towards the
houses, and it appears that the street is providing storage up to the elevation of the curb top,
at which point the stormwater runs down the lawns and approaches the houses.
The data review and system inventory findings were used as the basis of the analyses of Task
2.0.
2
Task 2.0
Drainage Basin Delineation and Runoff Characterization
Using existing delineation information from the City and field reconnaissance, the drainage
basins tributary to the main trunk system were delineated. These sub-basins were
planimetered to determine their surface area.
Curve numbers for the percent of pervious and impervious areas based on the King County
Surface Water Design Manual standards were determined using an aerial photograph of the
project site and field reconnaissance data. Typically, several different pervious land cover
types, ranging from gravel lots to dense trees covered each sub-basin. Therefore, it was
necessary to calculate a weighted pervious curve number, indicative of the relative percent
coverage of each land surface type. Impervioius ground was assigned the standard curve
number of 98 for the independent entry of percent impervious.
Times of concentration were calculated using the WaterWorks Tc-calculator, internal to the
hydrologic modelling program. This calculator computes times of concentration for sheet,
shallow channel and channel flow, based on the methods described in the SCS Technical
Release No. 55. Data for the lengths of overland and channelized flow were input along with
the slope of the conveyance surface and the roughness characteristics. Input data for the
hydrologic simulation is presented in Table 3.
Precipitation for the area was determined using the King County Surface Water Design
Manual Isopluvials. The following 24-hour precipitation values were used in the
corresponding storm simulations:
• 2-Year Event: 2.0 inches
• 10-Year Event: 2.9 inches
• 25-Year Event: 3.4 inches
• 100-Year Event: 3.9 inches
Existing Condition Hydrologic Model Simulation
Hydrologic model simulation was performed using the WaterWorks model, a program that
follows the Santa Barbara Unit Hydrograph(SBUH) method to determine sub-basin runoff
contributions for each design storm. The runoff volume, peak runoff and unit discharge for
the four design storms for each sub-basin are tabulated in Table 4.
Flows were combined and routed through the main stormwater trunk reaches as part of the
hydraulic modeling. The cumulative flows from the sub-basins are presented as part of the
following discussion.
3
Existing Condition Hydraulic Model Simulation
The existing stormwater trunk drainage system was simulated using the WaterWorks model.
This portion of the program is based on King County's Surface Water Design methodology
for backwater calculations.
Each structure (manhole/sub-basin node)was detailed in the model using the following survey
data: rim elevations; pipe inverts; and manhole bottom elevations. Coordinates for the
location of each manhole were entered to provide a basis for the calculation of pipe reach
lengths and losses due to friction and bends. The entrance loss coefficient (Ke) was assumed
to be 0.5, for a square edge with headwall entrance type.
Pipe reaches were established by the model, using the structure coordinates and the pipe types
and inverts entered in the structures fields. A network was then established that contained
each of the pipe reaches forming the main trunk line. The upstream end of the network
started with"mhI" (City ID 14.D4-1) on NE Duvall and NE IOth Street and ended at"mh10"
(City ID 9.C8-19) on Whitman Court NE,just south of Sunset Boulevard. The last node in
the system, "mh10" contains the south end of the existing 12-inch siphon pipes. Because the
hydraulic model is not designed to handle siphons, the reach connecting"mh10" to the
southern CMPA was eliminated from the modelled network. To include the effects of this
reach and the siphon, hand calculations were performed to ascertain the tailwater elevation at
the pipe delivering runoff to"mh10." These calculations, a tabulation of friction losses
causing a rise in the hydraulic gradeline above that found at the partially full CMPAs, are
presented in Table 5.
As seen in Table 5, friction losses were calculated and tabulated to determine the hydraulic
gradeline at"mh10." To begin the analysis, the water level in the CMPAs was assumed to be
at the top of the 18" diameter pipe connected to the CMPA. Losses were calculated using the
pipe lengths, changes in elevation and the design flows for each storm event. The following
standard multipliers(King County Surface Water Design Manual for most)were used in the
calculations:
• Friction Loss=Friction Slope * V2/2g
• Entrance Loss=0.3 * V2/2g
• Exit Loss= 1 * V2/2g
• Junction/Bend Loss=0.2 * V2/2g
Table 5 shows friction losses for pipe reaches(denoted as"p#") and entrance, exit and
junction/bend losses at the nodes. The total losses are the summation of each of these
individual values, and represent the rise in the hydraulic grade line between the CMPA
collection point and the connection of Node 10 and Pipe 9 (p9).
The calculated hydraulic grade line elevation was used as the starting condition for the model.
The 2-year storm event generated partially submerged starting conditions, while the 10-, 25-
and 100-year events resulted in full submergence of the pipe delivering runoff to"mh10." The
hydraulic grade line elevation was set at 0.5 feet above the rim elevation for each storm that
caused complete surcharging of"mh10."
4
The results of the hydraulic simulation are summarized in Table 6. The full flow capacities of
each pipe reach are presented, along with the maximum flows for the 4 design storms, to
provide a comparison of the potential flows and the existing capacity of the system.
Simulated flooding events are also recorded in this table. These events were determined by
noting the locations where the model produced headwater elevations above the manhole rim
elevations. As shown in the table, the pipe reaches from"mh2" to"mhY and from"mhY to
"mho" had simulated flooding for all of the design storms. These manholes serve the
Anacortes Court area, a location of historic flooding. The results of hydrograph routing
between"mho" and "mh8" indicated that flooding could be expected during the 10-, 25- and
100-year design storms in the area served by this section of the network. A summary of the
maximum flows and the headwater elevations generated for each reach of the network is
presented in Table 7.
City of Renton Memorandums dated September 5, 1991 and October 14, 1994 address the
flooding at Anacortes Court NE and between this street and Anacortes Avenue NE on NE
10th Street. The frequency of the flooding is not estimated in these reports, however based
on the model results, it is likely that 2-year events and perhaps smaller will cause inundation of
this area. It should be noted that Anacortes Court effectively stores stormwater runoff, thus
lowering the peak amount of flow moving through the drainage system. The storage of
stormwater in localized depressions and the dissipation of stormwater across relatively flat
areas is not accounted for in this simulation model. Therefore, it is likely that the model has
slightly overestimated the hydraulic gradelines downstream of Anacortes Court.
Comparison of Existing Condition Hydrologic and Hydraulic Simulation
Results to Actual Flooding Data
The findings of Tasks 1.0 and 2.0 support the City's flooding reports and conclusion that
several reaches of pipe in the project area are undersized. Subsequent tasks will address
possible means of reducing flooding, either by better conveyance or the use of a stormwater
storage facility.
c:ateresaVmc«,\n�i 2.dm 5
Table 1
Storm Drain System Inventory
NE loth Street /Anacortes Court Stormwater Drainage Improvements
_ OF HYDRAULIC
INVERT
RE TN ON ID FIELD ID ANALYSIS ELEVATION ELEVATION DESCRIPTION
NODE ID
938-13 SDMH#1 394.73' 387.96' 36" i , cl inv.
9.C8-21 SDMH#2 394.85' 385.08' cl bottom w/sediment
389.20' 24"pipe,North inv.
9.C8-19 SDMH#3 mh10 395.08' 385.78' cl bottom
389.27' 24"pipe, South inv.
9.C8-18 SDMH#4 mh9 395.58' 389.58' cl bottom
390.05' 24"pipe,North inv.
390.35' 12"pipe, SE inv.
390.05' 18"pipe, South inv.
390.53' 18"pipe,NW inv.
14.C2-4 SDMH#5 mh8 399.82' 394.78' 18"pipe,cl inv.
395.36' 6"pipe, W inv.
14.C2-3 SDCB#6 398.99' 395.49' cl bottom
396,27' 6"pipe,W inv.
396.25' 6"pipe,E inv.
14.C2-7 SDMH#7 mh7 404.81' 398.38' cl bottom
398.92' 18" i S inv.
398.74' 18"pipe,N inv.
399.62' 6"pipe, SW inv.
14.C2-6 SDCB#8 406.27' 404.06' cl bottom
14.0-11 SDMH#9 Paved over
14.0-6 SDCB#10 408.31' 403.22' cl bottom
404.75' 6"pipe,W inv.
404.58' 6"pipe,NE inv.
14.0-12 SDMH#11 413.91' 409.30' cl bottom
410.77' 12"pipe, SW inv.
410.72' 12"pipe,E.inv.
Note: Elevations determined using City BM#159, 1988 NAVD as reference
1
CITY OF HYDRAULIC
ERT
RENTON ID FIELD ID ANALYSIS ELEVATION ELEVATION DESCRIPTION
NODE ID
14.0-10 SDMH#12 mh6 411.92' 400.84' cl bottom
401.62' 18"11!pS,N inv.
401.83' 18"pipe, S inv.
408.26' 12"pipe, W inv.
408.76' 12"pipe,E inv.
14.0-13 SDME#13 413.72' 408.87' cl bottom
410.25' 12"pipe,W inv.
14.0-3 SDMH#14 414.97' 407.77' cl bottom
409.51' 12"pipe,W inv.
409.39' 12"pipe,E inv.
14.0-9 SDMH#15 414.54' 402.65' cl bottom
402.75' 18"pipe,N inv.
402.90' 18"pipe, S inv.
14.04 SDMH#16 mh5 413.58' 402.32' cl bottom
403.45' 18"pipe,N inv.
403.52' 18"pipe,E inv.
407.29' 12"pipe, W inv.
14.0-2 SDMH#17 mh4 412.23' 403.59' cl bottom
404.40' 18"pipe, W inv.
404.66' 18"pipe,E inv.
404.89' 18"pipe, S inv.
14.0-1 SDCB#18 409.29' 405.21' cl bottom
406.14' 18"pipe, W inv.
406.15' 12"pipe,NE inv.
Not on City Map SDMH#19 409.80' 405.05' cl bottom
(Anacortes Ave NE) 406.41' 12"pipe, SW inv.
406.41' 12"pipe,N inv.
14.C4-3 SDMH#20 415.73' 409.66' cl bottom
411.14' 12"pipe,E inv.
411.00' 12"pipe, W inv.
Not on City Map SDCB#21 413.08' 408.69' cl bottom
(NE loth Street) 410.06' 12"pipe, W inv.
410.01' 12"pipe, S inv.
410.06' 12"pipe,E inv.
Note: Elevations determined using City BM#159, 1988 NAVD as reference
2
CITY OF HYDRAULIC
INVERT
RENTON ID FIELD ID ANALYSIS ELEVATION ELEVATION DESCRIPTION
NODE ID
14.C4-2 SDMH#22 mh3 409.88' 405.22' cl bottom
406.56' 18"pipe,N inv.
406.43' 12"pipe, W inv.
406.58' 12"pipe,E inv.
406.88' 10"pipe, S inv.
Not on City Map SDCB#23 409.13' 406.54' cl bottom
(Anacortes Ct. NE) 407.33' 8"pipe, N inv.
407.31' 6"pipe,E inv.
407.37' 6"pipe, W inv.
In Anacortes Ct. SDCB#24 409.20' 407.21' cl bottom
(Anacortes Ct.NE) 407.52' 6"pipe, W inv.
407.53' 6"pipe,E inv.
House#968 Drain SDCB#25 409.00' 408.28 cl bottom
408.38 4"pipe, W inv.
408.33 4"pipe,E inv.
14.C4-1 SDCB#26 410.74' 406.35' cl bottom
407.86' 12"pipe, W inv.
407.99' 12"pipe,E inv.
14.1)4-3 SDMH#27 mh2 412.47' 408.28' cl bottom
408.78' 12"pipe,W inv.
408.84' 12"pipe,E inv.
Not on City Map SDCB#28 414.22' 409.30' cl bottom w/sediment
(NE loth Street) 409.65' 12"pipe, W inv.
409.65' 12" pipe,E inv.
409.87' 12" pipe, S inv.
14.D4-2 SDMH#29 416.46' 409.75' cl bottom w/sediment
410.22' 12"pipe,W inv.
410.24' 12'pipe,E inv.
Not on City Map SDMH#30 433.02' 415.5 P cl bottom
(NE 10th Street) 415.70' 12"pipe,E inv.
415.72' 12"pipe, W inv.
Note: Elevations determined using City BM#159, 1988 NAVD as reference
3
HYDRAULIC
VERT
RCITY
TN ON ID FIELD ID ANALYSIS ELEVATION ELEVATION DESCRIPTION
NODE ID
14.D4-1 SDMH#31 mhl 437.82' 425.37' cl bottom
426.11' 12"pipe,W inv.
426,19' 12" pipe,E inv.
433.34' 12"pipe,NW inv.
I4.E4-11 SDMB#32 453.08' 436.00' cl bottom
436.54' 12"pipe,W inv.
436.61' 12"pipe,E inv.
14.133-2 SDM14#33 Paved over
14.133-1 SDMB#34 Paved over
New Cul-de-Sac SDCB#35 411.56' 408.11' cl bottom
(Mission Hills) 409.56' 12"pipe, S inv.
New Cul-de-Sac SDCB#36 411.47' 407.87' cl bottom
(Mission Hills) 409.07' 12"pipe, W inv.
409.07' 12"pipe,N inv.
409.07' 12'pipe,E inv.
New Cul-de-Sac SDCB#37 412.62' 408.87' cl bottom
(Mission Hills) 410.12' 12"pipe,N inv.
410.02' 12"pipe,E inv.
New Cul-de-Sac SDCB#38 412.78' 409.18' cl bottom
(Mission Hills) 410.48' 12"pipe, S inv.
9.C8-20A 388.48' 54" culvert inlet
9.C8-20B 388.51' 54"culvert inlet
396.14' Top of culvert headwall
Culvert on north side of Sunset Blvd.
386.32' 30" culvert outlet
386.29' 54" culvert outlet
386.32' 54"culvert outlet
Culvert on east side of Union Ave.
385.30' 30" culvert inlet
385.08' 54"culvert inlet
Culvert on west side of Union Ave. 383.20' 30"culvert outlet
383.89' 54" culvert outlet
Note: Elevations determined using City BM#159, 1988 NAVD as reference
1002B1 F9.XLSSheetl 4
Table 2
Trunk Line System Inventory: Comparison to City Records of Pipe Diameters
NE loth Street/Anacortes Court Stormwater Drainage Improvement Project
Inventoried Diameter City Records Diameter
Reach ID Ci ID (in.) (in.)*
mhl-2 14.D4-1 to 14.D4-3 12 12
mh2-3 14.D4-3 to 14.C4-2 12 12
mh3-4 14.C4-2 to 14.0-2 18 12
mh4-5 14.0-2 to 14.C3-4 18 15
mh5-6 14.C3-4 to 14.0-10 18 18
mh6-7 14.0-10 to 14.C2-7 18 15
mh7-8 14.C2-7 to 14.C2-4 18 15
mh8-9 14.C2-4 to 9.C8-18 18 15
mh9-10 9.C8-18 to 9.C8-19 24 18
siphon 9C8-19 to 9.C8-21 12(2) rda
*From City of Renton Attributes: Manhole/Catch Basin and Pipe Inventory,date unknown.
HYDROL02.XLS Pipe Sizes
Table 3
Hydrologic Analysis Basin Characteristics - Existing Conditions
NE loth Street/Anacortes Court Stormwater Drainage Improvement Project
WaterWorks BASIN input Data
SUB- PERCENT PERCENT PERVIOUS TIME OF
BASIN AREA(ac) IMPERVIOUS PERVIOUS CN * CONCENTRA-
TION ** min
0 0.38 20% 80% 81.00 68.07
1 2.39 80% 20% 86.00 23.38
2 4.36 90% 10% 89.00 14.37
3 2.54 80% 20% 87.00 15.76
4 2.19 85% 15% 86.30 14.03
5 2.38 90% 10% 87.00 4.81
6 6.13 42% 58% 86.00 21.03
7 4.00 42% 58% 86.00 24.87
8 3.98 42% 58% 86.00 24.12
9 1.46 42% 58% 86.00 19.46
10 6.48 42% 58% 86.00 25.88
12 12.78 15% 85% 84.20 41.2
13 8.15 38% 62% 86.00 16.93
14 1.16 46% 54% 86.00 17.07
15 4.96 28% 72% 86.60 36.09
NOTES:
*Pervious Curve Number(CN)is a weighted average based on the various pervious
land covers in each sub-basin. Impervious CN in all cases is 98.
** Time of concentration is defined for flow in the sub-basin to the collection node.
HYDR01-02ALS[Input] 1
Table 4
Hydrologic Analysis Results-Existing Conditions
NE 10th Street/Anacortes Court Stormwater Drainage Improvement Project
WaterWorks Hydrologic Modelling Results
11 2-Y 24-HOUR EVENT 10-YEA 24-HOUR EVENT 25 YEA 24-HOUR EVENT 100-YEA 24-HOUR EVENT
SUB- AREA RUNOFF PEAK UNIT RUNOFF PEAK UNIT RUNOFF PEAK UNIT RUNOFF PEAK UNIT
BASIN (ac) VOLUME RUNOFF DISCHARGE VOLUME RUNOFF DISCHARGE VOLUME RUNOFF DISCHARGE VOLUME RUNOFF DISCHARGE
ac-ft cfs cih/ac ac-R cfs cfs/ac ac-R cfs cfs/ac ac-tt) (cfs) (cfs/ac
0 0.38 0.02 0.04 0.10 0.05 0.08 0.22 0.06 0.11 0.29 0.07 0.14 0.37
1 2.39 0.30 0.95 0.40 0.48 1.49 0.62 0.57 1.78 0.75 0.67 2.08 0.87
2 4.36 0.61 2.14 0.49 0.93 3.24 0.74 1.11 3.84 0.88 1.29 4.45 1.02
3 2.54 0.33 1.11 0.44 0.51 1.73 0.68 0.61 2.07 0.82 0.72 2.42 0.95
4 2.19 0.29 1.03 0.47 0.45 1.60 0.73 0.54 1.91 0.87 0.63 2.22 1.01
5 2.38 0.33 1.39 0.58 0.50 2.11 0.89 0.60 2.51 1.05 0.70 2.90 1.22
6 6.13 0.59 1.79 0.29 1.00 3.16 0.52 1.24 3.93 0.64 1.48 4.71 0.77
7 4.00 0.39 1.13 0.28 0.66 1.99 0.50 0.81 2.49 0.62 0.97 2.98 0.75
8 3.98 0.38 1.13 0.28 0.65 2.00 0.50 0.81 2.49 0.63 0.96 2.99 0.75
9 1.46 0.14 0.43 0.29 0.24 0.75 0.52 0.30 0.94 0.64 0.35 1.12 0.77
10 6.48 0.62 1.79 0.28 1.06 3.17 0.49 1.31 3.95 0.61 1.57 4.74 0.73
12 12.78 0.91 1.93 0.15 1.69 3.95 0.31 2.15 5.17 0.40 2.62 6.42 0.50
13 8.15 0.76 2.30 0.28 1.31 4.16 0.51 1.62 5.22 0.64 1.94 6.29 0.77
14 1.16 0.11 0.35 0.30 0.19 0.19 0.17 0.24 0.77 0.66 0.28 0.92 0.80
15 4.96 0.44 1.07 0.22 0.77 1.96 0.39 0.96 2.47 0.50 1.15 2.98 0.60
NOTE: Data Is provided for each Individual sub-basin,cumulative results are not tallied here.
HYDROL02ALS tResuftsj 1
Table 5
NE 10th Street/Anacortes Court Stormwater Drainage Improvement Project
Head Losses for North End of System: Node 9.C8-19 to Connection with CMPA
Friction Loss Coefficients for Pipes
Pipe ID 9�(ft) Q2(cfs) Sf2 Sf2 x L Q10(cfs) Sf10 Sf10 x L Q25(cfs) Sf25 St26 x L
11 97 16.7 0.0046 OA506 28.9 0.0139 113492 35.8 0.0213 a_2.0703 a
10 30 16.7 0.0046 0.1393' 28.9 0.0139 0.4173 35.8 0.0213 0.6403
Pipe ID Pipe Q100 Length(ft) (cfs) Sf100 SHOO x L
11 97 42.8 0.0305 2.9591
10 30 42.8 0.0305 0.9162'''
riction Loss for Nodes and Pipes: 2-Year Event 11
Pipe Friction Entrance Exit Loss Jn/Bend Total L
ID Diameter Q(cfs) V(fps) V"212g(ft) Loss(ft) Loss(ft) (ft) Loss(ft) (ft)
ft
PA 2 16.7 5.32 0.44 0.44 0.09 0.53
p11 2 16.7 5.32 0.44 0.20 0.20
Node 11 1 8 10.19 1.61 0.48 1.61 0.32 2.42
p10(2-12 1 8 10.19 1.61 022 022
Node 10 2 16 5.09 0.40 0.12 0.40 0.08 0.60
Loss between CMPA&p9= 3.97
Friction Loss for Nodes and Pipes: 10-Year Event
If
Friction Entrance Exit Loss Jn/Bend Total L
Q(cfs) V(fps) V"2/2fl(ft)
Loss(ft) Loss(ft) (ft) Loss(ft) (ft)
28.9 920 1.31 1.31 026 1.58
28.9 920 1.31 1.77 1.77
14.5 18.46 5.29 1.59 5.29 1.06 7.9414.5 18.46 529 2.21 221
28 8.91 123 0.37 1.23 0.25 1.85
Loss between CMPA 8 p9= 15.35
Friction Loss for Nodes and Pipes- 25-Year Event
Pipe Friction Entrance Exit Loss Jn/Bend Total Loss
ID Diameter Q(cfs) V(fps) V"2/2g(1t) Lou(ft) Loss(ft) (ft) Loss(it) (ft)
PA 2 35.8 11.40 2.02 2.02 0.40 2.42
p11 2 35.8 11.40 2.02 4.17 4.17
Nods 11 1 17.5 22.28 7.71 2.31 7.71 1.54 11.56
p10(2-12 1 17.5 2228 7.71 4.94 4.94
Node 10 2 35 11.14 1.93 0.58 1.93 0.39 2.89
Loss between CMPA&e9
Friction Loss for Nodes and Pipes: 100-Year Event
Pi
pe Friction Entrance Exit Loss Jn/Bend Total Loss
ID Diameter Q(cis) V(fps) V"2/2g(ft) Lou(ft) Loss(ft) (ft) Loss(ft) (ft)
CMPA 2 42.8 13.62 2.88 2.88 0.58 3.46
p11 2 42.8 13.62 2.88 8.53 8.53
Node 11 1 21 26.74 11.10 3.33 11.10 222 16.65
p10(2-12 1 21 26.74 11.10 10.16 10.16
Node 10 2 42 13.37 2.78 0.83 2.78 0.56 4.16
Loss between MPA I p =
NOTE:
Tailwater level exceeds catch basin rim. Water level set at maximum elevation of rim elevation+0.5.
An explanation of the calculations used in this spreadsheet can be found on the following page.
rnDRAULixLS IFrkt Lwsi
Definition of Calculations for Table 5: NE 10th Street/Anacortes Court
Stormwater Drainage Improvement Project Head Losses
for North End of System: Node 9.C8-19 to Connection with CMPA
Friction Loss Coefficients for Pipes
Pipe Id=pipe identification. u/s manhole=identifier(i.e. for pipe starting at mh10 and ending at mh11, pipe is p10)
Pipe Length (ft)=from City data
02(cfs)=flow rate determined by WaterWorks modelling run
Sf=((Q*n)/(K"dA2.67))^2 from the Handbook of Hydraulics by Brater and King
n=0.012, D/d=1.0, therefore K'=0.463
Sf x L=Sf x pipe length
Friction Loss for Nodes and Pipes
Pipe Diameter(ft)=Existing diameter, determined during field survey
Q(cfs)=flow rate determined by WaterWorks modelling run. Note that flow is divided through the 2-pipe siphon system
V(fps)=Q/A(assumes that pipes are flowing full-ok for this approximation)
VA2/2g (ft)=velocity head
Friction Loss(ft)=("Sf x L"from Friction Loss Coefficients calculation)x(VA2/2g)
Entrance Loss(ft)=(0.3)x(V^2/2g)
Exit Loss(ft)=(1.0)x(VA2/2g)
Jn/Bend Loss(ft)=(0.2)x(VA22g)
Total Loss(ft)=E(Friction Loss+ Entrance Loss+ Exit Loss+Jn/Bend Loss)
Loss Between CMPA&p9=E(Total Loss)
HYDRAUL2XLS Sample Ca{cs 1
Table 6
WaterWorks Hydraulic Analysis Results - Existing Conditions
NE loth Street /Anacortes Court Stormwater Drainage Improvement Project
TRUNK 2-YEAR 10-YEAR 25-YEAR 100-YEAR
DRAINAGE
ELEMENT FLOW EVENT EVENT EVENT EVENT FLOODING CONSIDER FOR
SIZE AND MAXIMUM MAXIMUM MAXIMUM MAXIMUM EVENTS REPLACEMENT
REACH(BY TYPE CAPACITY* FLOW ** FLOW ** FLOW** FLOW ** *** T(yes/no)
NODE (cfs)NUMBER) (cfs) (cfs) (cfs) (cfs)
9 to 10 24"conc. 28.37 17.06 29.55 36.67 43.85 yes
8 to 9 18"conc. 15.48 16.11 28.06 34.89 41.78 yes
7 to 8 18"conc. 20.80 13.26 23.73 29.74 35.81 ALL yes
6 to 7 18"conc. 11.80 11.69 21.32 26.88 32.50 10,25,100yr yes
5 to 6 18"conc. 6.44 8.77 16.18 20.46 24.81 10,2 5,1 00yr yes
4 to 5 18"conc. 6.64 7.21 13.42 17.03 20.70 10,25,100yr yes
3 to 4 18"conc. 8.44 5.42 10.26 13.08 15.95 ALL yes
2 to 3 12"conc. 2.32 3.00 5.91 7.63 9.40 ALL yes
1 to 2 12"conc. 2.65 1.93 3.95 5.17 6.42 no
NOTES
*Full Flow Capacity based on Mannings Equation for normal flow.
** Event Maximum Flows are cumulative. They do not take into account flow dispersal or localized storage.
*** Flooding Events are for storm frequencies that caused manhole overtopping(greater than 0.5')during computer simulation.
With improved delivery to reaches "8 to 9"and "9 to 10,"flooding can be expected;therefore, replacement is suggested.
HYDRAUL2.XLS[Output) t
Table 7
WaterWorks Hydraulic Analysis Headwater Elevations
NF, 10th Street/Anacortes Court Stormwater Drainage Improvement Project
TRUNK 10-YEAR 25-YEAR 100-YEAR
2-YEAR EVENT
DRAINAGE STRUCTURE HYDRAULIC EVENT EVENT EVENT
SYSTEM RIM GRADE LINE HYDRAULIC HYDRAULIC HYDRAULIC
REACH(BY ELEVATION ELEVATION GRADE LINE GRADE LINE GRADE LINE
NODE (ft) (ft) ELEVATION ELEVATION ELEVATION
10 395.08 393.95 395.58 395.58 395.58
9 to 10 395.58 393.73 394.67 394.45 393.93
...................
........ ..
8 to 9 399.82 ..........
.................. . ... ....... .. . ...
................... ..... ...........
............
7 to 8 404.81 402.19
..............
A
94
54
4
. ............. ............. ...... .......
..........
6 to 7 411.92 405.49 .........
12. .....I
.. . ..... :,` .. .. ......- ..........
..........
13
OM.............
..............
5 to 6 413.58 408.62 ......... .........41.
4.........
4 to 5 412.23 410.13 . ....
....... ........ .. ... ..
... .......................
I..."...... ....... . .....
. . ..........
.. . ....... ------.. ...V
3 to 4 409.88
....... ....... .......4 7
41. Z
2 to 3 412.47
1 to 2 437.82 426.41 427.77 428.49 430.34
Legend
Hydraulic grade line elevation is above the structure rim elevation.
The program sets the HGL at the structure at 0.1 feet above the rim
to allow for ponding or bypass.
HYDRAMALS[HGLI
FIGURE-5 / SIZE
TABLE
TITLE
PRESENT LOCATION AND STATUS:
GENERAL DESCRIPTION AND IDENTIFYING CHARACTER:
PRINT OUTSIDE INSIDE
Technical Memorandum 3-2
TECHNICAL MEMORANDUM (TM 3-2) CWHILL-
PREPARED FOR: Dan Carey
COPIES TO: Ron Straka
PREPARED BY: Teresa J. Platin
Gerald A. Bibee
DATE: June 29, 1995 (Revised August 1995)
SUBJECT: Consultant Agreement Number CAG-95-038
NE 10th Street/Anacortes Avenue Storm System Improvement
Project: Subtask 3.1 - Conceptual Solutions Development/Screening
PROJECT: 116868.A0.3 0
This memorandum summarizes the results of Sub-Task 3.1, Conceptual Solutions
Development and Screening for the subject project. It presents the alternative improvements
considered, their feasibility, benefits, potential impacts and comparative construction cost
estimates. This memorandum is intended to provide the basis for screening the alternatives
with the City to two options for further consideration.
The hydrologic and hydraulic modelling results of Task 2.0 showed that most of the existing
drainage system in the Honey Dew Estates Development is inadequately sized to convey peak
stormwater flows from events larger than the 2-year design storm. Portions of the system
(e.g.,NE loth Street near Anacortes Court) have deficient capacity to convey estimated 2-
year event peak flows. Several conceptual solutions (alternatives)were developed to address
this situation, based on discussion with City staff. Those alternatives are discussed below.
For this initial screening process, the level of analysis detail employed was limited. Therefore,
improvement needs should be considered as preliminary and subject to further refinement.
Order-of-magnitude cost estimates were developed for comparison of alternatives. Actual
implementation costs may vary from the preliminary construction cost estimate ranges.
Alternative Improvement Concepts
The alternatives considered fall within three categories, as follows:
• Alternative 1—Conveyance
— IA: Trunk Storm Drain System Replacement
— 113: Anacortes Avenue NE Bypass with Trunk Storm Drain Reach
Replacements
1
• Alternative 2—Sub-Surface Detention Storage
— 2A: Whitman Court and NE 1 lth Street
— 2B: NE IOth Place
— 2C: Anacortes Court NE and NE 10 Street
• Alternative 3—Diversion
— 3A: NE loth Street/North to Existing Creek and Arches
— 3B: NE loth Street/West to Union Avenue NE
— 3C: NE loth Street to Mission Hills Development (with Sub-Surface Storage)
Criteria and Assumptions
Conveyance
The King County Surface Water Design Manual (the design manual), as partially adopted by
the City, specifies that"pipe systems shall be designed to convey and contain at least the peak
runoff rate for the 25-year design storm..." The 100-year storm was selected for preliminary
pipe sizing to maintain compliance with the design manual's requirement that surcharged pipe
systems convey the 100-year runoff without flooding buildings or overtopping roadway
crowns. In only a few cases did the more conservative flow values cause an increase in pipe
sizes above those required for the 25-year event peak flows.
Uniform full-flow capacity was used to determine the pipe diameters required to convey the
peak design storm discharge(as computed in the hydrologic modelling of Task 2.0), unless
the pipe reach capacity was controlled at the inlet. For those inlet control conditions, the
"Inlet Control Nomograph"from the Bureau of Public Roads was used to size pipes.
Surcharge in the manholes was limited to within 0.5 feet of the rim elevation.
Storage
The minimum storage requirement specified in the design manual is that necessary to control
the peak flow from the 10-year, 24-hour design storm to existing condition peak flow release
rates. Downstream impacts from the 100-year flow also need to be considered.
Costs
Order-of-magnitude construction cost estimates for pipe replacements were based on
estimated unit prices of all new pipes (installed), the addition of new manhole and control
structures and resurfacing. The lower reaches of the existing storm drain are centered
between the sanitary sewer and water lines in a 15-foot corridor. Removal and replacement of
2
the storm drain within this corridor will require trench shoring measures. The cost estimates
assume the use of a trench box, but sheeting and shoring may be necessary in some reaches,
thereby raising the costs. The replacement/addition of structures to accommodate the larger
replacement pipes was considered in the cost estimates, with a general guideline applied to the
sizing of manholes. The manhole diameter was assumed equal to 2 feet plus the largest pipe
diameter at the structure. Another foot was added to manholes at bends in the system to
account for geometric constraints. Manhole depths were assumed to fall within the range of 6
to 12 feet.
Order-of-magnitude cost estimates for the storage options were developed using a rough
approximation(based on previous projects) of$300,000 per acre-foot of underground storage
volume required.
Contingency(30%), mobilization and general conditions (10%), undefined costs (10%) and
sales tax (8.2%)were applied to all estimated project costs; however, engineering/
administration and easement acquisition costs were not included.
Alternative Improvements Description and Evaluation
Alternative 1—Conveyance
Results of the modelling (reference June 13, 1995 Task 1.0/2.0 memorandum) show that the
trunk line leading to the corrugated metal pipe arches (CMPAs) near Sunset Boulevard is
inadequately sized to convey the 25-year design storm peak runoff. Alternative 1 would
replace deficient trunk storm drain reaches. Conveyance improvements would only provide
system-wide flooding relief if implemented as an entire improvement project. However, if
phasing is required due to funding constraints, it is recommended that all conveyance
alternatives proceed from the downstream end of the system to the upstream end.
Alternative lA—Trunk Storm Drain System Replacement
Description
As shown in Figure IA and Table 1, Alternative IA includes the replacement of the entire
trunk system with pipes sized for the 100-year design storm. A concrete junction structure to
connect the improved system to both 58"x 36" CMPAs would be installed to split the flow
between the two arch pipes. All existing manholes along the main trunk line(except mhl, mh2
and the catch basin between them)would be upgraded to accommodate the larger diameter
replacement pipes.
3
Table 1
Alternative IA Conve ance Improve ents
Average
100-Year Existing Replacement Depth to Length
Pipe Design Flow Diameter Diameter Invert of Reach
Reach cfs in in Elev. (ft) (ft
mh 1-2 6.4 12 18 10 590
mh2-3 9.4 12 24 4 455
mh3-4 16.0 18 24 7.5 310
mh4-5 20.7 18 30 12 260
mh5-6 24.8 18 30 13.5 410
mh6-7 32.5 18 30* 11.5 260
mh7-8 35.8 18 30* 8.5 115
mh8-9 41.8 18 36* 8.5 170
mh9-10 43.8 24 36* 10 60
siphon approx. 44 12 2 pipes) 36* 6 30
to arch approx. 45 24 36* 6 85
*When denoted by an asterisk, the replacement diameter was determined using the
Inlet Control Nomo ra h, otherwise, it was calculated using Mannin s Equation.
Feasibility
The replacement of existing pipes with larger pipes on the same slope is technically feasible;
however, some adjustments in depth will be required to provide adequate cover in various
improvement reaches. The CMPAs downstream of the system also presently receive flows
from outside of the project sub-basin boundaries. The cumulative impact of those flows
combined with study area flows should be considered in an evaluation of the downstream
impacts of this alternative (beyond this scope of work). The existing storm drain lies between
the sanitary sewer and water main in an approximately 15-foot wide corridor, and sections of
the upstream pipes extend within easements across private properties. These construction
issues will affect project implementation requirements and costs.
Bene,rhs/Potential Impacts
Implementation of this alternative would provide a significant increase in the level-of-
protection from flooding. The upgraded system was sized to convey flows from the 100-year
storm to the downstream CMPAs.
Improvements to the existing system could potentially impact the downstream system through
the delivery of higher peak flows (on the order of three times the amount that would presently
reach the CMPAs in a 100-year event). Peak storm flows are presently being dispersed by
upstream flooding, ponding and runoff to other basins, while an improved system would
convey this runoff at a higher peak rate directly to the CMPAs. Construction impacts to
roads, utilities and some private property in the Honey Dew Estates Development would also
occur with the implementation of this alternative.
4
Estimated Cost
Cost items for Alternative I include the pipe upgrades listed in Table IA, eight 60-inch
diameter manholes, two 72-inch diameter manholes and the junction structure at the CMPAs.
The preliminary estimate of the order-of-magnitude construction cost for this alternative is
approximately $510,000.
Alternative 1B—Anacortes Avenue NE Bypass with Trunk Storm Drain
Reach Replacements
Description
Previous reports of flooding in this basin and modelling results show that flooding can be
expected most frequently in the area of Anacortes Court NE and NE 1 Oth Street. Alternative
1B proposes to reduce the peak flow delivered to the pipes between manholes 3 through 6
(see Figure 1B), reducing backwater conditions and associated flooding. This alternative
would consist of a bypass pipeline to convey runoff through a storm drain aligned beneath
Anacortes Avenue NE and 1 lth Street. This would still require some existing-system
upgrades upstream of the bypass, and a complete replacement downstream of the junction
point (manhole 6). Although the existing system and the bypass would initially operate in
parallel, the bypass was sized to convey all of the peak flow through that reach. The
preliminary sizing of the bypass pipe was based on the 100-year design storm peak flow
through this reach, assuming that the existing reach between manholes 3 and 6 could be
plugged and reconnected in the future.
Another bypass option was suggested by the City Staff. This would convey flow through two
separate bypass lines east and west of Anacortes Court NE along NE 1 Oth Place and back into
the main trunk line at manholes 4 and 5 respectively. This option was not considered further
because it was determined that it would not be cost-effective for the small benefit provided, as
only a short reach of the system was being bypassed. This option would require
approximately 1000 feet of 24-foot diameter storm drain, diversion structures and manholes.
Alternative 1B includes the installation of new pipe reaches and structures as detailed in
Table 2.
5
Table 2
Alternative 1B Conveyanee Im rovements
Average
100-Year Existing Replacement Depth to Length
Design Flow Diameter Diameter Invert of Reach
Pipe Reach cfs in in Elev. ft ft
BYPASS
SYSTEM
mh2-A 9.4 24 6 220
mhA-B 16.0 24 6.5 270
mhB-C 20.7 30 9 400
mhC-6 23.7 30 10 495
mh3-A 7.2 24 6 235
EXISTING
UPGRADE
mhl-2 6.4 12 18 10 590
mh5-6 4.1 18 no change n/a 410
mh6-7 30.8 18 30* 11.5 260
mh7-8 34.6 18 30* 8.5 115
mh8-9 40.7 18 36* 8.5 170
mh9-10 42.8 24 36* 10 60
siphon approx. 44 12 2 pipes) 36* 6 30
to arch approx. 45 24 36* 6 85
*When denoted by an asterisk, the replacement diameter was determined using the
Inlet Control Nomo a h, otherwise, it was calculated using Mannin s Equation.
Feasibility
Based on available plans, the bypass line can be constructed along Anacortes Avenue NE
without disrupting existing sanitary or water pipes. No significant issues that would limit
technical feasibility are known to exist. As with Alternative I A, downstream flow impacts
and development area construction impacts could affect project improvement requirements
and costs.
BeneJits✓Potential Impacts
Implementation of this alternative would provide a significant increase in the level-of-
protection from flooding. The upgraded system and new bypass were sized to convey flows
from the 100-year storm to the downstream CMPAs.
The potential impacts of this alternative are the same as those for Alternative IA, with the
exception of the impacts to private property.
6
Estimated Cost
Cost items for Alternative 1B include the bypass pipe reaches and pipe upgrades listed in
Table IA, nine 60-inch diameter manholes, two 72-inch diameter manholes and the junction
structure at the CMPAs. The preliminary estimate of the order-of-magnitude construction
cost for this alternative is approximately $560,000.
Alternative 2-Storage
Alternative 2 proposes to maintain the existing inadequately sized trunk line, and alleviate
some of the peak flow through the system using sub-surface detention facilities (see Figure 2).
Replacement of the existing siphon is recommended with this alternative, as the siphons are no
longer necessary, and they seriously impede flow to the CMPAs. Three different locations
were considered for storage, as described below. Surface detention was considered, but
deemed infeasible based on siting constraints. Preliminary results show that none of the
storage alternatives would alleviate the flooding of 10-year recurrence interval and greater
storm events. Evaluation of the system upstream of proposed storage locations would be
required with this alternative.
Alternative 2A—Whitman Court and NE 11th Street
Description
Alternative 2A would include the construction of a sub-surface storage facility north of the
intersection of Whitman Court and NE 1 lth Street. The 10-year design storm peak flow is
approximately 24 cfs through this area. The hydrograph for mh7 was used to determine the
runoff volume that would need to be detained in temporary storage. Reducing the peak flow
to downstream system capacities would require routing all flows above 5.8 cfs to storage, or
in the case of this particular flow pattern, storing 1.7 acre-feet, with controlled release back to
the trunk drainage system. The hydrographs used in the analysis of this alternative and the
following two alternatives are provided at the end of this memorandum.
Feasibility
The feasibility of Alternative 2A is limited by facility requirements and the practicality of
providing large volumes of subsurface storage within the road right-of-way. System hydraulic
grades compared to road grades and the high construction costs of sub-surface storage raise
feasibility concerns.
Benefits✓Potential Impacts
A preliminary check of the improvement benefits shows that this would provide only a limited
increase in the level of protection throughout the system. Surcharging of the manholes will
still occur at the current problem locations during events between the 2- and 10-year
recurrence interval and beyond.
7
Estimated Cost
This alternative would result in a sub-surface storage facility cost (order-of-magnitude) of
approximately $830,000.
Alternative 2B—NE loth Place
Description
Alternative 2B proposes the construction of a storage facility beneath NE 10th Place. The 10-
year design storm peak flow in the pipe beneath NE 1 Oth Place, near the northern cul-de-sac
of Anacortes Court NE is approximately 16 cfs. Attenuating the hydrograph peak of manhole
5 would require routing all flows above 4 cfs to storage, or in the case of this particular flow
pattern, storing 1.1 acre-feet, with controlled release back to the trunk drainage system.
Feasibility
The feasibility of Alternative 2B is limited by facility requirements and the practicality of
providing large volumes of subsurface storage within the road right-of-way. System hydraulic
grades compared to road grades and the high construction costs of sub-surface storage raise
feasibility concerns.
Benefits/Potential Impacts
A preliminary check of the improvement benefits shows that this storage facility would not
substantially improve the level of protection throughout the system for flows beyond the 2-
year design, due to the extent of contributing drainage area downstream of this location.
Surcharging of the manholes will still occur at the current problem locations for larger storm
events.
Estimated Cost
This alternative would result in a sub-surface storage facility cost (order-of-magnitude) of
approximately $540,000 .
Alternative 2C Anacortes Court NE and NE 10 Street
Description
Alternative 2C includes the construction of a subsurface storage facility east of Anacortes
Court NE. The 10-year design storm peak flow at the intersection of Anacortes Court NE
and NE 10th Street is approximately 10 cfs. Attenuating the hydrograph peak of manhole 3
would require routing all flows above 2.8 cfs to storage, or in the case of this particular
hydrograph, storing approximately 0.77 acre-feet, with controlled release back to the trunk
drainage system.
8
Feasibility
The feasibility of Alternative 2C is limited by facility requirements and the practicality of
providing large volumes of subsurface storage within the road right-of-way. System hydraulic
grades compared to road grades and the high construction costs of sub-surface storage raise
feasibility concerns.
Benefits/Potential Impacts
A preliminary check of the improvement benefits of this alternative shows that it will not
substantially improve the level of protection throughout the system for flows beyond the 2-
year design, due to the extent of contributing drainage area downstream of this location.
Surcharging of the manholes will still occur at the current problem locations during larger
storm events.
Estimated Cost
This alternative would result in a sub-surface storage facility cost (order-of-magnitude) of
approximately $350,000.
Alternative 3 - Diversion
Diversion of stormwater runoff to reduce the level of required improvements to the existing
drainage system was considered at three locations in the basin. The diversion locations most
likely to significantly reduce the frequency and magnitude of flooding are along the south end
of the basin, near Anacortes Court NE and NE 10th Street. All three of these alternatives
propose diverting the runoff from sub-basins 12, 13, 14 and 15. This is a total area of
approximately 27 acres(43% of the project area), that contributes 20.7 cfs during the 100-
year design storm to the downstream trunk system. By alleviating 20.7 cfs of peak flow from
the system(47% of the sub-basin flow), the existing downstream trunk drainage system would
be adequate to provide a level of protection up to the 25-year event. For these alternatives,
potential flooding between manholes 8 and 9 in the 10-year event warrant the
recommendation that the existing siphon be replaced with at least a 24" diameter pipe. If this
alternative is pursued further, the option to install high-flow bypasses should be considered in
lieu of full diversions.
Alternative 3A-NE loth Street/North to Existing Creek and Arches
Description
Stormwater runoff north of drainage sub-basin 15 is presently conveyed from the area north of
NE 1 Oth Street (outside of the sub-basin boundaries), through a natural drainage along the
east fenceline of the Anacortes Avenue NE properties. This runoff appears to be discharged
to the pipe system denoted by the City as 9,C8-1 through 9,C8-5 (see Figure 3A)that
discharges downstream to the double corrugated metal arches (CMPAs) along Sunset
Boulevard. The pipes in this system are listed in the City's stormwater inventory attributes as
8" through 30" pipes. Through implementation of this alternative, this system would be
9
upgraded to allow passage of the maximum flow diverted from the project area's existing
system(20.7 cfs), as well as flows from other areas contributing to this reach. This alternative
offers the opportunity to incorporate a surface water storage element along the existing creek,
as well.
An estimated 24-inch parallel pipeline to the reach between manholes 3 and 2 would be
installed to convey runoff from areas 13 and 14 to the diversion structure at manhole 2. The
runoff from all four diverted basins would be conveyed by a 24-inch culvert discharging to a
level-spreader at the head of the existing creek. An alternative open channel could be
constructed north from the NE 10th right-of-way limit.
Table 3 lists the items associated with this improvement alternative.
Table 3
Alternative 3A : Diversion Piping and Existing Reach Upgrade
Information
Existing Replacement Average Length
Diameter Diameter Depth of Reach
Pipe Reach in in ft 11
mhl-2 12 18 10 590
mh3-2 12 24 5 455
mh2-Creek 30 5.5 230
Creek-Exist. 30 + 4 250
siphon 12 2 i es 24 6 30
Technical Feasibility
The feasibility of this alternative may be limited by existing creek topography, as compared to
required diversion elevations (this does not appear to be a problem). Inter jurisdictional issues
(diversion through King County), private property easement acquisitions and potential
sensitive area(e.g., wetland) interfaces may be concerns.
Benefits/Potential Impacts
Implementation of this alternative would provide protection to the level of the 100-year design
storm event.
This alternative would involve diversion of runoff across jurisdictional boundaries (from
Renton to King County and back to Renton). Easements would be required for private
property ownerships and sensitive areas. Potential impacts to the existing drainage course and
wetland would need to be considered if this alternative is analyzed further.
10
Estimated Cost
The preliminary order-of-magnitude construction cost of Alternative 3A is approximately
$280,000. Consideration of an open channel improvement north of NE 10th Street would
reduce costs.
Alternative 3B-NE loth Street/West to Union Avenue NE
The diversion of runoff to the existing drainage system aligned north-south along Union
Avenue was considered (See Figure 313). Not only would this alternative result in the inter-
basin diversion of runoff, it would not be feasible for gravity connection, based on the steep
grade along NE loth Street approaching Union. Pumping would be necessary to overcome
the adverse grade and would be infeasible at the required diversion flow rates. Therefore; this
alternative was not considered further.
Alternative 3C-NE 10th Street to Mission Hills Development (with Sub-
Surface Storage)
Description
Diversion of runoff to Mission Hills, the new development south of Anacortes Court NE, was
considered for Alternative 3C. To reduce the potential impact to the installed Mission Hill
drainage system, sub-surface storage similar to Alternative 2C would be implemented along
with the diversion.
A similar option, the diversion of flow from the southern-most catchbasin in Anacortes Court
NE, along the property-line and into the ditch behind the property line(with a tie to the
Mission Hills drainage system), was also considered. This alternative was not evaluated
further due to the limited capacities of the existing system to divert flows, the interbasin flow
diversion and the potential property owner easement issues.
Table 4
Alternative 3C: Diversion Piping and Existing Reach Upgrade
Information
Existing Replacement Average Length of
Diameter Diameter Depth Reach
Pipe Reach in in ft ft
mh 1-2 12 18 10 590
mh2- 12 18 4 215
Diversion
mh3- 12 24 4 240
Diversion
Diversion- -- 30 6 650
Mission Hills
siphon 12 2 i es 24 6 30
11
Feasibility
Feasibility of this alternative would be limited by downstream capacities of adjacent sub-basin
drainage reaches, legal issues regarding diversion and existing drainage system sizes and
grades.
BenefUs/Potendal Impacts
Implementation of this alternative would provide protection from events up to and including
the 100-year design storm.
The inter-basin diversion of flows could be an issue with this option, as the Mission Hills
system discharges to a biofiltration swale and ultimately a restrictive drainage way south of
the Honey Dew Creek Basin.
Estimated Cost
The preliminary order-of-magnitude construction cost of this alternative, including the sub-
surface storage of Alternative 3C, is approximately $600,000.
Conclusions
After review of these alternatives by City staff, two alternatives will be jointly selected for
further assessment. Based on the information presented in this technical memorandum, a
single conveyance and diversion alternative is suggested. A third alternative (possibly
combined conveyance and storage) could be considered, although this would extend beyond
the scope of work.
cAateresaVentonVnemo3_2.&c.
12
14
FIGURE53 � i d- SIZE
TABLE
TITLE
PRESENT LOCATION AND STATUS :
GENERAL DESCRIPTION AND IDENTIFYING CHARACTER:
PRINT OUTSIDE INSIDE
cl/7 41_ V
47
/� S� A7
STOR13 Chart 2
10-YR: Hydrograph for Node 3
12
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Page 1
STOR15 Chart 1
10-YR: Hydrograph for Node 5
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Page 1
STOR17 Chart 1
10-YR: Hydrograph for Node 7
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Time In Hours
Page 1
Appendix B
Hydraulic and Hydrologic Modeling Data—Input and Results
r f i n
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Hydrologic/Hydraulic Modelling Input Data and Results
Existing System Analysis
Input Data
• Basin Summary
• Reach Summary
• Structure Report
3/ 4/96 Ch2M Hill - Bellevue , WA page 1
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
---------------------------------------------------------------------
---------------------------------------------------------------------
BASIN SUMMARY
BASIN ID: BO NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 0 . 38 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 30 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 81 . 00
TIME OF CONC. . . . . : 68 . 07 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 0 . 08 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 220 . 00 ns : 0 . 4000 p2yr: 2 . 00 s : 0 . 0250
TcReach - Sheet L: 80 . 00 ns : 0 . 4100 p2yr: 2 . 00 s : 0 . 0250
TcReach - Shallow L: 20 . 00 ks : 11. 00 s : 0 . 0250
PEAK RATE: 0 . 14 cfs VOL: 0 . 07 Ac-ft TIME: 500 min
BASIN ID: B1 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 2 . 39 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 48 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 23 . 38 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 1 . 91 Acres
CN. . . . . 98. 00
TcReach - Sheet L: 100. 00 ns : 0 . 4000 p2yr: 2 . 00 s: 0 . 0400
TcReach - Sheet L: 200 . 00 ns: 0 . 0110 p2yr: 2. 00 s: 0 . 0400
TcReach - Shallow L: 250 . 00 ks : 27 . 00 s: 0 . 0400
PEAK RATE: 2. 08 cfs VOL: 0 . 67 Ac-ft TIME: 480 min
BASIN ID: B10 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 6 . 48 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 3 . 76 Acres
TIME INTERVAL. . . . . 10 . 00 min CN. . . . . 86. 00
TIME OF CONC. . . . . : 25 . 88 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 2 . 72 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 200 . 00 ns: 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Sheet L: 100 . 00 ns : 0 . 0110 p2yr: 2. 00 s : 0 . 0200
TcReach - Shallow L: 230 . 00 ks : 27 . 00 s: 0 . 0200
TcReach - Channel L: 80 . 00 kc : 42. 00 s: 0 . 0030
TcReach - Channel L: 250 . 00 kc : 42. 00 s: 0 . 0070
PEAK RATE: 4 . 74 cfs VOL: 1 . 57 Ac-ft TIME: 480 min
3/ 4/96 Ch2M Hill - Bellevue, WA page 2
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
---------------------------------------------------------------------
---------------------------------------------------------------------
BASIN SUMMARY
BASIN ID: B12 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 12 . 78 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 10 . 86 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 84 . 20
TIME OF CONC. . . . . : 41 . 20 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 1 . 92 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 300 . 00 ns : 0 . 1500 p2yr: 2. 00 s : 0 . 0200
TcReach - Shallow L: 125 . 00 ks : 11 . 00 s: 0 . 0200
TcReach - Shallow L: 545 . 00 ks : 5 . 00 s : 0 . 0350
TcReach - Shallow L: 70 . 00 ks : 27 . 00 s: 0 . 0200
PEAK RATE: 6 .42 cfs VOL: 2. 62 Ac-ft TIME: 490 min
BASIN ID: B13 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 8 . 15 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 5 . 05 Acres
TIME INTERVAL. . . . . 10 . 00 min CN. . . . . 86 . 00
TIME OF CONC. . . . . : 16. 93 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 3 . 10 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 50 . 00 ns: 0 . 1500 p2yr: 2. 00 s : 0 . 0200
TcReach - Channel L: 550 . 00 kc : 17 . 00 s: 0 . 0050
TcReach - Channel L: 550 . 00 kc :42 . 00 s: 0 . 0100
PEAK RATE: 6 . 29 cfs VOL: 1. 94 Ac-ft TIME: 470 min
BASIN ID: B14 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 1 . 16 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 63 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 17 . 07 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 0 . 53 Acres
CN. . . . . 98. 00
TcReach - Sheet L: 130 . 00 ns: 0 . 1500 p2yr: 2. 00 s: 0 . 0200
TcReach - Sheet L: 30 . 00 ns: 0 . 0110 p2yr: 2. 00 s: 0 . 0200.
TcReach - Channel L: 165 . 00 kc :42 . 00 s: 0 . 0030
PEAK RATE: 0 . 92 cfs VOL: 0 . 28 Ac-ft TIME: 470 min
3/ 4/96 Ch2M Hill - Bellevue, WA page 3
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
-----------
BASIN SUMMARY
BASIN ID: B15 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 4 . 96 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 3 . 57 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 60
TIME OF CONC. . . . . : 36 . 09 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0. 20 AREA. . : 1 . 39 Acres
CN. . . . : 98. 00
TcReach - Sheet L: 300 . 00 ns : 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Shallow L: 300 . 00 ks: 11. 00 s : 0. 0200
TcReach - Shallow L: 100 . 00 ks : 27 . 00 s : 0 . 0200
TcReach - Shallow L: 70 . 00 ks : 27 . 00 s: 0 . 0200
TcReach - Channel L: 330 . 00 kc : 17 . 00 s : 0 . 0200
PEAK RATE: 2. 98 cfs VOL: 1 . 15 Ac-ft TIME: 490 min
BASIN ID: B2 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 4 . 36 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 44 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 89 . 00
TIME OF CONC. . . . . : 14 . 37 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 3 . 92 Acres
CN. . . . : 98. 00
TcReach - Sheet L: 225 . 00 ns : 0 . 0110 p2yr: 2 . 00 s: 0 . 0200
TcReach - Sheet L: 75 . 00 ns : 0. 1500 p2yr: 2. 00 s: 0 . 0200
TcReach - Shallow L: 120. 00 ks : 27 . 00 s : 0. 0200
TcReach - Channel L: 380 . 00 kc : 42 . 00 s: 0. 0200
PEAK RATE: 4. 45 cfs VOL: 1. 29 Ac-ft TIME: 470 min
BASIN ID: B3 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 2. 54 Acres BASEFLOWS: 0. 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0. 51 Acres
TIME INTERVAL. . . . : 10. 00 min CN. . . . : 87. 00
TIME OF CONC. . . . . : 15 . 76 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 2. 03 Acres
CN. . . . : 98. 00
TcReach - Sheet L: 100 . 00 ns : 0. 1500 p2yr: 2. 00 s: 0 . 0200
TcReach - Sheet L: 200 . 00 ns : 0. 0110 p2yr: 2 . 00 s: 0 . 0200
TcReach - Shallow L: 400 . 00 ks : 67 . 20 s: 0. 0200
PEAK RATE: 2.42 cfs VOL: 0. 72 Ac-ft TIME: 470 min
3/ 4/96 Ch2M Hill - Bellevue , WA page 4
City of Renton: NE 10th Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
BASIN SUMMARY
BASIN ID: B4 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 2 . 19 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 .33 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 30
TIME OF CONC . . . . . : 14 . 03 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 1. 86 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 100 . 00 ns : 0 . 1500 p2yr: 2 . 00 s: 0 . 0200
TcReach - Sheet L: 50 . 00 ns : 0 . 0110 p2yr: 2 . 00 s : 0 . 0200
TcReach - Channel L: 270 . 00 kc : 42 . 00 s: 0 . 0200
PEAK RATE: 2 . 22 cfs VOL: 0 . 63 Ac-ft TIME: 470 min
BASIN ID: B5 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 2 . 38 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 24 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 87 . 00
TIME OF CONC. . . . . : 4. 81 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 2. 14 Acres
CN. . . . . 98. 00
TcReach - Sheet L: 300 . 00 ns : 0 . 0110 p2yr: 2. 00 s : 0. 0200
TcReach - Shallow L: 70 . 00 ks: 27 . 00 s: 0 . 0200
TcReach - Channel L: 290 . 00 kc : 42. 00 s : 0 . 0200
PEAK RATE: 2 . 90 cfs VOL: 0 . 70 Ac-ft TIME: 470 min
BASIN ID: B6 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 6. 13 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 3 . 56 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 21. 03 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 2. 57 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 150 . 00 ns: 0 . 1500 p2yr: 2 . 00 s: 0. 0200
TcReach - Sheet L: 150 . 00 ns : 0 . 0110 p2yr: 2. 00 s : 0 . 0200
TcReach - Shallow L: 60 . 00 ks : 27 . 00 s: 0 . 0200
TcReach - Channel L: 380 . 00 kc : 42. 00 s: 0 . 0100
PEAK RATE: 4 . 71 cfs VOL: 1 .48 Ac-ft TIME: 480 min
3/ 4/96 Ch2M Hill - Bellevue, WA page 5
City of Renton: NE 10th Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
---------------------------------------------------------------------
---------------------------------------------------------------------
BASIN SUMMARY
BASIN ID: B7 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 4 . 00 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 2 . 32 Acres
TIME INTERVAL. . . . . 10 . 00 min CN. . . . . 86 . 00
TIME OF CONC. . . . . : 24 . 87 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 1 . 68 Acres
CN. . . . . 98. 00
TcReach - Sheet L: 200 . 00 ns : 0 . 1500 p2yr: 2. 00 s : 0 . 0200
TcReach - Sheet L: 100 . 00 ns : 0 . 0110 p2yr: 2. 00 s : 0 . 0200
TcReach - Shallow L: 150 . 00 ks : 27 . 00 s : 0 . 0200
TcReach - Channel L: 224 . 00 kc : 42 . 00 s: 0 . 0065
PEAK RATE: 2. 98 cfs VOL: 0 . 97 Ac-ft TIME: 480 min
BASIN ID: B8 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 3 . 98 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 2 . 31 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86. 00
TIME OF CONC. . . . . : 24. 12 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 1 . 67 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 200 . 00 ns : 0 . 1500 p2yr: 2. 00 s: 0 . 0200
TcReach - Sheet L: 100 . 00 ns : 0 . 0110 p2yr: 2. 00 s: 0 . 0200
TcReach - Shallow L: 40 . 00 ks : 27 . 00 s : 0 . 0200
TcReach - Channel L: 210 . 00 kc :42. 00 s : 0 . 0100
PEAK RATE: 2 . 99 cfs VOL: 0 . 96 Ac-ft TIME: 480 min
BASIN ID: B9 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 1 .46 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 85 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 19 . 46 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 0 . 61 Acres
CN. . . . . 98 . 00
PEAK RATE: 1 . 12 cfs VOL: 0 . 35 Ac-ft TIME: 480 min
3/ 4/96 Ch2M Hill - Bellevue, WA page 2
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
REACH SUMMARY
PIPE REACH ID No. pl
From: mhl To: mh2
Pipe Diameter: 1 . 00 ft n: 0 . 0120
Pipe Length 590 . 17 ft s : 0 . 0293
Up invert 426 . 11 ft down invert: 408 . 80
Collection Area: 12. 78 Ac.
Design Flow 6.42 cfs Dsgn Depth: 0. 21 ft
Pipe Capacity 7 . 13 cfs
Design Vel 9. 61 fps Travel Time: 1. 02 min
Pipe Full Vel 9 . 32 fps
3/ 4/96 Ch2M Hill - Bellevue, WA page 3
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
REACH SUMMARY
PIPE REACH ID No. p10
From: cb10 To:
Pipe Diameter: 0 . 00 ft n: 0 . 0000
Pipe Length 0 . 00 ft s : 0 . 0000
Up invert ft down invert:
Collection Area: Ac .
Design Flow cfs Dsgn Depth: ft
Pipe Capacity cfs
Design Vel fps Travel Time: min
Pipe Full Vel fps
PIPE REACH ID No. p11
From: To: cbll
Pipe Diameter: 0 . 00 ft n: 0 . 0000
Pipe Length 0 . 00 ft s : 0 . 0000
Up invert ft down invert:
Collection Area: Ac .
Design Flow cfs Dsgn Depth: ft
Pipe Capacity cfs
Design Vel fps Travel Time: min
Pipe Full Vel fps
PIPE REACH ID No. p2
From: mh2 To: mh3
Pipe Diameter: 1 . 00 ft n: 0 . 0120
Pipe Length 455 . 00 .ft s : 0 . 0069
Up invert 408 . 78 ft down invert: 405 . 63
Collection Area: 17 . 74 Ac .
Design Flow 9 . 40 cfs Dsgn Depth: ft
Pipe Capacity 3 . 46 cfs
Design Vel 11 . 96 fps Travel Time: 0 . 63 min
Pipe Full Vel 4. 53 fps
(surcharged tt)
PIPE REACH ID No. p3
From: mh3 To: mh4
Pipe Diameter: 1 . 50 ft n: 0 . 0120
Pipe Length 308. 16 ft s: 0 . 0054
Up invert 406 . 56 ft down invert: 404 . 89
Collection Area: 27. 05 Ac.
Design Flow 15 . 95 cfs Dsgn Depth: ft
Pipe Capacity 9 . 04 cfs
Design Vel 9 . 03 fps Travel Time: 0 . 57 min
Pipe Full Vel 5 . 25 fps
(surcharged tt)
3/ 4/96 Ch2M Hill - Bellevue , WA page 4
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
REACH SUMMARY
PIPE REACH ID No. p4
From: mh4 To: mh5
Pipe Diameter: 1 . 50 ft n: 0 . 0120
Pipe Length 260 . 05 ft s : 0 . 0034
Up invert 404 . 40 ft down invert: 403 . 52
Collection Area: 33 . 53 Ac .
Design Flow 20 . 70 cfs Dsgn Depth: ft
Pipe Capacity 7 . 14 cfs
Design Vel 11. 71 fps Travel Time: 0 . 37 min
Pipe Full Vel 4 . 15 fps
(surcharged tt)
PIPE REACH ID No. p5
From: mh5 To: mh6
Pipe Diameter: 1 . 50 ft n: 0 . 0120
Pipe Length 410 . 12 ft s: 0 . 0040
Up invert 403 .45 ft down invert: 401 . 83
Collection Area: 38 . 97 Ac .
Design Flow 24. 81 cfs Dsgn Depth: ft
Pipe Capacity 7 . 71 cfs
Design Vel 14. 04 fps Travel Time: 0 .49 min
Pipe Full Vel 4 . 48 fps
(surcharged tt)
PIPE REACH ID No. p6
From: mh6 To: mh7
Pipe Diameter: 1. 50 ft n: 0 . 0120
Pipe Length 245. 05 ft s: 0 . 0110
Up invert 401. 62 ft down invert: 398.92
Collection Area: 49 . 10 Ac.
Design Flow 32 . 50 cfs Dsgn Depth: ft
Pipe Capacity 12. 88 cfs
Design Vel 18. 39 fps Travel Time: 0 . 22 min
Pipe Full Vel 7 . 48 fps
(surcharged tt)
PIPE REACH ID No. p7
From: mh7 To: mh8
Pipe Diameter: 1 . 50 ft n: 0 . 0120
Pipe Length 115 . 35 ft s: 0 . 0343
Up invert 398. 74 ft down invert: 394. 78
Collection Area: 53 . 67 Ac.
Design Flow 35 . 81 cfs Dsgn Depth: ft
Pipe Capacity 22 . 74 cfs
Design Vel 20 . 26 fps Travel Time: 0 . 09 min
Pipe Full Vel 13 . 21 fps
(surcharged tt)
3/ 4/96 Ch2M Hill - Bellevue , WA page 5
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
REACH SUMMARY
PIPE REACH ID No. p8
From: mh8 To: mh9
Pipe Diameter: 1 . 50 ft n: 0 . 0120
Pipe Length 251 . 91 ft s : 0 . 0188
Up invert 394 . 78 ft down invert: 390 . 05
Collection Area: 60 . 57 Ac .
Design Flow 41 . 78 cfs Dsgn Depth: ft
Pipe Capacity 16 . 82 cfs
Design Vel 23 . 64 fps Travel Time: 0 . 18 min
Pipe Full Vel 9 . 77 fps
(surcharged tt)
PIPE REACH ID No. p9
From: mh9 To: mh10
Pipe Diameter: 2. 00 ft n: 0 . 0120
Pipe Length 60 . 01 ft s: 0 . 0130
Up invert 390 . 05 ft down invert: 389 . 27
Collection Area: 62. 96 Ac .
Design Flow 43 . 85 cfs Dsgn Depth: ft
Pipe Capacity 30 . 14 cfs
Design Vel 13 . 96 fps Travel Time: 0 . 07 min
Pipe Full Vel 9 . 85 fps
(surcharged tt)
3/ 4/96 Ch2M Hill - Bellevue , WA page 1
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
----------------------=----------------------------------------------
---------------------------------------------------------------------
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mhl
Location : Node 14 , D4-1 North 555 . 0000
Str Type : --- East 1910 . 0000
Str Cat : Stm Manhole Rim Elev 437 . 8200
Str Diam : 48 . 00 in Bottom El: 426 . 1100
Cont Area: B12 Hgrade El: 430 . 3437 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 518 Exit: 1. 036 App Vel: 0 . 000 Junct: 0 . 000 Bend: 0 . 000
Reach <Invert> <Diam> < n > <End>
pl 426 . 110 12. 00 0 . 012 Upper
EXISTING STRUCTURE REACH ID No. mh10
Location : Node 9 , C8-19 North 1950 . 0000
Str Type : --- East 671 . 0000
Str Cat : Stm Manhole Rim Elev 395 . 0800
Str Diam : 48 . 00 in Bottom E1: 389 . 2700
Cont Area: Hgrade E1: 395 . 5800 ft
Bend. . . . . : No special shape
Ent type. : Str Diam
Ent Loss : 0 . 000 Exit: 0. 000 App Vel: 0 . 000 Junct: 0 . 000 Bend: 0 . 000
Reach <Invert> <Diam> < n > <End>
p9 389 . 270 24. 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh2
Location : Node 14 , D4-3 North 569 . 0000
Str Type : --- East 1320 . 0000
Str Cat : Stm Manhole Rim Elev 412.4700
Str Diam : 48. 00 in Bottom El: 408. 7800
Cont Area: B15 Hgrade El: 412. 5700 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss: 1 . 111 Exit: 2. 222 App Vel: 1 . 036 Junct: 0 . 327 Bend: 0 . 009
Reach <Invert> <Diam> < n > <End>
p2 408 . 780 12. 00 0. 012 Upper
pl 408 . 803 12. 00 0 . 012 Lower
3/ 4/96 Ch2M Hill - Bellevue, WA page 2
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
---------------------------------------------------------------------
---------------------------------------------------------------------
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mh3
Location : Node 14 , C4-2 North 567 . 0000
Str Type : --- East 865 . 0000
Str Cat : Stm Manhole Rim Elev 409 . 8800
Str Diam : 48 . 00 in Bottom El: 405 . 6300
Cont Area: B14 Hgrade El : 409 . 9800 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss: 0 . 633 Exit: 1 . 266 App Vel: 2 . 222 Junct: 0 . 958 Bend: 2. 958
Reach <Invert> <Diam> < n > <End>
p3 406. 560 18 . 00 0 . 012 Upper
p2 405 . 630 12. 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh4
Location : Node 14 , C3-2 North 875 . 0000
Str Type : --- East 875 . 0000
Str Cat : Stm Manhole Rim Elev 412. 2300
Str Diam : 48. 00 in Bottom El: 404. 4000
Cont Area: B10 Hgrade El: 412. 3300 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss: 1 . 065 Exit: 2. 130 App Vel: 1 . 266 Junct: 0 . 275 Bend: 1. 685
Reach <Invert> <Diam> < n > <End>
p4 404.400 18 . 00 0 . 012 Upper
p3 404 . 890 18 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh5
Location : Node 14,C3-4 North 870 . 0000
Str Type : --- East 615 . 0000
Str Cat : Stm Manhole Rim Elev 413 . 5800
Str Diam : 48 . 00 in Bottom El: 403 . 4500
Cont Area: B9 Hgrade El: 413 . 6800 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss: 1 . 530 Exit: 3 . 060 App Vel: 2 . 130 Junct: 0 . 324 Bend: 2. 835
Reach <Invert> <Diam> < n > <End>
p5 403 .450 18 . 00 0 . 012 Upper
p4 403 . 520 18 . 00 0 . 012 Lower
3/ 4/96 Ch2M Hill - Bellevue , WA page 3
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mh6
Location : Node 14 , C3-10 North 1280 . 0000
Str Type : --- East 625 . 0000
Str Cat : Stm Manhole Rim Elev 411 . 9200
Str Diam : 48 . 00 in Bottom El: 401 . 6200
Cont Area: B7 Hgrade El: 412 . 0200 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 2 . 626 Exit: 5 . 251 App Vel: 3 . 060 Junct: 0 . 690 Bend: 0 . 012
Reach <Invert> <Diam> < n > <End>
p6 401 . 620 18 . 00 0 . 012 Upper
p5 401 . 830 18 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh7
Location : Node 14 , C2-7 North 1525 . 0000
Str Type : --- East 630 . 0000
Str Cat : Stm Manhole Rim Elev 404. 8100
Str Diam : 48 . 00 in Bottom El: 398. 7400
Cont Area: B5 Hgrade El: 404 . 9100 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss: 3 . 188 Exit: 6. 376 App Vel: 5 . 251 Junct: 0 .430 Bend: 0 . 074
Reach <Invert> <Diam> < n > <End>
p7 398 . 740 18 . 00 0 . 012 Upper
p6 398. 920 18 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh8
Location : Node 14,C2-4 North 1640 . 0000
Str Type : --- East 639 . 0000
Str Cat : Stm Manhole Rim Elev : 399 . 8200
Str Diam : 48 . 00 in Bottom El: 394. 7800
Cont Area: B3 Hgrade El: 399 . 9200 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss: 4 . 339 Exit: 8 . 678 App Vel: 6 . 376 Junct: 0 . 827 Bend: 0 . 074
Reach <Invert> <Diam> < n > <End>
p8 394 . 780 18. 00 0 . 012 Upper
p7 394 . 780 18. 00 0 . 012 Lower
3/ 4/96 Ch2M Hill - Bellevue, WA page 4
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mh9
Location : Node 9 , C8-18 North 1890 . 0000
Str Type : --- East 670 . 0000
Str Cat : Stm Manhole Rim Elev 395 . 5800
Str Diam : 48 . 00 in Bottom El: 390 . 0500
Cont Area: B1 Hgrade El: 393 . 9277 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 1 . 513 Exit: 3 . 026 App Vel: 8 . 678 Junct: 0 . 356 Bend: 0 . 221
Reach <Invert> <Diam> < n > <End>
p9 390 . 050 24 . 00 0 . 012 Upper
p8 390 . 050 18. 00 0 . 012 Lower
Results
• History of Hydrograph Activity
3/ 4/96 Ch2M Hill - Bellevue, WA page 1
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
HISTORY OF HYDROGRAPH ACTIVITY
Date of Session: 6/22/95
CLEARHIS
ZERO 1 20
REMARK *trx**rt*r*rt*****rt*trtwr►r**r*rr*** *r****r***tr**r**t*r* ****e**
START OUT BY ROUTING THE 2 YEAR STORM THROUGH HYDROGRAPH 1
LSTEND
CHANGE "2 YR STORM" 2.00 PRECIP
BO B1 B10 812 813 B14
B15 B2 B3 B4 B5 B6
B7 88 B9
LSTEND
ROUTE HYDROGRAPH 1 THROUGH REACH pl
Reach -Area- --Qact-- --QFuLL- %Full Ndepth --Dia- -Vact- -VfuLL Basn
p1 12.78 1.93 7.13 27.03 4.43 12.00 7.31 8.44 B12
ROUTE HYDROGRAPH 1 THROUGH REACH p2
Reach -Area- --pact-- --QFuIL- %Full Ndepth --Dia- -Vact- -Vfull Basn
p2 17.74 3.00 3.46 86.57 9.17 12.00 4.66 4.10 B15
ADD 1 B13 1
5.0704 cfs 2.1161 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 1 THROUGH REACH p3
Reach -Area- --Qact-- --QFull- %FuIL Ndepth --Dia- -Vact- -Vfull Basn
p3 27.05 5.42 9.04 60.00 10.52 18.00 5.05 4.75 B14
ROUTE HYDROGRAPH 1 THROUGH REACH p4
Reach -Area- --Qact-- --QFull- %Full Ndepth --Dia- -Vact- -Vfull Basn
p4 33.53 7.21 --------Pressure Flow-------- 4.08 B10
ADD 1 B8 1
8.3410 cfs 3.2380 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 1 THROUGH REACH p5
Reach -Area- --Qact-- --QFull- %Full Ndepth --Dia- -Vact- -Vfull Basn
p5 38.97 8.77 --------Pressure Flow-------- 4.96 B9
ADD 1 B6 1
10.5587 cfs 3.9682 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 1 THROUGH REACH p6
Reach -Area- --Qact-- --QFull- %FuIL Ndepth --Dia- -Vast- -Vfull Basn
p6 49.10 11.69 12.88 90.70 14.37 18.00 7.72 6.78 B7
ADD 1 B4 1
12.5572 cfs 4.6431 ac-ft 8.00 hrs
3/ 4/96 Ch2M Hill - Bellevue, WA page 2
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
HISTORY OF HYDROGRAPH ACTIVITY
ROUTE HYDROGRAPH 1 THROUGH REACH p7
Reach -Area- --Qact-- --QFull- %full Ndepth --Dia- -Vact- -Vfull Basn
p7 53.67 13.26 22.74 58.33 7.66 18.00 12.63 11.96 B5
ADD 1 B2 1
15.0918 cfs 5.5763 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 1 THROUGH REACH p8
Reach -Area- --Qact-- --QFull- %FULL Ndepth --Dia- -Vact- -Vfull Basn
p8 60.57 16.11 16.82 95.77 2.70 18.00 10.06 8.85 B3
ROUTE HYDROGRAPH 1 THROUGH REACH p9
Reach -Area- --Qact-- --QFull- %Full Ndepth --Dia- -Vact- -Vfull Basn
p9 62.96 17.06 30.14 56.60 10.48 24.00 9.35 8.92 B1
HGRADE hgradel
n1
SUBMERGED 393.95
LSTEND
HGLINE hgradel
Hydraulic Gradeline for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent_HGL EntLoss ExtLoss OutLet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
mh10 393.95
mh9 mh10 17.06 0.29 394.24 0.23 0.46 394.93 392.12 1.29 0.03 0.06 393.73 395.58
mh8 mh9 16.11 5.02 398.75 0.65 1.29 400.69 399.08 0.87 0.01 0.14 399.92* 399.82
mh7 mh8 13.26 1.56 401.48 0.44 0.87 402.79 401.96 0.68 0.01 0.07 402.19 404.81
mh6 mh7 11.69 2.57 404.76 0.34 0.68 405.78 404.36 0.38 0.00 0.09 405.49 411.92
mh5 mh6 8.T7 2.42 407.92 0.19 0.38 408.49 405.43 0.26 0.34 0.04 408.62 413.58
mho mh5 7.21 1.04 409.66 0.13 0.26 410.04 405.04 0.15 0.19 0.03 410.13 412.23
mh3 mho 5.42 0.70 410.82 0.07 0.15 411.04 407.04 0.23 0.30 0.11 409.98* 409.88
mh2 mh3 3.00 2.T3 412.T1 0.11 0.23 413.05 409.78 0.09 0.00 0.03 412.57* 412.47
mhl mh2 1.93 1.46 414.03 0.05 0.09 414.17 426.41 0.00 0.00 0.00 426.41 437.82
REMARK
ROUTING THE 10 YEAR STORM THROUGH HYDROGRAPH 2
LSTEND
CHANGE "10 YR STORM" 2.90 PRECIP
BO B1 B10 B12 813 B14
B15 B2 B3 B4 B5 B6
B7 B8 B9
LSTEND
ROUTE HYDROGRAPH 2 THROUGH REACH pl
Reach -Area- --Qact-- --QFull- %Full Ndepth --Dia- -Vact- -Vfull Basn
p1 12.78 3.95 7.13 55.48 5.32 12.00 8.81 8.44 B12
3/ 4/96 Ch2M Hill - Bellevue, WA page 3
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
HISTORY OF HYDROGRAPH ACTIVITY
ROUTE HYDROGRAPH 2 THROUGH REACH p2
Reach -Area- --Qact-- --QFuIL- %Full Ndepth --Dia- -Vact- -VfuLL Basn
p2 17.74 5.91 --------Pressure Flow-------- 7.53 B15
ADD 2 B13 2
9.6485 cfs 3.7615 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 2 THROUGH REACH p3
Reach -Area- --Qact-- --QFuIL- %Full Ndepth --Dia- -Vact- -VfuLL Basn
p3 27.05 10.26 --------Pressure Flow-------- 5.80 B14
ROUTE HYDROGRAPH 2 THROUGH REACH p4
Reach -Area- --Qact-- --QFuIL- %Full Ndepth --Dia- -Vact- -VfuLL Basn
p4 33.53 13.42 --------Pressure Flow-------- 7.60 B10
ADD 2 B8 2
15.4218 cfs 5.6671 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 2 THROUGH REACH p5
Reach -Area- --Qact-- --QFuIL- %Full Ndepth --Dia- -Vact- -VfuLL Basn
p5 38.97 16.18 --------Pressure flow-------- 9.15 B9
ADD 2 B6 2
19.3295 cfs 6.9087 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 2 THROUGH REACH p6
Reach -Area- --Qact-- --QFuLL- %Full Ndepth --Dia- -Vact- =VNL L Basn
p6 49.10 21.32 --------Pressure Flow-------- 12.07 B7
ADD 2 B4 2
22.6605 cfs 8.0133 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 2 THROUGH REACH p7
Reach -Area- --Qact-- --QFuLI- %FuIL Ndepth --Dia- -Vact- -Vfull Basn
p7 53.67 23.73 --------Pressure flow-------- 13.43 85
ADD 2 B2 2
26.4822 cfs 9.4419 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 2 THROUGH REACH p8
Reach -Area- --Qact-- --QFuIL- %FuIL Ndepth --Dia- -Vact- -VfuLL Basn
p8 60.57 28.06 --------Pressure Flow-------- 15.88 B3
ROUTE HYDROGRAPH 2 THROUGH REACH p9
Reach -Area- --Qact-- --QFull- %FuIL Ndepth --Dia- -Vact- -VfuLL Basn
p9 62.96 29.55 30.14 98.04 2.87 24.00 10.09 8.92 81
HGRADE hgradel
n1
SUBMERGED 395.58
3/ 4/96 Ch2M Hill - Bellevue, WA page 4
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
---------------------------------------------------------------------
---------------------------------------------------------------------
HISTORY OF HYDROGRAPH ACTIVITY
LSTEND
HGLINE hgradel
Hydraulic GradeLine for Reach hgradel
<-FROM-> <--TO--> <FLOW floss Ent_HGL EntLoss ExtLoss OutLet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
mh10 395.58
mh9 mh10 29.55 0.87 396.45 0.69 1.37 398.51 394.90 3.92 0.10 0.17 394.86 395.58
mh8 mh9 28.06 15.23 410.10 1.96 3.92 415.97 405.81 2.80 0.03 0.39 399.92* 399.82
mh7 mh8 23.73 4.99 404.91 1.40 2.80 409.11 406.89 2.26 0.03 0.20 404.91* 404.81
mh6 mh7 21.32 8.56 413.47 1.13 2.26 416.86 408.41 1.30 0.01 0.30 412.02* 411.92
mh5 mh6 16.18 8.24 420.26 0.65 1.30 422.21 407.79 0.90 1.19 0.14 413.68* 413.58
mho mh5 13.42 3.60 417.28 0.45 0.90 418.62 407.70 0.52 0.70 0.12 412.33* 412.23
mh3 mho 10.26 2.49 414.82 0.26 0.52 415.60 408.90 0.88 1.17 0.39 409.98* 409.88
mh2 mh3 5.91 10.62 420.60 0.44 0.88 421.91 411.70 0.39 0.00 0.13 412.57* 412.47
mhl mh2 3.95 6.16 418.73 0.20 0.39 419.32 427.77 0.00 0.00 0.00 427.77 437.82
REMARK
ROUTING THE 25 YEAR STORM THROUGH HYDROGRAPH 3
LSTEND
CHANGE "25 YR STORM" 3.40 PRECIP
BO B1 B10 B12 B13 B14
B15 B2 B3 B4 B5 B6
B7 B8 B9
LSTEND
ROUTE HYDROGRAPH 3 THROUGH REACH pl
Reach -Area- --Qact-- --QFuIL- %FuLL Ndepth --Oia- -Vact- -VfuLL Basn
p1 12.78 5.17 7.13 72.49 4.03 12.00 9.33 8.44 B12
ROUTE HYDROGRAPH 3 THROUGH REACH p2
Reach -Area- --Qact-- --QFult- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p2 17.74 7.63 --------Pressure Flow-------- 9.72 B15
ADD 3 B13 3
12.3276 cfs 4.7244 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 3 THROUGH REACH p3
Reach -Area- --Qact-- --QFull- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p3 27.05 13.08 --------Pressure Flow-------- 7.40 B14
ROUTE HYDROGRAPH 3 THROUGH REACH p4
Reach -Area- --Qact-- --QFull- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p4 33.53 17.03 --------Pressure Flow-------- 9.64 B10
ADD 3 B8 3
19.5242 cfs 7.0806 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 3 THROUGH REACH p5
3/ 4/96 Ch2M Hill - Bellevue , WA page 5
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
HISTORY OF HYDROGRAPH ACTIVITY
Reach -Area- --Qact-- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p5 38.97 20.46 --------Pressure Flow-------- 11.58 B9
ADD 3 B6 3
24.3924 cfs 8.6163 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 3 THROUGH REACH p6
Reach -Area- --Qact-- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p6 49.10 26.88 --------Pressure Flow-------- 15.21 B7
ADD 3 B4 3
28.4731 cfs 9.9655 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 3 THROUGH REACH p7
Reach -Area- --Qact-- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p7 53.67 29.74 --------Pressure Flow-------- 16.83 B5
ADD 3 B2 3
33.0031 cfs 11.6709 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 3 THROUGH REACH p8
Reach -Area- --Qact-- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p8 60.57 34.89 --------Pressure Flow-------- 19.74 B3
ROUTE HYDROGRAPH 3 THROUGH REACH p9
Reach -Area- --Qact-- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p9 62.96 36.67 --------Pressure Flow-------- 11.67 B1
HGRADE hgradel
n1
SUBMERGED 395.58
LSTEND
HGLINE hgradel
Hydraulic Gradeline for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent_HGL EntLoss ExtLoss OutLet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
mh10 395.58
mh9 mh10 36.67 1.34 396.92 1.06 2.12 400.09 396.80 6.05 0.15 0.26 394.45 395.58
mh8 mh9 34.89 23.55 418.00 3.03 6.05 427.08 411.29 4.40 0.05 0.59 399.92* 399.82
mh7 mh8 29.74 7.84 407.76 2.20 4.40 414.35 410.99 3.59 0.05 0.31 404.91* 404.81
mh6 mh7 26.88 13.60 418.51 1.80 3.59 423.90 411.82 2.08 0.01 0.47 412.02* 411.92
mh5 mh6 20.46 13.19 425.21, 1.04 2.08 428.33 409.79 1.44 1.92 0.22 413.68* 413.58
mho mh5 17.03 5.79 419.47 0.72 1.44 421.64 409.10 0.85 1.13 0.19 412.33* 412.23
mh3 mh4 13.08 4.05 416.38 0.43 0.85 417.66 409.74 1.47 1.95 0.64 409.98* 409.88
mh2 mh3 7.63 17.70 427.68 0.73 1.47 429.88 413.21 0.67 0.01 0.22 412.57* 412.47
mhl mh2 5.17 10.52 423.09 0.34 0.67 424.10 428.49 0.00 0.00 0.00 428.49 437.82
REMARK
ROUTING THE 100 YEAR STORM THROUGH HYDROGRAPH 3
3/ 4/96 Ch2M Hill - Bellevue, WA page 6
City of Renton: NE loth Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
HISTORY OF HYDROGRAPH ACTIVITY
LSTEND
CHANGE "100 YR PRECIP" 3.90 PRECIP
BO B1 B10 B12 B13 B14
B15 B2 B3 B4 B5 B6
B7 B8 B9
LSTEND
ROUTE HYDROGRAPH 4 THROUGH REACH pl
Reach -Area- --pact-- --QFuLL- %Full Ndepth --Dia- -Vact- -VfuLL Basn
p1 12.78 6.42 7.13 89.99 2.49 12.00 9.61 8.44 B12
ROUTE HYDROGRAPH 4 THROUGH REACH p2
Reach -Area- --Qact-- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p2 17.74 9.40 --------Pressure Flow-------- 11.96 B15
ADD 4 B13 4
15.0557 cfs 5.7089 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 4 THROUGH REACH p3
Reach -Area- --Qact-- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p3 27.05 15.95 --------Pressure Flow-------- 9.03 B14
ROUTE HYDROGRAPH 4 THROUGH REACH p4
Reach -Area- --Qact- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p4 33.53 20.TO --------Pressure Flow-------- 11.71 B10
ADD 4 B8 4
23.6829 cfs 8.5222 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 4 THROUGH REACH p5
Reach -Area- --Qact-- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p5 38.97 24.81 --------Pressure Flow-------- 14.04 B9
ADD 4 B6 4
29.5162 cfs 10.3562 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 4 THROUGH REACH p6
Reach -Area- --Qact-- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p6 49.10 32.50 --------Pressure Flow-------- 18.39 87
ADD 4 B4 4
34.3476 cfs 11.9526 ac-ft 8.00 hrs
ROUTE HYDROGRAPH 4 THROUGH REACH p7
Reach -Area- --Qact-- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p7 53.67 35.81 --------Pressure Flow-------- 20.26 B5
ADD 4 B2 4
39.5826 cfs 13.9352 ac-ft 8.00 hrs
3/ 4/96 Ch2M Hill - Bellevue , WA page 7
City of Renton: NE 10th Street/Anacortes Ct. NE
Storm System Improvement Project
Existing System Analysis
HISTORY OF HYDROGRAPH ACTIVITY
ROUTE HYDROGRAPH 4 THROUGH REACH p8
Reach -Area- --Qact-- --QFult- %Full Ndepth --Dia- -Vact- -VfuLL Basn
p8 60.57 41.78 --------Pressure FLow-------- 23.64 B3
ROUTE HYDROGRAPH 4 THROUGH REACH p9
Reach -Area- --Qact-- --QFuLL- %FuLL Ndepth --Dia- -Vact- -VfuLL Basn
p9 62.96 43.85 --------Pressure Flow-------- 13.96 B1
HGRADE hgradel
n1
SUBMERGED 395.58
LSTEND
HGLINE hgradel
Hydraulic Gradeline for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent-HGL EntLoss ExtLoss OutLet Intet AppHead BndHead JunHead HeadWtr -cb/mh-
mh10 395.58
mh9 mh10 43.85 1.91 397.49 1.51 3.03 402.03 399.13 8.68 0.22 0.36 393.93 395.58
mh8 mh9 41.78 33.77 427.70 4.34 8.68 440.72 418.01 6.38 0.07 0.83 399.92* 399.82
mh7 mh8 35.81 11.36 411.28 3.19 6.38 420.85 416.06 5.25 0.07 0.43 404.91* 404.81
mh6 mh7 32.50 19.88 424.79 2.63 5.25 432.66 416.08 3.06 0.01 0.69 412.02* 411.92
mh5 mh6 24.81 19.38 431.40 1.53 3.06 435.99 412.29 2.13 2.83 0.32 413.68* 413.58
mho mh5 20.70 8.55 422.23 1.06 2.13 425.43 410.86 1.27 1.68 0.28 412.33* 412.23
mh3 mh4 15.95 6.02 418.35 0.63 1.27 420.25 410.81 2.22 2.96 0.96 409.98* 409.88
mh2 mh3 9.40 26.82 436.80 1.11 2.22 440.13 415.14 1.04 0.01 0.33 412.57* 412.47
mhl mh2 6.42 16.22 428.79 0.52 1.04 430.34 429.42 0.00 0.00 0.00 430.34 437.82
End program file BASIN O.PGM
Hydrologic/Hydraulic Modelling Input Data and Results
Alternative 1 B, Conveyance: Anacortes Avenue NE Bypass
with Trunk Storm Drain Reach Replacements
1/ 7/96 Ch2M Hill - Bellevue , WA page 10
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass-
---------------------------------------------------------------------
---------------------------------------------------------------------
REACH SUMMARY
PIPE REACH ID No. p7
From: mh7 To: mh8
Pipe Diameter: 2 . 50 ft n: 0 . 0120
Pipe Length 120 . 42 ft s : 0 . 0259
Up invert 397 . 76 ft down invert: 394 . 64
Collection Area: 51 . 54 Ac .
Design Flow 34 . 63 cfs Dsgn Depth: 1 . 22 ft
Pipe Capacity 77 . 15 cfs
Design Vel 14 . 48 fps Travel Time: 0 . 14 min
Pipe Full Vel 16 . 13 fps
PIPE REACH ID No. p8
From: mh8 To: mh9
Pipe Diameter: 3 . 00 ft n: 0 . 0120
Pipe Length 250 . 20 ft s : 0 . 0189
Up invert 394 . 54 ft down invert: 389 . 82
Collection Area: 58 . 44 Ac .
Design Flow 40 . 70 cfs Dsgn Depth: 1 . 34 ft
Pipe Capacity 107 . 04 cfs
Design Vel 13 . 37 fps Travel Time: 0 . 31 min
Pipe Full Vel 15 . 54 fps
PIPE REACH ID No. p9
From: mh9 To: mh10
Pipe Diameter: 3 . 00 ft n: 0 . 0120
Pipe Length 90 . 00 ft s : 0 . 0134
Up invert 389 . 72 ft down invert: 388 . 51
Collection Area: 60 . 83 Ac .
Design Flow 42 . 78 cfs Dsgn Depth: 1 . 48 ft
Pipe Capacity 90 . 37 cfs
Design Vel 11 . 94 fps Travel Time: 0 . 13 min
Pipe Full Vel 13 . 12 fps
1/ 7/96 Ch2M Hill - Bellevue , WA page 11
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. junction
Location : Junction Structure to Arches North 1980 . 0000
Str Type : East 565 . 0000
Str Cat : Dummy Structure Rim Elev 392 . 0000
Str Diam : 72 . 00 in Bottom E1 : 388 . 0800
Cont Area: Hgrade El : 391 . 5800 ft
Bend. . . . . : No special shape
Ent type . : Str Diam :
Ent Loss : 0 . 181 Exit: 0 . 362 App Vel: 0 . 276 Junct: 0 . 031 Bend: 0 . 336
Reach <Invert> <Diam> < n > <End>
p13 388 . 080 36 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh1
Location : Node 14 , D4-1 North 555 . 0000
Str Type : --- East 1910 . 0000
Str Cat : Stm Manhole Rim Elev 437 . 8200
Str Diam : 48 . 00 in Bottom El: 426 . 1100
Cont Area: B12 Hgrade El: 429 . 4199 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 518 Exit: 1 . 036 App Vel: 0 . 000 Junct: 0 . 000 Bend: 0 . 000
Reach <Invert> <Diam> < n > <End>
pl 426 . 110 12 . 00 0 . 012 Upper
EXISTING STRUCTURE REACH ID No. mh10
Location : Node 9 ,C8-19 North 1980 . 0000
Str Type : --- East 650 . 0000
Str Cat : Stm Manhole Rim Elev 394 . 8500
Str Diam : 60 . 00 in Bottom El: 388 .4100
Cont Area: Hgrade El: 392 . 9175 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 284 Exit: 0 . 569 App Vel: 0 . 569 Junct: 0 . 000 Bend: 0 . 757
Reach <Invert> <Diam> < n > <End>
p9 388. 510 36. 00 0 . 012 Lower
p13 388 .410 36. 00 0 . 012 Upper
1/ 7/96 Ch2M Hill - Bellevue , WA page 12
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
---------------------------------------------------------------------
---------------------------------------------------------------------
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mh2
Location Node 14 , D4-3 North 569 . 0000
Str Type --- East 1320 . 0000
Str Cat Stm Manhole Rim Elev 412 . 4700
Str Diam 48 . 00 in Bottom El: 407 . 1700
Cont Area: B15 Hgrade El : 410 . 2962 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 219 Exit: 0 . 439 App Vel : 1 . 036 Junct: 0 . 327 Bend: 0 . 008
Reach <Invert> <Diam> < n > <End>
p2 407 . 170 18 . 00 0 . 012 Upper
pl 407 . 270 12 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh3
Location : Node 14 . C4-2 North 567 . 0000
Str Type : East 865 . 0000
Str Cat : Stm Manhole Rim Elev 409 . 8800
Str Diam : 48 . 00 in Bottom El: 406 . 5600
Cont Area: B14 Hgrade El : 407 . 3811 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss: 0 . 041 Exit: 0 . 081 App Vel: 0 . 000 Junct: 0 . 000 Bend: 0 . 000
Reach <Invert> <Diam> < n > <End>
p3 406 . 560 24 . 00 0 . 012 Upper
EXISTING STRUCTURE REACH ID No. mh5
Location Node 14 .C3-4 North 870 . 0000
Str Type East 615 . 0000
Str Cat Stm Manhole Rim Elev 413 . 5800
Str Diam 48 . 00 in Bottom El: 403 . 4500
Cont Area: B9 Hgrade E1 : 404 . 4693 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss: 0 . 041 Exit: 0 . 083 App Vel: 0 . 000 Junct: 0 . 000 Bend: 0 . 000
Reach <Invert> <Diam> < n > <End>
p5 403 . 450 18 . 00 0 . 012 Upper
1/ 7/96 Ch2M Hill - Bellevue, WA page 13
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mh6
Location : Node 14 , C3-10 North 1280 . 0000
Str Type : --- East 625 . 0000
Str Cat : Stm Manhole Rim Elev 411 . 9200
Str Diam : 72 . 00 in Bottom El : 401 . 3200
Cont Area: B7 Hgrade El: 403 . 8200 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 305 Exit: 0 . 609 App Vel : 0 . 362 Junct: 0 . 079 Bend: 0 . 471
Reach <Invert> <Diam> < n > <End>
p6 401 . 320 30 . 00 0 . 012 Upper
p5 401 . 830 18 . 00 0 . 012 Lower
p12 401 . 420 30 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh7
Location : Node 14 , C2-7 North 1520 . 0000
Str Type : --- East 630 . 0000
Str Cat : Stm Manhole Rim Elev 404 . 8100
Str Diam : 60 . 00 in Bottom El: 397 . 7600
Cont Area: B5 Hgrade El: 400 . 8450 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 387 Exit: 0 . 773 App Vel: 0 . 609 Junct: 0 . 061 Bend: 0 . 009
Reach <Invert> <Diam> < n > <End>
p7 397 . 760 30 . 00 0 . 012 Upper
p6 397 . 860 30 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh8
Location : Node 14 , C2-4 North 1640 . 0000
Str Type : --- East 640 . 0000
Str Cat : Stm Manhole Rim Elev 399 . 8200
Str Diam : 60 . 00 in Bottom El: 394 . 5400
Cont Area: B3 Hgrade El: 395 . 1786 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 257 Exit: 0 . 515 App Vel: 0 . 773 Junct: 0 . 105 Bend: 0 . 009
Reach <Invert> <Diam> < n > <End>
p8 394 . 540 36. 00 0 . 012 Upper
p7 394 . 640 30 . 00 0 . 012 Lower
1/ 7/96 Ch2M Hill - Bellevue , WA page 14
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mh9
Location : Node 9 , C8-18 North 1890 . 0000
Str Type : --- East 650 . 0000
Str Cat : Stm Manhole Rim Elev : 395 . 5800
Str Diam : 60 . 00 in Bottom El : 389 . 7200
Cont Area: B1 Hgrade El: 394 . 2763 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 284 Exit: 0 . 569 App Vel: 0 . 515 Junct: 0 . 022 Bend: 0 . 685
Reach <Invert> <Diam> < n > <End>
p9 389 . 720 36 . 00 0 . 012 Upper
p8 389 . 820 36 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mhA
Location : Node 14 . C4-1 North 580 . 0000
Str Type : East 1100 . 0000
Str Cat : Stm Manhole Rim Elev 410 . 7400
Str Diam : 60 . 00 in Bottom El : 404 . 8700
Cont Area: Hgrade El: 404 . 9700 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 082 Exit: 0 . 164 App Vel: 0 . 439 Junct: 0 . 189 Bend: 0 . 584
Reach <Invert> <Diam> < n > <End>
p2 404 . 970 18 . 00 0 . 012 Lower
p3 405 . 000 24 . 00 0 . 012 Lower
p10 404 . 870 30 . 00 0 . 012 Upper
EXISTING STRUCTURE REACH ID No. mhB
Location : Node 14 .C3-1 North 860 . 0000
Str Type : East 1125 . 0000
Str Cat : Stm Manhole Rim Elev 409 . 2900
Str Diam : 72 . 00 in Bottom El: 404 . 0000
Cont Area: B10 Hgrade El: 407 . 9036 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 138 Exit: 0 . 276 App Vel: 0 . 164 Junct: 0 . 036 Bend: 0 . 001
Reach <Invert> <Diam> < n > <End>
p10 404 . 310 30 . 00 0 . 012 Lower
p11 404 . 000 30 . 00 0 . 012 Upper
1/ 7/96 Ch2M Hill - Bellevue, WA page 15
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
---------------------------------------------------------------------
---------------------------------------------------------------------
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mhC
Location : North 1260 . 0000
Str Type : East 1150 . 0000
Str Cat : Stm Manhole Rim Elev 416 . 0800
Str Diam : 72 . 00 in Bottom El: 403 . 1000
Cont Area: B7 Hgrade El: 406 . 7511 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 181 Exit: 0 . 362 App Vel: 0 . 276 Junct: 0 . 031 Bend: 0 . 368
Reach <Invert> <Diam> < n > <End>
p12 403 . 100 30 . 00 0 . 012 Upper
pll 403 . 200 30 . 00 0 . 012 Lower
Results
• Hydrograph Summary
• History of Hydrograph Activity
1/ 7/96 Ch2M Hill - Bellevue, WA page 5
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min. cf\AcFt Acres
1 16 . 701 480 261441 c f 60 . 83 2-Year Design Storm
2 28 . 856 480 439181 c f 60 . 83 10-Year Design Storm
3 35 . 789 480 541432 c f 60 . 83 25-Year Design Storm
4 42 . 776 480 645206 c f 60 . 83 100-Year Design Storm
3/ 4/96 Ch2M Hill - Bellevue, WA page 1
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
HISTORY OF HYDROGRAPH ACTIVITY
Date of Session: 1/ 8/96
CLEARHIS
ZERO 1 20
REMARK xxxxxxxxxx*x*********************x***********x*xx***x*xxxxxxxxxxxxx
START OUT BY ROUTING THE 2 YEAR STORM THROUGH HYDROGRAPH 1
LSTEND *xx*xxx************************************x**xx**x*xxxxxxxxxxxxxxx
CHANGE "2 YR STORM" 2.00 PRECIP
BO B1 B10 B12 B14 B15
B3 B5 B6 B7 B9
LSTEND
ROUTE HYDROGRAPH 1 THROUGH REACH n1
Network n3
Reach <AREA> <Act Q> <Q FUII> % Full Ndepth <Diam> <NVeI> <FVeI> Carea
p3 9.31 2.64 21.52 12.29 18.11 24.00 4.42 6.37 B14
Network n2
Reach <AREA> <Act Q> <Q Full> % Full Ndepth <Diam> <NVeI> <FVeL> Carea
p5 5.44 1.54 7.71 20.02 12.33 18.00 3.24 4.06 B9
Network n1
Reach <AREA> <Act Q> <Q Full> % Full Ndepth <Diam> <NVeI> <FVeI> Carea
p1 12.78 1.93 7.44 25.91 4.33 12.00 7.54 8.80 B12
p2 17.74 3.00 12.27 24.45 11.70 18.00 5.44 6.45 B15
p10 27.05 5.42 21.39 25.35 19.29 30.00 3.45 4.05
p11 33.53 7.21 21.41 33.68 17.51 30.00 3.73 4.06 B10
p12 37.53 8.34 27.10 30.77 18.12 30.00 4.61 5.13 B7
p6 46.97 11.01 57.54 19.14 9.24 30.00 8.58 10.90 B7
p7 51.54 12.86 77.15 16.67 8.60 30.00 11.06 14.61 B5
p8 58.44 15.75 107.04 14.72 9.68 36.00 10.28 14.08 B3
p9 60.83 16.70 90.37 18.48 10.88 36.00 9.26 11.88 B1
p13 60.83 16.70 48.56 34.39 20.84 36.00 5.91 6.39
HGRADE hgradel
n1
n2
n3
SUBMERGED 389.08
LSTEND
HGLINE hgradel
3/ 4/96 Ch2M Hill - Bellevue, WA page 2
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
HISTORY OF HYDROGRAPH ACTIVITY
Hydraulic Gradeline for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent-HGL EntLoss ExtLoss OutLet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
junction 389.08
mh10 junction 16.70 0.79 388.93 0.04 0.09 389.06 389.08 0.09 0.12 0.00 389.11 394.85
mh9 mh10 16.70 6.42 tw & do <dc: Inlet CtrL Assumed 390.37 0.08 0.10 0.00 390.40 395.58
mh8 mh9 15.75 17.45 tw & do <dc: Inlet Ctrl Assumed 395.17 0.11 0.00 0.02 395.08 399.82
mh7 mh8 12.86 21.95 tw & do <dc: Inlet CtrL Assumed 398.34 0.08 0.00 0.01 398.28 404.81
mh6 mh7 11.01 40.19 tw & do <dc: Inlet CtrL Assumed 401.87 0.04 0.06 0.01 401.90 411.92
mhC mh6 8.34 29.14 404.00 0.02 0.04 404.07 403.60 0.03 0.04 0.00 404.09 416.08
mhB mhC 7.21 1.45 405.05 0.02 0.03 405.10 404.48 0.02 0.00 0.00 405.09 409.29
mhA mhB 5.42 0.93 406.02 0.01 0.02 406.05 405.29 0.04 0.06 0.02 406.09 410.74
mh2 mhA 3.00 0.19 407.61 0.02 0.04 407.68 407.50 0.09 0.00 0.03 407.62 412.47
mh1 mh2 1.93 20.69 tw & do <dc: Inlet CtrL Assumed 426.41 0.00 0.00 0.00 426.41 437.82
mh6 402.86
mh5 mh6 1.54 0.11 403.88 0.01 0.01 403.90 403.70 0.00 0.00 0.00 403.90 413.58
mhA 406.51
mh3 mhA 2.64 0.03 407.04 0.01 0.01 407.06 406.87 0.00 0.00 0.00 407.06 409.88
REMARK
ROUTING THE 10 YEAR STORM THROUGH HYDROGRAPH 2
LSTEND
CHANGE "10 YR STORM" 2.90 PRECIP
BO B1 B10 B12 B14 B15
B3 B5 B6 B7 69
LSTEND
ROUTE HYDROGRAPH 2 THROUGH REACH n1
Network n3
Reach <AREA> <Act Q> <Q Full> % Full Ndepth <Diam> <NVeL> <FVeI> Carea
p3 9.31 4.75 21.52 22.09 16.04 24.00 5.22 6.37 B14
Network n2
Reach <AREA> <Act Q> <Q Full> % Full Ndepth <Diam> <NVeL> <FVeI> Carea
p5 5.44 2.73 7.71 35.39 10.30 18.00 3.78 4.06 B9
Network n1
Reach <AREA> <Act Q> <Q FULL> % Full Ndepth <Diam> <NVeL> <FVeI> Carea
p1 12.78 3.95 7.44 53.17 5.50 12.00 9.10 8.80 B12
p2 17.74 5.91 12.27 48.19 9.19 18.00 6.51 6.45 B15
p10 27.05 10.26 21.39 47.97 15.28 30.00 4.08 4.05
3/ 4/96 Ch2M Hill - Bellevue , WA page 3
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
HISTORY OF HYDROGRAPH ACTIVITY
p11 33.53 13.43 21.41 62.71 18.05 30.00 4.35 4.06 B10
p12 37.53 15.42 27.10 56.90 16.96 30.00 5.39 5.13 B7
p6 46.97 20.14 57.54 35.01 12.76 30.00 10.13 10.90 B7
p7 51.54 22.97 77.15 29.77 11.67 30.00 13.00 14.61 B5
p8 58.44 27.37 107.04 25.57 12.91 36.00 12.02 14.08 B3
p9 60.83 28.86 90.37 31.93 14.55 36.00 10.78 11.88 B1
p13 60.83 28.86 48.56 59.42 20.92 36.00 6.77 6.39
HGRADE hgradel
n1
n2
n3
SUBMERGED 389.58
LSTEND
HGLINE hgradel
Hydraulic Gradeline for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent-HGL EntLoss ExtLoss OutLet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
junction 389.58
mh10 junction 28.86 0.54 390.14 0.13 0.26 390.53 389.33 0.26 0.34 0.00 390.62 394.85
mh9 mh10 28.86 0.20 390.20 0.13 0.26 390.59 390.63 0.23 0.31 0.01 390.71 395.58
mh8 mh9 27.37 9.60 tw & do <dc: Inlet CtrL Assumed 395.40 0.34 0.00 0.05 395.12 399.82
mh7 mh8 22.97 51.19 tw & do <dc: Inlet CtrL Assumed 398.67 0.26 0.00 0.03 398.44 404.81
mh6 mh7 20.14 35.08 tw & do <dc: Inlet CtrL Assumed 402.14 0.15 0.20 0.03 402.22 411.92
mhC mh6 15.42 12.98 404.52 0.08 0.15 404.75 403.78 0.12 0.15 0.01 404.80 416.08
mhB mhC 13.43 0.67 405.49 0.06 0.12 405.67 404.63 0.07 0.00 0.02 405.62 409.29
mhA mhB 10.26 0.51 406.14 0.03 0.07 406.24 405.42 0.17 0.23 0.08 406.38 410.74
mh2 mhA 5.91 0.51 407.81 0.09 0.17 408.07 407.69 0.39 0.00 0.13 407.81 412.4T
mh1 mh2 3.95 18.82 tw & do <dc: Inlet CtrL Assumed 427.77 0.00 0.00 0.00 427.77 437.82
mh6 402.69
mh5 mh6 2.T3 0.60 404.02 0.02 0.04 404.08 403.77 0.00 0.00 0.00 404.08 413.58
mhA 406.38
mh3 mhA 4.75 0.13 407.15 0.02 0.04 407.20 406.96 0.00 0.00 0.00 407.20 409.88
REMARK
ROUTING THE 25 YEAR STORM THROUGH HYDROGRAPH 3
LSTEND
CHANGE "25 YR STORM" 3.40 PRECIP
BO B1 B10 B12 B14 B15
B3 B5 B6 B7 B9
LSTEND
ROUTE HYDROGRAPH 3 THROUGH REACH n1
Network n3
Reach <AREA> <Act Q> <Q FULL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
3/ 4/96 Ch2M Hill - Bellevue, WA page 4
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
HISTORY OF HYDROGRAPH ACTIVITY
p3 9.31 5.97 21.52 27.72 15.02 24.00 5.56 6.37 B14
Network n2
Reach <AREA> <Act Q> <Q FULL> % Full Ndepth <Diam> <NVeI> <FVeI> Carea
p5 5.44 3.40 7.71 44.13 9.27 18.00 4.01 4.06 B9
Network n1
Reach <AREA> <Act Q> <Q FuLL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p1 12.78 5.17 7.44 69.48 4.26 12.00 9.66 8.80 B12
p2 17.74 7.63 12.27 62.23 10.77 18.00 6.91 6.45 B15
p10 27.05 13.09 21.39 61.18 17.76 30.00 4.32 4.05
p11 33.53 17.04 21.41 79.57 21.36 30.00 4.56 4.06 B10
p12 37.53 19.53 27.10 72.04 19.84 30.00 5.67 5.13 B7
p6 46.97 25.42 57.54 44.17 14.56 30.00 10.76 10.90 B7
p7 51.54 28.77 77.15 37.29 13.22 30.00 13.81 14.61 B5
p8 58.44 34.01 107.04 31.77 14.51 36.00 12.75 14.08 B3
p9 60.83 35.79 90.37 39.60 16.41 36.00 11.41 11.88 B1
p13 60.83 35.79 48.56 73.70 24.20 36.00 7.08 6.39
HGRADE hgradel
n1
n2
n3
SUBMERGED 391.08
LSTEND
HGLINE hgradel
Hydraulic Gradeline for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent_HGL EntLoss ExtLoss OutLet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
junction 391.08
mh10 junction 35.79 0.21 391.29 0.20 0.40 391.88 389.52 0.40 0.53 0.00 392.02 394.85
mh9 mh10 35.79 0.22 392.24 0.20 0.40 392.83 390.82 0.36 0.48 0.02 392.97 395.58
mh8 mh9 34.01 0.55 393.52 0.18 0.36 394.06 395.58 0.53 0.01 0.07 395.12 399.82
mh7 mh8 28.77 75.34 tw & do <dc: Inlet CtrL Assumed 399.77 0.42 0.01 0.04 399.40 404.81
mh6 mh7 25.42 1.60 tw & do <dc: Inlet CtrL Assumed 402.35 0.25 0.32 0.05 402.48 411.92
mhC mh6 19.53 7.28 404.75 0.12 0.25 405.12 403.91 0.19 0.25 0.02 405.20 416.08
mhB mhC 17.04 0.61 405.84 0.09 0.19 406.12 404.73 0.11 0.00 0.02 406.03 409.29
mhA mhB 13.09 0.36 406.39 0.06 0.11 406.56 405.49 0.29 0.39 0.13 406.78 410.74
mh2 mhA 7.63 0.99 407.77 0.14 0.29 408.20 407.91 0.67 0.01 0.22 407.75 412.47
mh1 mh2 5.17 47.70 tw & do <dc: Inlet CtrL Assumed 428.49 0.00 0.00 0.00 428.49 437.82
mh6 402.60
mh5 mh6 3.40 1.32 404.15 0.03 0.06 404.23 403.81 0.00 0.00 0.00 404.23 413.58
Input Data
• Basin Summary
• Reach Summary
• Structure Report
1/ 7/96 Ch2M Hill - Bellevue , WA page 1
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
BASIN SUMMARY
BASIN ID: BO NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 0 . 38 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 30 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 81 . 00
TIME OF CONC. . . . . : 68 . 07 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 0 . 08 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 220 . 00 ns : 0 . 4000 p2yr: 2 . 00 s : 0 . 0250
TcReach - Sheet L: 80 . 00 ns : 0 . 4100 p2yr: 2 . 00 s : 0 . 0250
TcReach - Shallow L: 20 . 00 ks : 11 . 00 s : 0 . 0250
PEAK RATE: 0 . 14 cfs VOL: 0 . 07 Ac-ft TIME: 500 min
BASIN ID: B1 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 2 . 39 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 48 Acres
TIME INTERVAL. . . . . 10 . 00 min CN. . . . . 86 . 00
TIME OF CONC. . . . . : 23 . 38 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 1 . 91 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 100 . 00 ns: 0 . 4000 p2yr: 2 . 00 s : 0 . 0400
TcReach - Sheet L: 200 . 00 ns : 0 . 0110 p2yr: 2 . 00 s : 0 . 0400
TcReach - Shallow L: 250 . 00 ks : 27 . 00 s : 0 . 0400
PEAK RATE: 2 . 08 cfs VOL: 0 . 67 Ac-ft TIME: 480 min
BASIN ID: B10 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 6 . 48 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 3 . 76 Acres
TIME INTERVAL. . . . . 10 . 00 min CN. . . . . 86 . 00
TIME OF CONC. . . . . : 25 . 88 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 2. 72 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 200 . 00 ns: 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Sheet L: 100 . 00 ns : 0 . 0110 p2yr: 2 . 00 s : 0 . 0200
TcReach - Shallow L: 230 . 00 ks : 27 . 00 s : 0 . 0200
TcReach - Channel L: 80 . 00 kc:42 . 00 s : 0 . 0030
TcReach - Channel L: 250 . 00 kc : 42 . 00 s : 0 . 0070
PEAK RATE: 4 . 74 cfs VOL: 1 . 57 Ac-ft TIME: 480 min
1/ 7/96 Ch2M Hill - Bellevue, WA page 2
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
BASIN SUMMARY
BASIN ID: B12 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 12 . 78 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 10 . 86 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 84 . 20
TIME OF CONC. . . . . : 41 . 20 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 1 . 92 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 300 . 00 ns : 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Shallow L: 125 . 00 ks : 11 . 00 s : 0 . 0200
TcReach - Shallow L: 545 . 00 ks : 5 . 00 s : 0 . 0350
TcReach - Shallow L: 70 . 00 ks : 27 . 00 s : 0 . 0200
PEAK RATE: 6 . 42 cfs VOL: 2 . 62 Ac-ft TIME: 490 min
BASIN ID: B14 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 9 . 31 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 5 . 68 Acres
TIME INTERVAL. . . . . 10 . 00 min CN. . . . . 86 . 00
TIME OF CONC. . . . . : 17 . 07 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 3 . 63 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 130 . 00 ns : 0 . 1500 p2yr: 2 . 00 s : 0. 0200
TcReach - Sheet L: 30 . 00 ns : 0 . 0110 p2yr: 2 . 00 s : 0 . 0200
TcReach - Channel L: 165 . 00 kc : 42. 00 s : 0 . 0030
PEAK RATE: 7 . 19 cfs VOL: 2. 22 Ac-ft TIME: 470 min
BASIN ID: B15 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 4 . 96 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 3 . 57 Acres
TIME INTERVAL. . . . : 10. 00 min CN. . . . : 86 . 60
TIME OF CONC. . . . . : 36. 09 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 1 . 39 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 300 . 00 ns : 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Shallow L: 300 . 00 ks : 11 . 00 s: 0 . 0200
TcReach - Shallow L: 100 . 00 ks : 27 . 00 s: 0 . 0200
TcReach - Shallow L: 70 . 00 ks : 27 . 00 s : 0 . 0200
TcReach - Channel L: 330 . 00 kc : 17 . 00 s : 0 . 0200
PEAK RATE: 2. 98 cfs VOL: 1 . 15 Ac-ft TIME: 490 min
1/ 7/96 Ch2M Hill - Bellevue, WA page 3
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
BASIN SUMMARY
BASIN ID: B3 NAME: 100 YR PRECIP
TOTAL AREA. . .. . . . : 6 . 90 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 95 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 88 . 00
TIME OF CONC . . . . . : 15 . 76 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 5 . 95 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 100 . 00 ns: 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Sheet L: 200 . 00 ns: 0 . 0110 p2yr: 2 . 00 s : 0 . 0200
TcReach - Shallow L: 400 . 00 ks : 67 . 20 s : 0 . 0200
PEAK RATE: 6 . 69 cfs VOL: 2 . 00 Ac-ft TIME: 470 min
BASIN ID: B5 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 4 . 57 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 57 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 60
TIME OF CONC. . . . . : 14 . 03 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 4 . 00 Acres
CN. . . . . 98 . 00
PEAK RATE: 4 . 66 cfs VOL: 1 . 33 Ac-ft TIME: 470 min
BASIN ID: B6 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 6 . 13 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 3 . 56 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 21 . 03 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 2 . 57 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 150 . 00 ns: 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Sheet L: 150 . 00 ns : 0 . 0110 p2yr: 2. 00 s : 0 . 0200
TcReach - Shallow -L: 60 . 00 ks : 27 . 00 s : 0 . 0200
TcReach - Channel L: 380 . 00 kc : 42. 00 s: 0 . 0100
PEAK RATE: 4 . 71 cfs VOL: 1 . 48 Ac-ft TIME: 480 min
1/ 7/96 Ch2M Hill - Bellevue , WA page 4
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
BASIN SUMMARY
BASIN ID: B7 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 4 . 00 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 2 . 32 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 24 . 87 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 1 . 68 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 200 . 00 ns : 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Sheet L: 100 . 00 ns : 0 . 0110 p2yr: 2 . 00 s : 0 . 0200
TcReach - Shallow L: 150 . 00 ks : 27 . 00 s : 0 . 0200
TcReach - Channel L: 224 . 00 kc : 42 . 00 s : 0 . 0065
PEAK RATE: 2 . 98 cfs VOL: 0 . 97 Ac-ft TIME: 480 min
BASIN ID: B9 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 5 . 44 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 3 . 16 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 24 . 12 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 2 . 28 Acres
CN. . . . . 98 . 00
PEAK RATE: 4 . 08 cfs VOL: 1 . 31 Ac-ft TIME: 480 min
3/ 4/96 Ch2M Hill - Bellevue, WA page 5
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
---------------------------------------------------------------------
---------------------------------------------------------------------
HISTORY OF HYDROGRAPH ACTIVITY
mhA 406.78
mh3 mhA 5.97 0.12 407.28 0.03 0.06 407.36 407.00 0.00 0.00 0.00 407.36 409.88
REMARK
ROUTING THE 100 YEAR STORM THROUGH HYDROGRAPH 4
LSTEND
CHANGE "100 YR PRECIP" 3.90 PRECIP
BO B1 B10 B12 B14 B15
B3 B5 86 B7 B9
LSTEND
ROUTE HYDROGRAPH 4 THROUGH REACH n1
Network n3
Reach <AREA> <Act Q> <Q FuLL> % FuLL Ndepth <Diam> <NVeL> <FVeL> Carea
p3 9.31 7.19 21.52 33.39 14.06 24.00 5.84 6.37 B14
Network n2
Reach (AREA) <Act Q> (Q FuLL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p5 5.44 4.08 7.71 52.92 9.73 18.00 4.19 4.06 B9
Network n1
Reach <AREA> <Act Q> <Q FuLL> % FuLL Ndepth <Diam> <NVeL> <FVeL> Carea
p1 12.78 6.42 7.44 86.25 2.86 12.00 10.00 8.80 B12
p2 17.74 9.40 12.27 76.60 12.45 18.00 7.21 6.45 B15
p10 27.05 15.96 21.39 74.62 20.35 30.00 4.50 4.05
p11 33.53 20.70 21.41 96.69 25.83 30.00 4.60 4.06 B10
p12 37.53 23.68 27.10 87.39 23.12 30.00 5.84 5.13 B7
p6 46.97 30.75 57.54 53.44 13.69 30.00 11.28 10.90 B7
p7 51.54 34.63 77.15 44.89 14.70 30.00 14.48 14.61 B5
p8 58.44 40.70 107.04 38.02 16.03 36.00 13.37 14.08 83
p9 60.83 42.78 90.37 47.34 17.81 36.00 11.94 11.88 B1
p13 60.83 42.78 48.56 88.09 27.94 36.00 7.27 6.39
HGRADE hgradel
n1
n2
n3
SUBMERGED 391.58
LSTEND
HGLINE hgradel
Hydraulic Gradeline for Reach hgradel
3/ 4/96 Ch2M Hill - Bellevue, WA page 6
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
---------------------------------------------------------------------
---------------------------------------------------------------------
HISTORY OF HYDROGRAPH ACTIVITY
<-FROM-> <--TO--> <FLOW> floss Ent_HGL EntLoss ExtLoss OutLet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
junction 391.58
mh10 junction 42.78 0.30 391.88 0.28 0.57 392.73 389.75 0.57 0.76 0.00 392.92 394.85
mh9 mh10 42.78 0.31 393.23 0.28 0.57 394.08 391.05 0.51 0.69 0.02 394.28 395.58
mh8 mh9 40.70 0.79 395.07 0.26 0.51 395.84 395.79 0.77 0.01 0.10 395.18 399.82
mh7 mh8 34.63 70.29 tw & do <dc: Inlet CtrL Assumed 401.38 0.61 0.01 0.06 400.85 404.81
mh6 mh7 30.75 1.14 401.99 0.30 0.61 402.90 404.41 0.36 0.47 0.08 404.60 411.92
mhC mh6 23.68 1.48 406.09 0.18 0.36 406.63 404.07 0.28 0.37 0.03 406.75 416.08
mhB mhC 20.70 0.87 407.62 0.14 0.28 408.03 404.85 0.16 0.00 0.04 407.90 409.29
mhA mhB 15.96 0.36 408.26 0.08 0.16 408.51 405.57 0.44 0.58 0.19 408.85 410.74
mh2 mhA 9.40 1.49 410.34 0.22 0.44 411.00 409.29 1.04 0.01 0.33 410.30 412.47
mh1 mh2 6.42 16.22 426.52 0.52 1.04 428.07 429.42 0.00 0.00 0.00 429.42 437.82
mh6 404.60
mh5 mh6 4.08 0.52 405.13 0.04 0.08 405.25 403.84 0.00 0.00 0.00 405.25 413.58
mhA 408.85
mh3 mhA 7.19 0.20 409.05 0.04 0.08 409.17 407.04 0.00 0.00 0.00 409.17 409.88
End program file BASIN_O.PGM
Date of Session: 3/ 4/96
1/ 7/96 Ch2M Hill - Bellevue, WA page 7
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
---------------------------------------------------------------------
---------------------------------------------------------------------
REACH SUMMARY
PIPE REACH ID No. pl
From: mhl To: mh2
Pipe Diameter: 1 . 00 ft n: 0 . 0120
Pipe Length 590 . 17 ft s : 0 . 0319
Up invert 426. 11 ft down invert: 407 . 27
Collection Area: 12. 78 Ac .
Design Flow 6 . 42 cfs Dsgn Depth: 0 . 24 ft
Pipe Capacity 7 . 44 cfs
Design Vel 10 . 00 fps Travel Time: 0 . 98 min
Pipe Full Vel 9 . 72 fps
1/ 7/96 Ch2M Hill - Bellevue , WA page 8
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
REACH SUMMARY
PIPE REACH ID No. p10
From: mhA To: mhB
Pipe Diameter: 2 . 50 ft n: 0 . 0120
Pipe Length 281 . 11 ft s : 0 . 0020
Up invert 404 . 87 ft down invert: 404 . 31
Collection Area: 27 . 05 Ac .
Design Flow 15 . 96 cfs Dsgn Depth: 1 . 70 ft
Pipe Capacity 21 . 39 cfs
Design Vel 4 . 50 fps Travel Time : 1 . 04 min
Pipe Full Vel 4 . 47 fps
PIPE REACH ID No. pll
From: mhB To: mhC
Pipe Diameter: 2 . 50 ft n: 0 . 0120
Pipe Length 400 . 78 ft s : 0 . 0020
Up invert 404 . 00 ft down invert: 403 . 20
Collection Area: 33 . 53 Ac .
Design Flow 20 . 70 cfs Dsgn Depth: 2 . 15 ft
Pipe Capacity 21 . 41 cfs
Design Vel 4 . 60 fps Travel Time : 1 . 45 min
Pipe Full Vel 4 . 48 fps
PIPE REACH ID No. p12
From: mhC To: mh6
Pipe Diameter: 2 . 50 ft n: 0 . 0120
Pipe Length 525 . 38 ft s : 0 . 0032
Up invert 403 . 10 ft down invert: 401 . 42
Collection Area: 37 . 53 Ac .
Design Flow 23 . 68 cfs Dsgn Depth: 1. 93 ft
Pipe Capacity 27 . 10 cfs
Design Vel 5 . 84 fps Travel Time : 1. 50 min
Pipe Full Vel 5 . 67 fps
PIPE REACH ID No. p13
From: mh10 To: junction
Pipe Diameter: 3 . 00 ft n: 0 . 0120
Pipe Length 85 . 00 ft s: 0 . 0039
Up invert 388 . 41 ft down invert: 388 . 08
Collection Area: 60 . 83 Ac .
Design Flow 42 . 78 cfs Dsgn Depth: 2. 33 ft
Pipe Capacity 48 . 56 cfs
Design Vel 7 . 27 fps Travel Time : 0 . 19 min
Pipe Full Vel 7 . 05 fps
1/ 7/96 Ch2M Hill - Bellevue, WA page 9
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 1B - Bypass
---------------------------------------------------------------------
---------------------------------------------------------------------
REACH SUMMARY
PIPE REACH ID No. p2
From: mh2 To: mhA
Pipe Diameter: 1 . 50 ft n: 0 . 0120
Pipe Length 220 . 27 ft s : 0 . 0100
Up invert 407 . 17 ft down invert: 404 . 97
Collection Area: 17 . 74 Ac .
Design Flow 9 . 40 cfs Dsgn Depth: 1 . 04 ft
Pipe Capacity 12 . 27 cfs
Design Vel 7 . 21 fps Travel Time: 0 . 51 min
Pipe Full Vel 7 . 12 fps
PIPE REACH ID No. p3
From: mh3 To: mhA
Pipe Diameter: 2 . 00 ft n: 0 . 0120
Pipe Length 235 . 36 ft s : 0 . 0066
Up invert 406 . 56 ft down invert: 405 . 00
Collection Area: 9 . 31 Ac .
Design Flow 7 . 19 cfs Dsgn Depth: 1 . 17 ft
Pipe Capacity 21 . 52 cfs
Design Vel 5 . 84 fps Travel Time: 0 . 67 min
Pipe Full Vel 7 . 03 fps
PIPE REACH ID No. p5
From: mh5 To: mh6
Pipe Diameter: 1 . 50 ft n: 0 . 0120
Pipe Length 410 . 12 ft s : 0 . 0040
Up invert 403 .45 ft down invert: 401 . 83
Collection Area: 5 . 44 Ac.
Design Flow 4 . 08 cfs Dsgn Depth: 0 . 81 ft
Pipe Capacity 7 . 71 cfs
Design Vel 4 . 19 fps Travel Time: 1 . 63 min
Pipe Full Vel 4 . 48 fps
PIPE REACH ID No. p6
From: mh6 To: mh7
Pipe Diameter: 2 . 50 ft n: 0 . 0120
Pipe Length 240 . 05 ft s : 0 . 0144
Up invert 401. 32 ft down invert: 397 . 86
Collection Area: 46 . 97 Ac .
Design Flow 30 . 75 cfs Dsgn Depth: 1 . 14 ft
Pipe Capacity 57 . 54 cfs
Design Vel 11 . 28 fps Travel Time: 0 . 35 min
Pipe Full Vel 12 . 03 fps
Hydrologic/Hydraulic ModeNing Input Data and Results
Alternative 3A, Diversion: NE 10th Street 1 North to Existing
Creek and Arches
Input Data
• Basin Summary
• Reach Summary
• Structure Report
1/ 8/96 Ch2M Hill - Bellevue , WA page 1
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
BASIN SUMMARY
BASIN ID: BO NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 0 . 38 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 30 Acres
TIME INTERVAL. . . . . 10 . 00 min CN. . . . . 81 . 00
TIME OF CONC. . . . . : 68 . 07 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 0 . 08 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 220 . 00 ns : 0 . 4000 p2yr: 2 . 00 s : 0 . 0250
TcReach - Sheet L: 80 . 00 ns : 0 . 4100 p2yr: 2 . 00 s : 0 . 0250
TcReach - Shallow L: 20 . 00 ks : 11. 00 s : 0 . 0250
PEAK RATE: 0 . 14 cfs VOL: 0 . 07 Ac-ft TIME: 500 min
BASIN ID: B1 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 2 . 39 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 48 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 23 . 38 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 1 . 91 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 100 . 00 ns: 0 . 4000 p2yr: 2 . 00 s: 0 . 0400
TcReach - Sheet L: 200 . 00 ns : 0 . 0110 p2yr: 2 . 00 s : 0 . 0400
TcReach - Shallow L: 250 . 00 ks : 27 . 00 s : 0 . 0400
PEAK RATE: 2 . 08 cfs VOL: 0 . 67 Ac-ft TIME: 480 min
BASIN ID: B10 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 6. 48 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 3 . 76 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 25 . 88 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 2. 72 Acres
CN. . . . . 98. 00
TcReach - Sheet L: 200 . 00 ns : 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Sheet L: 100 . 00 ns : 0 . 0110 p2yr: 2. 00 s: 0 . 0200
TcReach - Shallow L: 230 . 00 ks : 27 . 00 s: 0 . 0200
TcReach - Channel L: 80 . 00 kc : 42. 00 s : 0 . 0030
TcReach - Channel L: 250 . 00 kc :42. 00 s: 0 . 0070
PEAK RATE: 4 . 74 cfs VOL: 1 . 57 Ac-ft TIME: 480 min
1/ 8/96 Ch2M Hill - Bellevue , WA page 2
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
---------------------------------------------------------------------
---------------------------------------------------------------------
BASIN SUMMARY
BASIN ID: B12 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 12 . 78 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 10 . 86 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 84 . 20
TIME OF CONC. . . . . : 41 . 20 min IMPERVIOUS AREA
ABSTRACTION COEFF : 0 . 20 AREA. . : 1 . 92 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 300 . 00 ns : 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Shallow L: 125 . 00 ks : 11 . 00 s : 0 . 0200
TcReach - Shallow L: 545 . 00 ks : 5 . 00 s: 0 . 0350
TcReach - Shallow L: 70 . 00 ks : 27 . 00 s : 0 . 0200
PEAK RATE: 6 .42 cfs VOL: 2 . 62 Ac-ft TIME: 490 min
BASIN ID: B14 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 9 . 31 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 5 . 68 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 17 . 07 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 3 . 63 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 130 . 00 ns : 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Sheet L: 30 . 00 ns : 0 . 0110 p2yr: 2 . 00 s: 0 . 0200
TcReach - Channel L: 165 . 00 kc : 42 . 00 s : 0 . 0030
PEAK RATE: 7 . 19 cfs VOL: 12. 22 Ac-ft TIME: 470 min
BASIN ID: B15 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 9 . 51 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 7 . 21 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 85 . 80
TIME OF CONC. . . . . : 36 . 09 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 2 . 30 Acres
CN. . . . . 98. 60
TcReach - Sheet L: 300 . 00 ns : 0 . 1500 p2yr: 2 . 00 s: 0 . 0200
TcReach - Shallow L: 300 . 00 ks : 11 . 00 s : 0 . 0200
TcReach - Shallow L: 100 . 00 ks: 27 . 00 s : 0 . 0200
TcReach - Shallow L: 70 . 00 ks : 27 . 00 s : 0 . 0200
TcReach - Channel L: 330 . 00 kc: 17 . 00 s : 0 . 0200
PEAK RATE: 5 . 52 cfs VOL: 2 . 14 Ac-ft TIME: 490 min
1/ 8/96 Ch2M Hill - Bellevue, WA page 3
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
BASIN SUMMARY
BASIN ID: B3 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 6 . 90 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 95 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 88 . 00
TIME OF CONC. . . . . : 15 . 76 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 5 . 95 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 100 . 00 ns : 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Sheet L: 200 . 00 ns : 0 . 0110 p2yr: 2. 00 s : 0 . 0200
TcReach - Shallow L: 400 . 00 ks : 67 . 20 s : 0 . 0200
PEAK RATE: 6 . 69 cfs VOL: 2 . 00 Ac-ft TIME: 470 min
BASIN ID: B5 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 4 . 57 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 0 . 57 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86. 60
TIME OF CONC. . . . . : 14 . 03 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 4 . 00 Acres
CN. . . . . 98. 00
PEAK RATE: 4 . 66 cfs VOL: 1 . 33 Ac-ft TIME: 470 min
BASIN ID: B6 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 6 . 13 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 3 . 56 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86. 00
TIME OF CONC. . . . . : 21 . 03 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 2. 57 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 150 . 00 ns : 0 . 1500 p2yr: 2. 00 s: 0 . 0200
TcReach - Sheet L: 150 . 00 ns : 0 . 0110 p2yr: 2 . 00 s: 0 . 0200
TcReach - Shallow L: 60 . 00 ks : 27 . 00 s : 0 . 0200
TcReach - Channel L: 380 . 00 kc : 42 . 00 s: 0 . 0100
PEAK RATE: 4 . 71 cfs VOL: 1 . 48 Ac-ft TIME: 480 min
1/ 8/96 Ch2M Hill - Bellevue, WA page 4
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
BASIN SUMMARY
BASIN ID: B7 NAME: 100 YEAR PRECIP.
TOTAL AREA. . . . . . . : 4 . 00 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 2 . 32 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 24 . 87 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 1 . 68 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 200 . 00 ns: 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Sheet L: 100 . 00 ns: 0 . 0110 p2yr: 2 . 00 s : 0 . 0200
TcReach - Shallow L: 150 . 00 ks: 27 . 00 s : 0 . 0200
TcReach - Channel L: 224 . 00 kc :42 . 00 s : 0 . 0065
PEAK RATE: 2 . 98 cfs VOL: 0 . 97 Ac-ft TIME: 480 min
BASIN ID: B9 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 5 . 44 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 3 . 16 Acres
TIME INTERVAL. . . . : 10 . 00 min CN. . . . : 86 . 00
TIME OF CONC. . . . . : 24 . 12 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 2. 28 Acres
CN. . . . . 98 . 00
PEAK RATE: 4 . 08 cfs VOL: 1 . 31 Ac-ft TIME: 480 min
1/ 8/96 Ch2M Hill - Bellevue , WA page 6
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
-----------------
LEVEL POOL TABLE SUMMARY
MATCH INFLOW -STO- -DIS- <-PEAK- STORAGE
<--------DESCRIPTION------- cfs) (cfs) --id- --i - - TAGE> id VOL (cf)
ROUTING POND ................. 3. .28 POND 5.18 1 30859.64 Cf
See HEC-1 Results
1/ 8/96 Ch2M Hill - Bellevue, WA page 4
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
REACH SUMMARY
PIPE REACH ID No. pl
From: mhl To: mh2
Pipe Diameter: 1.00 ft n: 0.0120
Pipe Length 590.19 ft s: 0 .0319
Up invert 426.11 ft down invert: 407.27
Collection Area: 12.78 Ac.
Design Flow 5.17 cfs Dsgn Depth: 0. 36 ft
Pipe Capacity 7.44 cfs
Design Vel 9.66 fps Travel Time: 1.02 min
Pipe Full Vel 9.72 fps
PIPE REACH ID No. p10
From: mhA To: mhB
Pipe Diameter: 2.50 ft n: 0.0120
Pipe Length 281.11 ft s: 0.0020
Up invert 404 .87 ft down invert: 404. 31
Collection Area: 27.05 Ac.
Design Flow 15.96 cfs Dsgn Depth: 1.70 ft
Pipe Capacity 21.39 cfs
Design Vel 4.50 fps Travel Time: 1.04 min
Pipe Full Vel 4.47 fps
PIPE REACH ID No. pll
From: mhB To: mhC
Pipe Diameter: 2.00 ft n: 0.0120
Pipe Length 385.81 ft s: 0.0016
Up invert 403.11 ft down invert: 402 .50
Collection Area: 6.48 Ac.
Design Flow 4.74 cfs Dsgn Depth: 1.02 ft
Pipe Capacity 10.51 cfs
Design Vel 3.09 fps Travel Time: 2.08 min
Pipe Full Vel 3.43 fps
1/ 8/96 Ch2M Hill - Bellevue, WA page 5
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
REACH SUMMARY
PIPE REACH ID No. p12
From: mhC To: mh6
Pipe Diameter: 2.00 ft n: 0.0120
Pipe Length 525. 38 ft s: 0.0015
Up invert 402. 45 ft down invert: 401. 66
Collection Area: 10 .48 Ac.
Design Flow 7.72 cfs Dsgn Depth: 1 . 37 ft
Pipe Capacity 10.25 cfs
Design Vel 3 . 38 fps Travel Time: 2 .59 min
Pipe Full Vel 3 . 35 fps
PIPE REACH ID No. p13
From: mh10 To: junction
Pipe Diameter: 2.00 ft n: 0.0120
Pipe Length 85.00 ft s: 0.0068
Up invert 388.66 ft down invert: 388.08
Collection Area: 33 .78 Ac.
Design Flow 26.81 cfs Dsgn Depth: ft
Pipe Capacity 21 .84 cfs
Design Vel 8 .54 fps Travel Time: 0.17 min
Pipe Full Vel 7.13 fps
(surcharged tt)
PIPE REACH ID No. p14
From: mh2 To: mhE
Pipe Diameter: 2.00 ft n: 0.0120
Pipe Length 50.00 ft s: 0.0026
Up invert 404.14 ft down invert: 404 .01
Collection Area: 31.60 Ac.
Design Flow 15.13 cfs Dsgn Depth: ft
Pipe Capacity 13.48 cfs
Design Vel 4.82 fps Travel Time: 0.17 min
Pipe Full Vel 4 .40 fps
(surcharged tt)
PIPE REACH ID No. p15
From: weir To: mhB
Pipe Diameter: 2.00 ft n: 0.0120
Pipe Length 161.40 ft s: 0.0018
Up invert 403 .50 ft down invert: 403 .21
Collection Area: 31.60 Ac.
Design Flow 3 .50 cfs Dsgn Depth: 1. 20 ft
Pipe Capacity 11.20 cfs
Design Vel 2.99 fps Travel Time: 0.90 min
Pipe Full Vel 3 .66 fps
1/ 8/96 Ch2M Hill - Bellevue, WA page 6
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
REACH SUMMARY
PIPE REACH ID No. p2
From: mhA To: mh2
Pipe Diameter: 2 .00 ft n: 0. 0120
Pipe Length 220. 23 ft s: 0.0025
Up invert 404 . 80 ft down invert: 404.24
Collection Area: 9. 31 Ac.
Design Flow 5.97 cfs Dsgn Depth: 1.02 ft
Pipe Capacity 13 . 33 cfs
Design Vel 3 . 91 fps Travel Time: 0.94 min
Pipe Full Vel 4 . 35 fps
PIPE REACH ID No. p3
From: mh3 To: mhA
Pipe Diameter: 2 .00 ft n: 0.0120
Pipe Length 235. 36 ft s: 0.0025
Up invert 405.50 ft down invert: 404 .90
Collection Area: 9. 31 Ac.
Design Flow 5.97 cfs Dsgn Depth: 1.02 ft
Pipe Capacity 13 . 35 cfs
Design Vel 3.91 fps Travel Time: 1.00 min
Pipe Full Vel 4 . 36 fps
PIPE REACH ID No. p5
From: mh5 To: mh6
Pipe Diameter: 1.50 ft n: 0.0120
Pipe Length 410. 12 ft s: 0.0040
Up invert 403.45 ft down invert: 401.83
Collection Area: 5.44 Ac.
Design Flow 4.08 cfs Dsgn Depth: 0.81 ft
Pipe Capacity 7.71 cfs
Design Vel 4.19 fps Travel Time: 1.63 min
Pipe Full Vel 4.48 fps
PIPE REACH ID No. p6
From: mh6 To: mh7
Pipe Diameter: 1.50 ft n: 0.0120
Pipe Length 240.05 ft s: 0.0112
Up invert 401.62 ft down invert: 398.92
Collection Area: 19.92 Ac.
Design Flow 14.79 cfs Dsgn Depth: ft
Pipe Capacity 13.02 cfs
Design Vel 8.37 fps Travel Time: 0.48 min
Pipe Full Vel 7.56 fps
(surcharged tt)
1/ 8/96 Ch2M Hill - Bellevue, WA page 7
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
---------------------------------------------------------------------
---------------------------------------------------------------------
REACH SUMMARY
PIPE REACH ID No. p7
From: mh7 To: mh8
Pipe Diameter: 1.50 ft n: 0.0120
Pipe Length 120.42 ft s: 0.0329
Up invert 398. 74 ft down invert: 394 .78
Collection Area: 24 .49 Ac.
Design Flow 18.67 cfs Dsgn Depth: 0. 38 ft
Pipe Capacity 22 .26 cfs
Design Vel 13 .26 fps Travel Time: 0.15 min
Pipe Full Vel 12 .93 fps
PIPE REACH ID No. p8
From: mh8 To: mh9
Pipe Diameter: 1.50 ft n: 0.0120
Pipe Length 250. 20 ft s: 0.0189
Up invert 394.78 ft down invert: 390.05
Collection Area: 31 . 39 Ac.
Design Flow 24.74 cfs Dsgn Depth: ft
Pipe Capacity 16.88 cfs
Design Vel 14.00 fps Travel Time: 0.30 min
Pipe Full Vel 9.80 fps
(surcharged tt)
PIPE REACH ID No. p9
From: mh9 To: mh10
Pipe Diameter: 2.00 ft n: 0.0120
Pipe Length 90.00 ft s: 0.0143
Up invert 390.05 ft down invert: 388.76
Collection Area: 33 .78 Ac.
Design Flow 26.81 cfs Dsgn Depth: 0.50 ft
Pipe Capacity 31.65 cfs
Design Vel 10.61 fps Travel Time: 0.14 min
Pipe Full Vel 10. 34 fps
LEVEL POOL REACH ID No. pond
In & Out Hydrograph No. :
Storage Structure Id. . . : pond
Discharge Structure Id. : weir
Outflow Hydrograph Peak: 0.00 cfs
Outflow Peak Time. . . . . . : 0.00 hrs
Peak Detention Stage. . . : 0. 00 ft
Maximum Storage Volune. : 0.00 cf
1/ 8/96 Ch2M Hill - Bellevue , WA page 7
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
---------------------------------------------------------------------
---------------------------------------------------------------------
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. junction
Location : Junction Structure to Arches North 1980 . 0000
Str Type : East 565 . 0000
Str Cat : Dummy Structure Rim Elev 392. 0000
Str Diam : 72 . 00 in Bottom El : 388 . 0800
Cont Area: Hgrade El : 391 . 5800 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 181 Exit: 0 . 362 App Vel: 0 . 276 Junct: 0 . 031 Bend: 0 . 336
Reach <Invert> <Diam> < n > <End>
p13 388 . 080 24 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mhl
Location : Node 14 , D4-1 North 555 . 0000
Str Type : --- East 1910 . 0000
Str Cat : Stm Manhole Rim Elev 437 . 8200
Str Diam : 48 . 00 in Bottom El: 426 . 1100
Cont Area: B12 Hgrade El : 429 .4199 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 102 Exit: 0 . 205 App Vel: 0 . 000 Junct: 0 . 000 Bend: 0 . 000
Reach <Invert> <Diam> < n > <End>
pl 426 . 110 12 . 00 0 . 012 Upper
EXISTING STRUCTURE REACH ID No. mh10
Location : Node 9 , C8-19 North 1980 . 0000
Str Type : --- East 650 . 0000
Str Cat : Stm Manhole Rim Elev 394. 8500
Str Diam : 48 . 00 in Bottom El: 388. 6600
Cont Area: Hgrade El: 394. 6633 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss: 0 . 566 Exit: 1 . 131 App Vel: 1 . 131 Junct: 0 . 000 Bend: 1 . 506
Reach <Invert> <Diam> < n > <End>
p9 388 . 760 24 . 00 0 . 012 Lower
p13 388 . 660 24 . 00 0 . 012 Upper
1/ 8/96 Ch2M Hill - Bellevue, WA page 8
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mh2
Location Node 14 , D4-3 North 570 . 0000
Str Type --- East 1320 . 0000
Str Cat Stm Manhole Rim Elev 412 . 4700
Str Diam 60 . 00 in Bottom El: 404 . 1400
Cont Area: B15 Hgrade El: 408 . 1881 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss: 0 . 268 Exit: 0 . 537 App Vel: 0 . 000 Junct: 0 . 000 Bend: 0 . 000
Reach <Invert> <Diam> < n > <End>
p14 404 . 140 24 . 00 0 . 012 Upper
pl 407 . 270 12 . 00 0 . 012 Lower
p2 404 . 240 24 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh3
Location Node 14 .C4-2 North 567 . 0000
Str Type East 865 . 0000
Str Cat Stm Manhole Rim Elev 409 . 8800
Str Diam 60 . 00 in Bottom El : 405 . 5000
Cont Area: B14 Hgrade El: 408 . 5698 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 028 Exit: 0 . 056 App Vel: 0 . 000 Junct: 0 . 000 Bend: 0 . 000
Reach <Invert> <Diam> < n > <End>
p3 405 . 500 24 . 00 0 . 012 Upper
EXISTING STRUCTURE REACH ID No. mh5
Location : Node 14 .C3-4 North 870 . 0000
Str Type : East 615 . 0000
Str Cat : Stm Manhole Rim Elev 413 . 5800
Str Diam : 48 . 00 in Bottom El: 403 . 4500
Cont Area: B9 Hgrade El: 411 . 2758 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 041 Exit: 0 . 083 App Vel: 0 . 000 Junct: 0 . 000 Bend: 0 . 000
Reach <Invert> <Diam> < n > <End>
p5 403 . 450 18 . 00 0 . 012 Upper
1/ 8/96 Ch2M Hill - Bellevue, WA page 9
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
---------------------------------------------------------------------
---------------------------------------------------------------------
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mh6
Location : Node 14 , C3-10 North 1280 . 0000
Str Type : --- East 625 . 0000
Str Cat : Stm Manhole Rim Elev 411 . 9200
Str Diam : 60 . 00 in Bottom El: 401 . 6200
Cont Area: B7 Hgrade El: 410 . 6265 ft
Bend. . . . . : No special shape
Ent type . : Str Diam :
Ent Loss : 0 . 544 Exit: 1 . 087 App Vel: 0 . 094 Junct: 0 . 049 Bend: 0 . 122
Reach <Invert> <Diam> < n > <End>
p6 401 . 620 18 . 00 0 . 012 Upper
p5 401 . 830 18 . 00 0 . 012 Lower
p12 401 . 660 24 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh7
Location : Node 14 , C2-7 North 1520 . 0000
Str Type : --- East 630 . 0000
Str Cat : Stm Manhole Rim Elev 404 . 8100
Str Diam : 48 . 00 in Bottom El: 398. 7400
Cont Area: B5 Hgrade El: 404 . 8870 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 867 Exit: 1 . 734 App Vel : 1 . 087 Junct: 0 . 212 Bend: 0 . 016
Reach <Invert> <Diam> < n > <End>
p7 398 . 740 18 . 00 0 . 012 Upper
p6 398 . 920 18. 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mh8
Location : Node 14 , C2-4 North 1640 . 0000
Str Type : -- East 640 . 0000
Str Cat : Stm Manhole Rim Elev 399 . 8200
Str Diam : 48 . 00 in Bottom El: 394 . 7800
Cont Area: B3 Hgrade El: 399 . 9200 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 1 . 522 Exit: 3 . 043 App Vel: 1 . 734 Junct: 0 . 407 Bend: 0 . 019
Reach <Invert> <Diam> < n > <End>
p8 394. 780 18 . 00 0 . 012 Upper
p7 394. 780 18 . 00 0 . 012 Lower
1/ 8/96 Ch2M Hill - Bellevue, WA page 10
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mh9
Location : Node 9 , C8-18 North 1890 . 0000
Str Type : --- East 650 . 0000
Str Cat : Stm Manhole Rim Elev 395 . 5800
Str Diam : 48 . 00 in Bottom El : 390 . 0500
Cont Area: B1 Hgrade El : 395 . 6800 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 566 Exit: 1 . 131 App Vel : 3 . 043 Junct: 0 . 207 Bend: 4 . 050
Reach <Invert> <Diam> < n > <End>
p9 390 . 050 24 . 00 0 . 012 Upper
p8 390 . 050 18 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mhA
Location Node 14 .C4-1 North 580 . 0000
Str Type East 1100 . 0000
Str Cat Stm Manhole Rim Elev 410 . 7400
Str Diam 48 . 00 in Bottom El: 404 . 8000
Cont Area: Hgrade El: 408 . 3472 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 028 Exit: 0 . 056 App Vel: 0 . 056 Junct: 0 . 000 Bend: 0 . 001
Reach <Invert> <Diam> < n > <End>
p2 404 . 800 24 . 00 0 . 012 Upper
p3 404 . 900 24 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mhB
Location : Node 14 . C3-1 North 875 . 0000
Str Type : East 1125 . 0000
Str Cat : Stm Manhole Rim Elev 409 . 2900
Str Diam : 60 . 00 in Bottom El: 403 . 1100
Cont Area: B10 Hgrade El : 409 . 3900 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 018 Exit: 0 . 035 App Vel: 0 . 019 Junct: 0 . 005 Bend: 0 . 019
Reach <Invert> <Diam> < n > <End>
p15 403 . 210 24 . 00 0 . 012 Lower
pll 403 . 110 24 . 00 0 . 012 Upper
1/ 8/96 Ch2M Hill - Bellevue, WA page 11
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
STRUCTURE REPORT
EXISTING STRUCTURE REACH ID No. mhC
Location : North 1260 . 0000
Str Type : East 1150 . 0000
Str Cat : Stm Manhole Rim Elev 416 . 0800
Str Diam : 60 . 00 in Bottom El: 402 .4500
Cont Area: B7 Hgrade El : 411 . 3120 ft
Bend. . . . . : No special shape
Ent type . : Str Diam :
Ent Loss : 0 . 047 Exit: 0 . 094 App Vel : 0 . 035 Junct: 0 . 014 Bend: 0 . 047
Reach <Invert> <Diam> < n > <End>
p12 402 . 450 24 . 00 0 . 012 Upper
p11 402 . 500 24 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. mhE
Location End of discharge pipe to pond North 620 . 0000
Str Type --- East 1320 . 0000
Str Cat Dummy Structure Rim Elev 412 . 0000
Str Diam 48 . 00 in Bottom El: 404 . 0100
Cont Area: Hgrade El: 0 . 0000 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss : 0 . 069 Exit: 0 . 139 App Vel : 0 . 205 Junct: 0 . 065 Bend: 0 . 002
Reach <Invert> <Diam> < n > <End>
p14 404 . 010 24 . 00 0 . 012 Lower
EXISTING STRUCTURE REACH ID No. weir
Location : Discharge Structure to p15 North 830 . 0000
Str Type : --- East 1280 . 0000
Str Cat : Dummy Structure Rim Elev 407 . 0000
Str Diam : 48 . 00 in Bottom El: 403 . 5000
Cont Area: Hgrade El: 407 . 1000 ft
Bend. . . . . : No special shape
Ent type. : Str Diam :
Ent Loss: 0 . 010 Exit: 0 . 019 App Vel: 0 . 000 Junct: 0 . 000 Bend: 0 . 000
Reach <Invert> <Diam> < n > <End>
p15 403 . 500 24 . 00 0 . 012 Upper
Results
• Hydrograph Summary
• History of Hydrograph Activity
1/ 8/96 Ch2M Hill - Bellevue , WA page 5
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min. cf\AcFt Acres
1 11 . 278 480 164267 c f 33 . 78 2-Year Design Storm
2 18 . 595 480 266901 c f 33 . 78 10-Year Design Storm
3 22 . 703 480 325238 cf 33 . 78 25-Year Design Storm
4 26 . 814 480 384129 c f 33 . 78 100-Year Design Storm
3/ 1/96 Ch2M Hill - Bellevue, WA page 1
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
HISTORY OF HYDROGRAPH ACTIVITY
Date of Session: 10/17/95
CLEARHIS
ZERO 1 20
REMARK r rrtr,t r*r*,rrtrt r trr**rr***►*►**r****rt,t r rt****,t****r rr rv.*t t*,tt,t**t t tr
START OUT BY ROUTING THE 2 YEAR STORM THROUGH HYDROGRAPH 1
LSTEND *w,r,r r*:sr,t**rrr,►r,►,rt,r*w,►,r,r t*t,t*t,r,t,twr*****r*r*r,►,r,r**,►f*,t*,rrw r r r r*r,r*
CHANGE 112 YR STORM" 2.00 PRECIP
BO B1 B10 B12 B14 B15
B3 B5 B6 B7 B9
LSTEND
ROUTE HYDROGRAPH 1 THROUGH REACH nl
Network n2
Reach <AREA> <Act Q> <Q Full> % Full Ndepth <Diam> <NVel> <FVeL> Carea
p5 5.44 1.54 7.71 20.02 12.33 18.00 3.24 4.06 B9
Network nl
Reach <AREA> <Act Q> <Q FULL> % Full Ndepth <Diam> <NVeI> <FVeL> Carea
p15 31.60 3.50 11.20 31.25 14.41 24.00 2.99 3.32
p11 6.48 1.79 10.51 17.03 17.04 24.00 2.37 3.11 B10
p12 10.48 2.92 10.25 28.46 14.89 24.00 2.67 3.03 B7
p6 19.92 5.59 13.02 42.93 9.41 18.00 6.71 6.85 67
p7 24.49 7.44 22.26 33.42 7.46 18.00 10.75 11.71 B5
p8 31.39 10.33 16.88 61.21 7.34 18.00 9.48 8.88 83
p9 33.78 11.28 31.65 35.64 10.31 24.00 8.74 9.36 B1
p13 33.78 11.28 21.84 51.65 12.78 24.00 6.63 6.46
HGRADE hgradel
n1
n2
n3
SUBMERGED 389.08
LSTEND
HGLINE hgradel
Hydraulic Gradeline for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent_HGL EntLoss ExtLoss Outlet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
junction 389.08
mh10 junction 11.28 0.72 tw & do <dc: Inlet CtrL Assumed 389.31 0.20 0.27 0.00 389.37 394.85
mh9 mh10 11.28 4.51 tw & do <dc: Inlet Ctrl Assumed 390.69 0.53 0.71 0.04 390.91 395.58
mh8 mh9 10.33 5.32 tw & do <dc: Inlet Ctrl Assumed 397.13 0.28 0.00 0.08 396.93 399.82
mh7 mh8 7.44 0.51 397.45 0.14 0.28 397.86 399.38 0.16 0.00 0.04 399.26 404.81
3/ 1/96 Ch2M Hill - Bellevue, WA page 2
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
---------------------------------------------------------------------
---------------------------------------------------------------------
HISTORY OF HYDROGRAPH ACTIVITY
mh6 mh7 5.59 44.36 tw 8 do <dc: Inlet Ctrl Assumed 402.11 0.01 0.02 0.01 402.12 411.92
mhC mh6 2.92 5.45 403.25 0.01 0.01 403.27 402.78 0.01 0.01 0.00 403.27 416.08
mhB mhC 1.79 0.21 403.98 0.00 0.01 403.99 403.36 0.02 0.02 -0.01 403.98 409.29
weir mhB 3.50 0.33 404.48 0.01 0.02 404.51 403.86 0.00 0.00 0.00 404.51 407.00
mh6 402.86
mh5 mh6 1.54 0.11 403.88 0.01 0.01 403.90 403.70 0.00 0.00 0.00 403.90 413.58
mh2 408.19
mhA mh2 5.97 0.13 408.32 0.03 0.06 408.40 405.24 0.06 0.00 0.00 408.35 410.74
mh3 mhA 5.97 0.14 408.49 0.03 0.06 408.57 405.94 0.00 0.00 0.00 408.57 409.88
REMARK
ROUTING THE 10 YEAR STORM THROUGH HYDROGRAPH 2
LSTEND
CHANGE 1110 YR STORM" 2.90 PRECIP
BO 81 B10 B12 814 B15
83 B5 B6 67 B9
LSTEND
ROUTE HYDROGRAPH 2 THROUGH REACH n1
Network n2
Reach <AREA> <Act 0> <p FULL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p5 5.44 2.73 7.71 35.39 10.30 18.00 3.78 4.06 B9
Network nl
Reach <AREA> <Act 0> <p Full> % Full Ndepth <Diam> 0W> <FVeL> Carea
p15 31.60 3.50 11.20 31.25 14.41 24.00 2.99 3.32
p11 6.48 3.17 10.51 30.14 14.60 24.00 2.78 3.11 810
p12 10.48 5.16 10.25 50.35 12.59 24.00 3.09 3.03 B7
p6 19.92 9.88 13.02 75.93 12.37 18.00 7.64 6.85 B7
p7 24.49 12.71 22.26 57.08 7.80 18.00 12.30 11.71 B5
p8 31.39 17.11 --------Pressure Flow-------- 9.68 63
p9 33.78 18.60 31.65 58.76 10.16 24.00 9.91 9.36 B1
p13 33.78 18.60 21.84 85.16 18.07 24.00 7.33 6.46
HGRADE hgradel
nl
n2
n3
SUBMERGED 389.58
LSTEND
HGLINE hgradel
3/ 1/96 Ch2M Hill - Bellevue, WA page 3
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
---------------------------------------------------------------------
---------------------------------------------------------------------
HISTORY OF HYDROGRAPH ACTIVITY
Hydraulic Gradeline for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent HGL EntLoss ExtLoss Outlet Inlet AppHead 8ndHead JunHead HeadWtr -cb/mh-
junction 389.58
mh10 junction 18.60 0.59 tw 8 do <dc: Inlet Ctrl Assumed 391.39 0.54 0.72 0.00 391.57 394.85
mh9 mh10 18.60 0.52 392.08 0.27 0.54 392.90 392.77 1.46 1.94 0.10 393.48 395.58
mh8 mh9 17.11 5.63 399.11 0.73 1.46 401.29 399.50 0.80 0.01 0.20 399.92* 399.82
mh7 mh8 12.71 1.49 401.41 0.40 0.80 402.62 401.78 0.49 0.01 0.10 402.24 404.81
mh6 mh7 9.88 1.80 404.04 0.24 0.49 404.77 403.86 0.04 0.05 0.02 404.81 411.92
mhC mh6 5.16 0.23 405.04 0.02 0.04 405.10 402.87 0.02 0.02 0.01 405.11 416.08
mhB mhC 3.17 0.06 405.18 0.01 0.02 405.20 403.45 0.02 0.02 -0.00 405.20 409.29
weir mhB 3.50 0.03 405.22 0.01 0.02 405.25 403.86 0.00 0.00 0.00 405.25 407.00
mh6 404.81
mh5 mh6 2.73 0.23 405.04 0.02 0.04 405.10 403.77 0.00 0.00 0.00 405.10 413.58
mh2 408.19
mhA mh2 5.97 0.13 408.32 0.03 0.06 408.40 405.24 0.06 0.00 0.00 408.35 410.74
mh3 mhA 5.97 0.14 408.49 0.03 0.06 408.57 405.94 0.00 0.00 0.00 408.57 409.88
REMARK
ROUTING THE 25 YEAR STORM THROUGH HYDROGRAPH 3
LSTEND
CHANGE 1125 YR STORM" 3.40 PRECIP
BO B1 B10 B12 814 815
83 B5 B6 87 B9
LSTEND
ROUTE HYDROGRAPH 3 THROUGH REACH nl
Network n2
Reach <AREA> <Act G> <p Full> % Full Ndepth <Diam> <NVeI> <FVeI> Carea
p5 5.44 3.40 7.71 44.13 9.27 18.00 4.01 4.06 B9
Network n1
Reach <AREA> <Act G> <p Full> % Full Ndepth <Diam> <NVeI> <FVeI> Carea
p15 31.60 3.50 11.20 31.25 14.41 24.00 2.99 3.32
p11 6.48 3.95 10.51 37.60 13.38 24.00 2.95 3.11 B10
p12 10.48 6.44 10.25 62.81 14.45 24.00 3.26 3.03 B7
p6 19.92 12.33 13.02 94.71 15.08 18.00 7.80 6.85 B7
p7 24.49 15.68 22.26 70.46 6.28 18.00 12.88 11.71 85
p8 31.39 20.92 --------Pressure Flow-------- 11.84 83
p9 33.78 22.70 31.65 71.74 8.18 24.00 10.33 9.36 B1
p13 33.78 22.70 --------Pressure Flow-------- 7.23
HGRADE hgradel
nl
3/ 1/96 Ch2M Hill - Bellevue, WA page 4
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
HISTORY OF HYDROGRAPH ACTIVITY
n2
n3
SUBMERGED 391.08
LSTEND
HGLINE hgradel
Hydraulic Gradeline for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent_HGL EntLoss ExtLoss OutLet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
junction 391.08
mh10 junction 22.70 0.73 391.81 0.41 0.81 393.02 392.07 0.81 1.08 0.00 393.29 394.85
mh9 WO 22.70 0.77 394.06 0.41 0.81 395.27 393.45 2.18 2.90 0.15 395.68* 395.58
mh8 mh9 20.92 8.41 404.09 1.09 2.18 407.36 401.35 1.22 0.01 0.29 399.92* 399.82
mh7 mh8 15.68 2.28 402.20 0.61 1.22 404.03 402.86 0.76 0.01 0.15 403.44 404.81
mh6 mh7 12.33 2.80 406.24 0.38 0.76 407.37 404.55 0.07 0.09 0.03 407.43 411.92
mhC mh6 6.44 0.36 407.79 0.03 0.07 407.89 402.91 0.02 0.03 0.01 407.90 416.08
mhB mhC 3.95 0.10 408.00 0.01 0.02 408.04 403.49 0.02 0.02 0.00 408.04 409.29
weir mhB 3.50 0.03 408.08 0.01 0.02 408.10 403.86 0.00 0.00 0.00 407.10* 407.00
mh6 407.43
mh5 mh6 3.40 0.37 407.79 0.03 0.06 407.88 403.81 0.00 0.00 0.00 407.88 413.58
*2 408.19
mhA mh2 5.97 0.13 408.32 0.03 0.06 408.40 405.24 0.06 0.00 0.00 408.35 410.74
mh3 mhA 5.97 0.14 408.49 0.03 0.06 408.57 405.94 0.00 0.00 0.00 408.57 409.88
REMARK
ROUTING THE 100 YEAR STORM THROUGH HYDROGRAPH 4
LSTEND
CHANGE 11100 YR PRECIP" 3.90 PRECIP
BO 81 810 B12 B14 B15
B3 85 B6 B7 B9
LSTEND
ROUTE HYDROGRAPH 4 THROUGH REACH nl
Network n2
Reach <AREA> <Act 0> <p FuLI> % Full Ndepth <Diam>"<NVel> <FVeI> Carea
p5 5.44 4.08 7.71 52.92 9.73 18.00 4.19 4.06 B9
Network n1
Reach <AREA> <Act G> <p Full> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p15 31.60 3.50 11.20 31.25 14.41 24.00 2.99 3.32
p11 6.48 4.74 10.51 45.11 12.21 24.00 3.09 3.11 B10
p12 10.48 7.72 10.25 75.34 16.39 24.00 3.38 3.03 B7
p6 19.92 14.79 --------Pressure Flow-------- 8.37 B7
3/ 1/96 Ch2M Hill - Bellevue, WA page 5
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
Alternative 3A - Diversion
HISTORY OF HYDROGRAPH ACTIVITY
p7 24.49 18.67 22.26 83.89 4.62 18.00 13.26 11.71 B5
p8 31.39 24.74 --------Pressure Flow-------- 14.00 83
p9 33.78 26.81 31.65 84.73 6.01 24.00 10.61 9.36 81
p13 33.78 26.81 --------Pressure Flow-------- 8.54
HGRADE hgradel
nl
n2
n3
SUBMERGED 391.58
LSTEND
HGLINE hgradel
Hydraulic Gradeline for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent_HGL EntLoss ExtLoss OutLet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
junction 391.58
mh10 junction 26.81 1.01 392.59 0.57 1.13 394.29 392.89 1.13 1.51 0.00 394.66 394.85
mh9 mh10 26.81 1.07 395.73 0.57 1.13 397.43 394.28 3.04 4.05 0.21 395.68* 395.58
mh8 mh9 24.74 11.76 407.44 1.52 3.04 412.01 403.57 1.73 0.02 0.41 399.92* 399.82
mh7 mh8 18.67 3.22 403.14 0.87 1.73 405.75 404.16 1.09 0.02 0.21 404.89 404.81
mh6 mh7 14.79 4.03 408.92 0.54 1.09 410.55 405.40 0.09 0.12 0.05 410.63 411.92
mhC mh6 7.72 0.52 411.15 0.05 0.09 411.29 402.95 0.04 0.05 0.01 411.31 416.08
mhB mhC 4.74 0.14 411.46 0.02 0.04 411.51 403.51 0.02 0.02 0.00 409.39* 409.29
weir mhB 3.50 0.03 409.42 0.01 0.02 409.45 403.86 0.00 0.00 0.00 407.10* 407.00
mh6 410.63
mh5 mh6 4.08 0.52 411.15 0.04 0.08 411.28 403.84 0.00 0.00 0.00 411.28 413.58
mh2 408.19
mhA mh2 5.97 0.13 408.32 0.03 0.06 408.40 405.24 0.06 0.00 0.00 408.35 410.74
mh3 mhA 5.97 0.14 408.49 0.03 0.06 408.57 405.94 0.00 0.00 0.00 408.57 409.88
End program file BASIN O.PGM
HEN Input and Results
• Input and Program
• System Schematic
• Hydrograph at Pond
• Runoff Summary
FLOOD HYDROGRAPH PACKAGE (HEC-1) ' U.S.ARMY CORPS OF ENGINEERS '
SEPTEMBER 1990 HYDROLOGIC ENGINEERING CENTER
' VERSION 4.0 • ' 609 SECOND STREET
DAVIS,CALIFORNIA 95616
' RUN DATE 10/18/1995 TIME 19:36:08• (916)756-1104
X X X)00000C XX 00( X
X XX X X XX
X XX X X
)000000C XXXX X XXXXX X
X XX X X
X XX X X X
X X X)00000C XX 00( XXX
THIS PROGRAM REPLACES ALL PREVIOUS VERSIONS OF HEC-1 KNOWN AS HEC1(JAN 73),HECIGS,HECIDB,
AND HECI KW.
THE DEFINITIONS OF VARIABLES-RTIMP-AND-RTIOR-HAVE CHANGED FROM THOSE USED WITH THE 1973-
STYLE INPUT STRUCTURE
THE DEFINITION OF-AMSKK-ON RM-CARD WAS CHANGED WITH REVISIONS DATED 28 SEP 81.THIS IS THE
FORTRAN77 VERSION
NEW OPTIONS:DAMBREAK OUTFLOW SUBMERGENCE,SINGLE EVENT DAMAGE CALCULATION,DSS:WRTTE
STAGE FREQUENCY,
DSS:READ TIME SERIFS AT DESIRED CALCULATION INTERVAL LOSS RATE:GREEN AND AMPT INFILTRATION
KINEMATIC WAVE:NEW FINITE DIFFERENCE ALGORITHM
1 HEC-1 INPUT PAGE 1
LINEID.......1.......2......3.......4.......5.......6.......7.......8.......9 ....10
1 ID City of Renton:NE 10th/Anacortes Ct Storm System Improvement
2 ID Alt.3A:Diversion and Pond Analysis
3 ID HEC-1 Hydrologic Analysis for Design
4 ID 25-Year,24-Hour Design Storm,Existing Site Conditions
5 ID SCS Type 1A Preicpitation Distribution,10 min Time Increment
6 ID Run at 5 Min Time Step
7 ID Input Filename:3AHEC.DAT,Revised 10/9/95
'DIAGRAM
8 IT 5 0 300
9 IN 10
10 10 5 0
11 KK SUBB12
12 KM Runoff from Drainage Subarea B12
area in square miles-multiplied by 100 to get significant digits
13 BA 1.997
'2-5-Year,24-Hour Event Precipitation estimated at 3A inches from King County
'Surface Water Design Manual Isopluvial Map
14 PB 3.40
15 PC .004 .008 .012 .016 .020 .024 .028 .032 .036 .040
16 PC .045 .050 .055 .060 .065 .070 .076 .082 .088 .094
17 PC .100 .106 .113 .120 .127 .134 .141 .148 .156 .164
18 PC .173 .181 .189 .197 .207 .216 .226 .235 .245 .254
19 PC .268 .281 .294 .312 .3M .364 .418 .445 .463 .477
20 PC .490 .504 .512 .521 .5W .539 .548 .556 .565 .574
21 PC .583 .592 .600 .609 .616 .624 .631 .638 .645 .652
22 PC .660 .667 .674 .681 .698 .696 .701 .707 .713 .718
23 PC .724 .730 .736 .741 .747 .753 .758 .764 .769 .774
24 PC .779 .784 .789 .794 .799 .804 .809 .814 .819 .824
25 PC .828 .832 .836 .840 .844 .848 .852 .856 .860 .864
26 PC .868 .972 .876 .880 .884 .898 .892 .896 .900 .904
27 PC .908 .912 .916 .920 .924 .928 .932 .936 .940 .944
28 PC .948 .952 .956 .960 .964 .968 .972 .976 .980 .994
29 PC .988 .992 .996 1.000
30 LS 0 86.3
31 UD .412
•route Subarea B12 through pipe with one time-step lag
32 KK RTB12
33 RT 0 1 1
34 KK SUBB15
35 KM Runoff from Drainage Subarea B15
•area in square miles-multiplied by 100 to get significant digits
36 BA .775
37 LS 0 89.8
38 UD .361
39 KK SUBB13
40 KM Runoff from Drainage Subarea B13
•area in square miles-multiplied by 100 to get significant digits
41 BA 1.273
42 LS 0 90.6
43 UD .169
•route Subarea B13 through pipe with one time-step lag
1 HEC-1 INPUT PAGE 2
LINE ID.......1.......2......3......A.......5.......6.......7.......8.......9......10
44 KK RTB13
45 RT 0 1 1
46 KK SUBB14
47 KM Runoff from Drainage Subarea B14
•area in square miles-multiplied by 100 to get significant digits
48 BA .181
49 LS 0 91.5
50 UD .170
51 KK SUBNEW
52 KM Runoff from Drainage Subarea NEW
•area in square miles-multiplied by 100 to get significant digits
53 BA .711
54 IS 0 87.9
55 UD .592
56 KK COM1
57 KM Combine flows from Subareas B12-1314&BNEW at Detention Pond
58 HC 5
59 KK DPOND
60 KM Storage Routing of Combined Runoff through Detention Pond
•assumes single submerged orifice(8.0 inch diameter)at elevation 402.5
•volume and outflow input multiplied by 100 for consistency with input
61 KO 1
62 RS 1 EL.EV 403.5
63 SV 0 61 121 182 212
64 SE 403.5 404.5 405.5 406.5 407.0
65 SQ 0 0 170 250 1100
66 KK SUBBIO
67 KM Runoff from Drainage Subarea B10
'area in square miles-multiplied by 100 to get significant digits
68 BA 1.012
69 LS 0 91.0
70 UD .259
71 KK COM2
72 KM Combine flows from Pond and Subarea B10 after Detention Pond
73 HC 2
route Subarea B10(combined w/Pond)through pipe with one time-step lag
74 KK RT1310
75 RT 0 1 1
76 KK SUBB9
77 KM Runoff from Drainage Subarea B9
area in square miles-multiplied by 100 to get significant digits
78 BA .228
79 LS 0 91.0
80 UD .194
1 HEC-1 INPUT PAGE 3
LINEID.......1.......2.......3.......4.......5.......6.......7.......8.......9......10
81 KK SUBB8
82 KM Runoff from Drainage Subarea B8
'area in square miles-multiplied by 100 to get significant digits
83 BA .622
84 LS 0 91.0
85 UD .241
86 KK SUBB7
87 KM Runoff from Drainage Subarea B7
area in square miles-multiplied by 100 to get significant digits
88 BA .625
89 LS 0 91.0
90 UD .248
91 KK SUBB6
92 KM Runoff from Drainage Subarea B6
'area in square miles-multiplied by 100 to get significant digits
93 BA .958
94 LS 0 91.0
95 UD .210
% KK COM3
97 KM Combine flows from COM2& Subareas B6-B9 @ Node 6
98 HC 5
99 KK SUBBS
100 KM Runoff from Drainage Subarea B5
area in square miles-multiplied by 100 to get significant digits
101 BA .372
102 LS 0 %.9
103 UD .048
104 KK SUBB4
105 KM Runoff from Drainage Subarea B4
area in square miles-multiplied by 100 to get significant digits
106 BA .342
107 IS 0 %.2
108 UD .140
109 KK SUBB3
110 KM Runoff from Drainage Subarea B3
•area in square miles-multiplied by 100 to get significant digits
111 BA .397
112 IS 0 95.8
113 UD .158
114 KK SUBB2
115 KM Runoff from Drainage Subarea B2
•area in square miles-multiplied by 100 to get significant digits
116 BA .686
117 IS 0 97.1
118 UD .144
1 HEC-1 INPUT PAGE 4
LINE ID.......1.......2......3.......4.......5.......6.......7.......8.......9......10
119 KK COM4
120 KM Combine flows from COM3& Subareas B2-B5 @ Node 8
121 HC 5
122 KK SUBB1
123 KM Runoff from Drainage Subarea Bl
•area in square miles-multiplied by 100 to get significant digits
124 BA .373
125 IS 0 95.6
126 UD .240
127 KK SUBBO
128 KM Runoff from Drainage Subarea BO
•area in square miles-multiplied by 100 to get significant digits
129 BA .059
130 IS 0 84.4
131 UD .680
132 KK COMS
133 KM Combine flows from COM4& Subareas Bl&BO @ Node 10
134 HC 3
135 ZZ
1
SCHEMATIC DIAGRAM OF STREAM NETWORK
INPUT
LINE (V)ROUTING (—>)DIVERSION OR PUMP FLOW
NO. ()CONNECTOR (<—)RETURN OF DIVERTED OR PUMPED FLOW
11 SUBB12
V
V
32 RTB12
34 SUBB15
39 SUBB13
V
V
44 RTB13
46 SUBB14
51 SUBNEW
56 COM1................................................
V
V
59 DPOND
66 SUBB10
71 COM2...........
V
V
74 RTB10
76 SUBB9
81 SUBB8
86 SUBB7
91 SUBB6
96 COM3................................................
99 SUBB5
104 SUBB4
109 SUBB3
114 SUBB2
119 COM4..............................................
122 SUBBI
127 SUBBO
132 COM5.......................
RUNOFF ALSO COMPUTED AT THIS LOCATION
FLOOD HYDROGR*APH PACKAGE (HEC-1) U.S.ARMY CORPS OF ENGINEERS
SEPTEMBER 1990 HYDROLOGIC ENGINEERING CENTER
VERSION 4.0 609 SECOND STREET
' DAVIS,CALIFORNIA 95616
RUN DATE 10/18/1995 TIME 1936:08' (916)756-1104
.f i.H....f HH.M111fH1M11fiff t1H1f
City of Renton:NE loth/Anacortes Ct Storm System Improvement
Alt.3A:Diversion and Pond Analysis
HEC-1 Hydrologic Analysis for Design
25-Year,24-Hour Design Storm,Existing Site Conditions
SCS Type 1A Preicpitation Distribution,10 min.Time Increment
Run at 5 Min Time Step
Input Filename:3AHEC.DAT,Revised 10/9/95
1010 OUTPUT CONTROL VARIABLES
IRRNT 5 PRINT CONTROL
IPLOT 0 PLOT CONTROL
QSCAL 0. HYDROGRAPH PLOT SCALE
IT HYDROGRAPH TIME DATA
NMIN 5 MINUTES IN COMPUTATION INTERVAL
IRATE 1 0 STARTING DATE
IT1ME 0000 STARTING TIME
NQ 300 NUMBER OF HYDROGRAPH ORDINATES
NDDATE 2 0 ENDING DATE
NDTIME 0055 ENDING TIME
ICENT 19 CENTURY MARK
COMPUTATION INTERVAL .08 HOURS
TOTAL TIME BASE 24.92 HOURS
ENGLiSH UNITS
DRAINAGE AREA SQUARE MILES
PRECIPITATION DEPTH INCHES
LENGTH,ELEVATION FEET
FLOW CUBIC FEET PER SECOND
STORAGE VOLUME ACRE-FEET
SURFACE AREA ACC
TEMPERATURE DEGREES FAHRENHEIT
--------Hf--H►-Hf---H►-----fff-----Hf-Hf Hf
59 KK • DPOND '
a.1f.f.1H111f
61 KO OUTPUT CONTROL VARIABLES
PRRNT 1 PRINT CONTROL
IPLOT 0 PLOT CONTROL
QSCAL 0. HYDROGRAPH PLOT SCALE
HYDROGRAPH ROUTING DATA
62 IS STORAGE ROUTING
NSTPS 1 NUMBER OF SUBREACHES
ITYP ELEV TYPE OF INITIAL CONDITION
RSVRIC 403.50 INITIAL CONDITION
X .00 WORKING R AND D COEFFICIENT
63 SV STORAGE .0 61.0 121.0 182.0 212.0
64 SE ELEVATION 403.50 404.50 405.50 406.50 407.00
65 SQ DISCHARGE 0. 0. 170. 250. 1100.
f.1H.1.H,***1***KIHHHH**1KHf.H1*1f.f*t*Hf1H,fH.f11f..1...f.,.....,.f.111f.HKHK1f*1f,.HHIf.HHf Hf*111f 1HH.K.
HYDROGRAPH AT STATION DPOND
**f*f* .1H„f.J.*tK,*..,f-..M.H,.H,HHHKHHK.HKH....H..,1•
DA MON HRMN ORD OUTFLOW STORAGE STAGE*DA MON HRMN ORD OUTFLOW STORAGE STAGE*DA
MON HRMN ORD OUTFLOW STORAGE STAGE
1 0000 1 0. .0 403.5* 1 0820101 200. 143.6 405.9* 1 1640 201 287. 1833 406.5
1 0005 2 0. .0 403.5* 1 0825102 207. 149.2 406.0* 1 1645 202 286. 1833 406.5
1 0010 3 0. .0 403.5* 1 0830103 214. 154.2 406.0* 1 1650 203 284. 183.2 406.5
1 0015 4 0. .0 403.5* 1 0835104 219. 158.7 406.1* 1 1655 204 280. 183.1 406.5
1 0020 5 0. .0 403.5* 1 0940105 225. 162.8 406.2* 1 1700 205 276. 182.9 406.5
1 0025 6 0. .0 403.5* 1 0945106 230. 166.5 406.2* 1 1705 206 272. 182.8 406.5
1 0030 7 0. .0 403.5* 1 0850107 234. 169.7 4063* 1 1710 207 268. 182.6 406.5
1 0035 8 0. .0 403.5* 1 0855108 237. 172.5 4063* 1 1715 208 263. 182.5 406.5
1 0040 9 0. .0 403.5* 1 0900109 241. 175.0 406.4* 1 1720 209 259. 1823 406.5
1 0045 10 0. .0 403.5* 1 0905110 244. 177.2 406.4* 1 1725 210 255. 182.2 406.5
1 0050 11 0. .0 403.5* 1 0910111 246. 179.2 406.5* 1 1730 211 252. 182.1 406.5
1 0055 12 0. .0 403.5* 1 0915112 249. 181.1 406.5* 1 1735 212 250. 182.0 406.5
1 0100 13 0. .0 403.5* 1 0920113 273. 182.8 406.5* 1 1740 213 250. 181.9 406.5
1 0105 14 0. .0 403.5* 1 0925114 313. 184.2 406.5* 1 1745 214 250. 181.7 406.5
1 0110 15 0. .0 403.5* 1 0930115 344. 1853 406.6* 1 1750 215 250. 181.6 406.5
1 0115 16 0. .0 403.5* 1 0935116 367. 186.1 406.6* 1 1755 216 249. 181.5 406.5
1 0120 17 0. .0 403.5* 1 0940117 385. 186.8 406.6* 1 1800 217 249. 181.4 406.5
1 0125 18 0. .0 403.5* 1 0945118 399. 1873 406.6* 1 1805 218 249. 181.3 406.5
1 0130 19 0. .0 403.5* 1 0950119 410. 187.7 406.6* 1 1810 219 249. 181.2 406.5
1 0135 20 0. .0 403.5* 1 0955120 419. 188.0 406.6* 1 1815 220 249. 181.1 406.5
1 014021 0. .0 403.5* 1 1000121 427. 188.2 406.6* 1 1820 221 249. 180.9 406.5
1 0145 22 0. .0 403.5* 1 1005122 434. 188.5 406.6* 1 1825 222 248. 180.8 406.5
1 0150 23 0. .0 403.5* 1 1010123 440. 188.7 406.6* 1 1830 223 248. 180.7 406.5
1 0155 24 0. .0 403.5* 1 1015124 445. 188.9 406.6* 1 1835 224 248. 180.6 406.5
1 0200 25 0. .0 403.5* 1 1020125 449. 189.0 406.6* 1 1840 225 248. 180.5 406.5
1 0205 26 0. .0 403.5* 1 1025126 452. 189.1 406.6* 1 1845 226 248. 180A 406.5
1 0210 27 0. .0 403.5* 1 1030127 454. 189.2 406.6* 1 1850 227 248. 1803 406.5
1 0215 28 0. .0 403.5* 1 1035128 455. 189.2 406.6* 1 1855 228 248. 180.2 406.5
1 0220 29 0. .0 403.5* 1 1040129 456. 1893 406.6* 1 1900 229 247. 180.1 406.5
1 0225 30 0. .0 403.5* 1 1045130 455. 189.2 406.6* 1 1905 230 247. 180.0 406.5
1 023031 0. .0 403.5* 1 1050131 453. 189.2 406.6* 1 1910 231 247. 179.9 406.5
1 0235 32 0. .0 403.5* 1 1055132 450. 189.1 406.6* 1 1915 232 247. 179.8 406.5
1 0240 33 0. .0 403.5* 1 1100133 446. 188.9 406.6* 1 1920 233 247. 179.7 406.5
1 0245 34 0. .0 403.5* 1 1105134 442. 188.8 406.6* 1 1925 234 247. 179.6 406.5
1 0250 35 0. .1 403.5* 1 1110135 438. 188.6 406.6* 1 1930 235 247. 179.5 406.5
1 0255 36 0. .1 403.5* 1 1115136 433. 188.4 406.6* 1 1935 236 247. 179.4 406.5
1 0300 37 0. .2 403.5* 1 1120137 427. 1883 406.6* 1 1940 237 246. 1793 406.5
1 0305 38 0. 3 403.5* 1 1125138 422. 188.1 406.6* 1 1945 238 246. 179.2 406.5
1 031039 0. A 403.5* 1 1130139 417. 197.9 406.6* 1 1950 239 246. 179.1 406.5
1 0315 40 0. .5 403.5* 1 1135140 412. 187.7 406.6* 1 1955 240 246. 179.0 406.5
1 032041 0. .6 403.5* 1 1140141 408. 197.6 406.6* 1 2000 241 246. 179.0 406.5
1 0325 42 0. .8 403.5* 1 1145142 406. 187.5 406.6* 1 2005 242 246. 178.9 406.4
1 0330 43 0. 1.0 403.5* 1 1150143 404. 187.4 406.6* 1 2010 243 246. 178.8 406.4
1 0335 44 0. 1.2 403.5* 1 1155144 403. 187A 406.6* 1 2015 244 246. 178.7 406.4
1 0340 45 0. 1A 403.5* 1 1200145 403. 187.4 406.6* 1 2020 245 246. 178.6 406.4
1 0345 46 0. 1.7 403.5* 1 1205146 402. 187.3 406.6* 1 2025 246 245. 178.6 406.4
1 0350 47 0. 2.0 403.5' 1 1210147 400. 1873 406.6' 1 2030 247 245. 178.5 406.4
1 0355 48 0. 23 403.5' 1 1215148 399. 1873 406.6' 1 2035248 245. 178.4 406.4
1 0400 49 0. 2.7 403.5' 1 1220149 398. 187.2 406.6' 1 2040 249 245. 178.3 406.4
1 0405 50 0. 3.1 403.6' 1 1225150 396. 197.2 406.6' 1 2045250 245. 1783 406.4
1 0410 51 0. 3.5 403.6' 1 1230151 396. 187.1 406.6' 1 2050 251 245. 178.2 406.4
1 0415 52 0. 4.0 403.6' 1 1235152 395. 187.1 406.6' 1 2055 252 245. 178.1 406.4
1 0420 53 0. 4.6 403.6' 1 1240153 396. 187.1 406.6. 1 2100 253 245. 178.0 406.4
1 0425 54 0. 5.2 403.6' 1 1245154 395. 187.1 406.6' 1 2105 254 245. 178.0 406A
1 04M 55 0. 5.8 403.6' 1 1250155 391. 197.0 406.6' 1 2110 255 245. 177.9 406.4
1 0435 56 0. 6.5 403.6' 1 1255156 387. 186.8 406.6' 1 2115 256 245. 177.8 406.4
1 0440 57 0. 7.2 403.6' 1 1300157 381. 186.6 406.6' 1 2120257 244. 177.8 406.4
1 0445 58 0. 7.9 403.6' 1 1305158 376. 186.4 406.6' 1 2125 258 244. 177.7 406.4
1 0450 59 0. 8.7 403.6' 1 1310159 370. 186.2 406.6. 1 2130 259 244. 177.6 406.4
1 0455 60 0. 9.6 403.7' 1 1315160 364. 186.0 406.6' 1 2135 260 244. 177.6 406.4
1 05W 61 0. 10.5 403.7. 1 1320161 358. 185.8 406.6. 1 2140 261 244. 177.5 406.4
1 0505 62 0. 11.5 403.7' 1 1325162 352. 195.6 406.6' 1 2145 262 244. 177.5 406.4
1 0510 63 0. 12.6 403.7' 1 1330163 347. 185.4 406.6' 1 2150 263 244. 177.4 406.4
1 0515 64 0. 13.7 403.7. 1 1335164 343. 185.3 406.6' 1 2155 264 244. 1773 406.4
1 0520 65 0. 14.9 403.7' 1 1340165 340. 195.2 406.6. 1 2200 265 244. 1773 406.4
1 0525 66 0. 16.1 403.8' 1 1345166 338. 185.1 406.6' 1 2205 266 244. 177.2 406.4
1 05M 67 0. 17.4 403.8' 1 1350167 336. 195.0 406.6' 1 2210267 244. 177.2 406.4
1 0535 68 0. 18.7 403.8' 1 1355168 334. 195.0 406.5' 1 2215 268 244. 177.1 406.4
1 0540 69 0. 20.0 403.8. 1 1400169 332, 184.9 406.5' 1 2220269 244. 177.1 406.4
1 0545 70 0. 21.4 403.9' 1 1405170 330. 184.8 406.5. 1 2225 270 243. 177.0 406.4
1 0550 71 0. 22.9 403.9' 1 1410171 328. 194.8 406.5' 1 2230 271 243. 177.0 406.4
1 0555 72 0. 24.4 403.9' 1 1415172 327. 194.7 406.5' 1 2235 272 243. 176.9 406.4
1 0600 73 0. 26.1 403.9' 1 1420173 326. 184.7 406.5' 1 2240 273 243. 176.9 406.4
1 0605 74 0. 27.8 404.0' 1 1425174 326. 184.7 406.5' 1 2245274 243. 176.8 406.4
1 0610 75 0. 29.5 404.0' 1 1430175 324. 184.6 406.5' 1 2250275 243. 176.8 406.4
1 0615 76 0. 31A 404.0. 1 1435176 323. 184.6 406.5. 1 2255276 243. 176.7 406.4
1 0620 77 0. 33.2 404.0' 1 1440177 322. 184.5 406.5. 1 2300 277 243. 176.7 406.4
1 0625 78 0. 35.1 404.1' 1 1445178 321. 194.5 406.5' 1 2305 278 243. 176.7 406A
1 0630 79 0. 37.1 404.1. 1 1450179 319. 184.4 406.5' 1 2310 279 243. 176.6 406.4
1 0635 80 0. 39.1 404.1' 1 1455180 317. 184.4 406.5' 1 2315 280 243. 176.6 406.4
1 0640 81 0. 41.2 404.2' 1 1500181 314. 1843 406.5' 1 2320 281 243. 176.5 406A
1 0645 82 0. 43.4 404.2' 1 1505182 312. 184.2 406.5' 1 2325 282 243. 176.5 406A
1 0650 83 0. 45.8 404.3' 1 1510183 309. 184.1 406.5' 1 2330283 243. 176.5 406A
1 0655 94 0. 48.4 4043' 1 1515184 306. 184.0 406.5. 1 2335 284 243. 176A 406A
1 0700 95 0. 51.1 4043' 1 1520185 303. 183.9 406.5' 1 2340 285 243. 176A 406.4
1 0705 86 0. 54.0 404.4. 1 1525186 301. 183.8 406.5' 1 2345 286 243. 1763 406.4
1 071097 0. 57.0 404.4' 1 1530197 298. 183.7 406.5' 1 2350 287 243. 1763 406.4
1 0715 88 0. 603 404.5' 1 1535188 297. 183.6 406.5' 1 2355 288 242. 176.3 406A
1 0720 89 S. 63.8 404.5. 1 1540189 295. 183.6 406.5. 2 0000 289 242. 176.2 406.4
1 0725 90 18. 67.5 404.6. 1 1545190 293. 183.5 4065' 2 0005290 242. 176.0 406.4
1 073091 30. 71.5 404.7' 1 1550191 292. 183.5 406.5' 2 0010 291 242 175.5 406A
1 0735 92 43. 76.2 404.8. 1 1555192 291. 183.5 406.5' 2 0015 292 241. 174.9 406A
1 0740 93 59. 81.8 404.8. 1 1600193 290. 183.4 406.5. 2 0020 293 240. 174.0 406A
1 0745 94 78. 88.6 405.0' 1 1605194 290. 183A 406.5. 2 0025 294 238. 173.0 406A
1 0750 95 101. 96.7 405.1' 1 1610195 289. 183A 406.5 2 0030 295 237. 171.9 406.3
1 0755 96 126. 105.5 405.2' 1 1615196 288. 183A 406.5. 2 0035 296 235. 170.6 4063
1 08W 97 151. 1143 405A* 1 1620197 288. 1833 406.5' 2 0040 297 233. 1693 4063
1 0805 98 172. 122.6 405.5. 1 1625198 288. 1833 406.5' 2 0045 298 231. 167.9 4063
1 0810 99 182. 1303 405.7' 1 1630199 298. 1833 406.5' 2 0050 299 230. 166.5 406.2
1 0815100 191. 1373 405.8. 1 1635 200 287. 1833 406.5' 2 0055 300 228. 165.0 406.2
PEAK FLOW TIME MAXIMUM AVERAGE FLOW
6-HR 24-HR 72-HR 24.92-HR
+ (CFS) (HR)
(CFS)
+ 456. 10.67 382. 211. 203. 203.
(INCHES) .719 1.587 1.587 1.587
(AGFT) 189. 418. 418. 418.
PEAK STORAGE TIME MAXIMUM AVERAGE STORAGE
6-HR 24-HR 72-HR 24.92-HR
+ (AC-FT) (HR)
189. 10.67 187. 133. 128. 128.
PEAK STAGE TIME MAXIMUM AVERAGE STAGE
6-HR 24-HR 72-HR 24.92-HR
+ (FEET) (HR)
406.62 10.67 406.58 405.69 405.61 405.61
CUMULATIVE AREA= 4.94 SQ MI
1
RUNOFF SUMMARY
FLOW IN CUBIC FEET PER SECOND
TIME IN HOURS, AREA IN SQUARE MILES
PEAK TIME OF AVERAGE FLOW FOR MAXIMUM PERIOD BASIN MAXIMUM TIME OF
OPERATION STATION FLOW PEAK AREA STAGE MAX STAGE
+ 6-HOUR 24-HOUR 72-HOUR
HYDROGRAPH AT
+ SUBB12 523. 8.00 216. 109. 105. 2.00
ROUTED TO
+ RTB12 523. 8.08 216. 109. 105. 2.00
HYDROGRAPH AT
+ SUBB15 253. 8.00 97. 49. 47. .77
HYDROGRAPH AT
+ SUBB13 547. 7.75 165. 82. 79. 1.27
ROUTED TO
+ RTB13 547. 7.83 165. 82. 79. 1.27
HYDROGRAPH AT
+ SUBB14 81. 7.75 24. 12. 12. .18
HYDROGRAPH AT
+ SUBNEW 175. 8.25 82. 41. 40. .71
5 COMBINED AT
+ COM1 1418. 7.92 582. 294. 283. 4.94
ROUTED TO
+ DPOND 456. 10.67 382. 211. 203. 4.94
+ 406.62 10.67
HYDROGRAPH AT
+ SUBB10 391. 7.83 133. 67. 64. 1.01
2 COMBINED AT
+ COM2 555. 10.58 468. 277. 267. 5.95
ROUTED TO
+ RTB10 555. 10.67 468. 276. 266. 5.95
HYDROGRAPH AT
+ SUBB9 95. 7.75 30. 15. 14. .23
HYDROGRAPH AT
+ SUBB8 246. 7,83 82. 41. 39. .62
HYDROGRAPH AT
+ SUBB7 245. 7.83 82. 41. 40. .63
HYDROGRAPH AT
+ SUBB6 391. 7.93 126. 63. 61. .96
5 COMBINED AT
+ COM3 1413. 7.83 762- 436. 420. 8.38
HYDROGRAPH AT
+ SUBB5 248. 7.67 59. 30. 29. .37
HYDROGRAPH AT
+ SUBB4 189. 7.75 53. 27. 26. .34
HYDROGRAPH AT
+ SUBB3 212. 7.75 61. 31. 30. .40
HYDROGRAPH AT
+ SUBB2 387. 7.75 110. 57. 54. .69
5 COMBINED AT
+ COM4 2245. 7.75 1022. 582. 561. 10.18
HYDROGRAPH AT
+ SUBBI 176. 7.83 57. 29. 28. .37
HYDROGRAPH AT
+ SUBBO 11. 8.33 6. 3. 3. .06
3 COMBINED AT
+ COM5 2425. 7.83 1083. 614. 591. 10.61
"'NORMAL END OF HEC-1-
Hydrologic/Hydraulic Modelling Input Data and Results
Future Land Use Analysis for Alternative 1 B, Conveyance:
Anacortes Avenue NE Bypass with Trunk Storm Drain Reach
Replacements
Input Data
• Basin Summary for Revised Subbasins*
*For all other input data, reference Alternative 1B
1/ 9/96 Ch2M Hill - Bellevue , WA page 1
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
FUTURE LAND USE for Alternative 1B: Bypass
BASIN SUMMARY
BASIN ID: B12 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 12 . 78 Acres BASEFLOWS : 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 5 . 11 Acres
TIME INTERVAL. . . . . 10 . 00 min CN. . . . . 86 . 00
TIME OF CONC. . . . . : 19 . 00 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 7 . 67 Acres
CN. . . . . 98 . 00
TcReach - Sheet L: 150 . 00 ns: 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Channel L: 875 . 00 kc : 42 . 00 s : 0 . 0350
PEAK RATE: 10 . 57 cfs VOL: 3 . 32 Ac-ft TIME: 480 min
BASIN ID: B15 NAME: 100 YR PRECIP
TOTAL AREA. . . . . . . : 4 . 96 Acres BASEFLOWS: 0 . 00 cfs
RAINFALL TYPE. . . . : USER1 PERVIOUS AREA
PRECIPITATION. . . . : 3 . 90 inches AREA. . : 1 . 04 Acres
TIME INTERVAL. . . . . 10 . 00 min CN. . . . . 86 . 00
TIME OF CONC. . . . . : 18 . 97 min IMPERVIOUS AREA
ABSTRACTION COEFF: 0 . 20 AREA. . : 3 . 92 Acres
CN. . . . . 93 . 00
TcReach - Sheet L: 150 . 00 ns : 0 . 1500 p2yr: 2 . 00 s : 0 . 0200
TcReach - Channel L: 650 . 00 kc : 42 . 00 s : 0 . 0200
PEAK RATE: 3 . 89 cfs VOL: 1 . 22 Ac-ft TIME: 480 min
Revised Subbasins for Future Land Use Evaluation.
All other subbasins remain unchanged.
Results
• Hydrograph Summary
• History of Hydrograph Activity
1/ 9/96 Ch2M Hill - Bellevue, WA page 2
City of Renton: NE 10th Street/Anacortes Court NE
Storm System Improvement Project
FUTURE LAND USE for Alternative 1B: Bypass
HYDROGRAPH SUMMARY
PEAK TIME VOLUME
HYD RUNOFF OF OF Contrib
NUM RATE PEAK HYDRO Area
cfs min. cf\AcFt Acres
1 19 . 854 480 285100 c f 60 . 83 2-Year Design Storm
2 33 . 237 480 468571 c f 60 . 83 10-Year Design Storm
3 40 . 760 480 573122 c f 60 . 83 25-Year Design Storm
4 48 . 293 480 678777 c f 60 . 83 100-Year Design Storm
Hydrograph Results for Future Land Use Evaluation
1/ 9/96 Ch2M Hill - Bellevue, WA page 3
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
FUTURE LAND USE for Alternative 1B: Bypass
---------------------------------------------------------------------
---------------------------------------------------------------------
HISTORY OF HYDROGRAPH ACTIVITY
Date of Session: 1/ 9/96
CLEARHIS
ZERO 1 20
REMARK *****rr*************t********t***r***r****t**********r*******txr***
START OUT BY ROUTING THE 2 YEAR STORM THROUGH HYDROGRAPH 1
LSTEND ***r*t****x►****r* ************r*k*r*rt********************r**** **
CHANGE "2 YR STORM" 2.00 PRECIP
BO B1 B10 B12 B14 B15
B3 B5 B6 B7 B9
LSTEND
ROUTE HYDROGRAPH 1 THROUGH REACH n1
Network n3
Reach <AREA> <Act Q> <Q FuLL> % Full Ndepth <Diam> <NVeL> <FVel> Carea
p3 9.31 2.64 21.52 12.29 18.11 24.00 4.42 6.37 B14
Network n2
Reach <AREA> <Act Q> <Q FuLL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p5 5.44 1.54 7.71 20.02 12.33 18.00 3.24 4.06 B9
Network n1
Reach <AREA> <Act Q> <Q FuLL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p1 12.78 4.41 7.44 59.35 5.03 12.00 9.33 8.80 B12
p2 17.74 5.93 12.27 48.35 9.21 18.00 6.52 6.45 B15
p10 27.05 8.58 21.39 40.09 16.23 30.00 3.90 4.05
p11 33.53 10.37 21.41 48.41 15.36 30.00 4.10 4.06 B10
p12 37.53 11.49 27.10 42.40 15.78 30.00 5.01 5.13 87
p6 46.97 14.16 57.54 24.61 10.54 30.00 9.20 10.90 B7
p7 51.54 16.01 77.15 20.76 9.63 30.00 11.77 14.61 B5
p8 58.44 18.91 107.04 17.66 10.63 36.00 10.83 14.08 B3
p9 60.83 19.85 90.37 21.97 11.91 36.00 9.73 11.88 B1
p13 60.83 19.85 48.56 40.88 19.29 36.00 6.18 6.39
HGRADE hgradel
n1
n2
n3
SUBMERGED 389.08
LSTEND
HGLINE hgradel
1/ 9/96 Ch2M Hill - Bellevue , WA page 4
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
FUTURE LAND USE for Alternative 1B: Bypass
---------------------------------------------------------------------
---------------------------------------------------------------------
HISTORY OF HYDROGRAPH ACTIVITY
Hydraulic Gradeline for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent_HGL EntLoss ExtLoss OutLet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
junction 389.08
mh10 junction 19.85 1.11 388.90 0.06 0.12 389.08 389.13 0.12 0.16 0.00 389.18 394.85
mh9 mh10 19.85 5.81 tw & do <dc: Inlet CtrL Assumed 390.43 0.11 0.15 0.00 390.47 395.58
mh8 mh9 18.91 15.89 tw & do <dc: Inlet CtrL Assumed 395.22 0.17 0.00 0.02 395.08 399.82
mh7 mh8 16.01 32.82 tw & do <dc: Inlet CtrL Assumed 398.43 0.13 0.00 0.01 398.31 404.81
mh6 mh7 14.16 46.48 tw & do <dc: Inlet CtrL Assumed 401.95 0.09 0.11 0.01 401.99 411.92
mhC mh6 11.49 26.46 404.21 0.04 0.09 404.34 403.68 0.07 0.09 0.01 404.37 416.08
mhB mhC 10.37 1.09 405.28 0.03 0.07 405.38 404.55 0.05 0.00 0.01 405.34 409.29
mhA mhB 8.58 0.81 406.02 0.02 0.05 406.09 405.38 0.17 0.23 0.05 406.20 410.74
mh2 mhA 5.93 0.59 407.80 0.09 0.17 408.07 407.69 0.49 0.00 0.12 407.70 412.47
mh1 mh2 4.41 52.43 tw & do <dc: Inlet CtrL Assumed 428.02 0.00 0.00 0.00 428.02 437.82
mh6 402.86
mh5 mh6 1.54 0.11 403.88 0.01 0.01 403.90 403.70 0.00 0.00 0.00 403.90 413.58
mhA 406.51
mh3 mhA 2.64 0.03 407.04 0.01 0.01 407.06 406.87 0.00 0.00 0.00 407.06 409.88
REMARK
ROUTING THE 10 YEAR STORM THROUGH HYDROGRAPH 2
LSTEND
CHANGE "10 YR STORM" 2.90 PRECIP
BO B1 B10 B12 B14 B15
B3 B5 B6 B7 B9
LSTEND
ROUTE HYDROGRAPH 2 THROUGH REACH n1
Network n3
Reach <AREA> <Act Q> <Q FULL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p3 9.31 4.75 21.52 22.09 16.04 24.00 5.22 6.37 B14
Network n2
Reach <AREA> <Act Q> <Q FuL U % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p5 5.44 2.73 7.71 35.39 10.30 18.00 3.78 4.06 B9
Network n1
Reach <AREA> <Act Q> <Q FuLL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p1 12.78 7.33 7.44 98.51 1.34 12.00 9.93 8.80 B12
p2 17.74 9.96 12.27 81.17 13.02 18.00 7.27 6.45 B15
p10 27.05 14.64 21.39 68.45 19.14 30.00 4.43 4.05
1/ 9/96 Ch2M Hill - Bellevue, WA page 5
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
FUTURE LAND USE for Alternative 1B: Bypass
---------------------------------------------------------------------
---------------------------------------------------------------------
HISTORY OF HYDROGRAPH ACTIVITY
p11 33.53 17.81 21.41 83.17 22.14 30.00 4.59 4.06 B10
p12 37.53 19.80 27.10 73.07 20.04 30.00 5.68 5.13 B7
p6 46.97 24.53 57.54 42.62 14.26 30.00 10.66 10.90 B7
p7 51.54 27.35 77.15 35.45 12.85 30.00 13.62 14.61 B5
p8 58.44 31.75 107.04 29.66 13.98 36.00 12.51 14.08 B3
p9 60.83 33.24 90.37 36.78 15.74 36.00 11.19 11.88 B1
p13 60.83 33.24 48.56 68.44 22.97 36.00 6.98 6.39
HGRADE hgradet
n1
n2
n3
SUBMERGED 389.58
LSTEND
HGLINE hgradel
Hydraulic Gradeline for Reach hgradet
<-FROM-> <--TO--> <FLOW> floss Ent_HGL EntLoss ExtLoss OutLet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
junction 389.58
mh10 junction 33.24 0.72 389.91 0.17 0.34 390.42 389.45 0.34 0.46 0.00 390.54 394.85
mh9 mh10 33.24 0.30 390.20 0.17 0.34 390.71 390.74 0.31 0.42 0.01 390.86 395.58
mh8 mh9 31.75 7.28 tw & do <dc: Inlet CtrL Assumed 395.51 0.48 0.01 0.06 395.10 399.82
mh7 mh8 27.35 85.72 tw & do <dc: Inlet CtrL Assumed 398.96 0.39 0.01 0.04 398.61 404.81
mh6 mh7 24.53 18.62 tw & do <dc: Inlet CtrL Assumed 402.31 0.25 0.33 0.05 402.43 411.92
mhC mh6 19.80 8.79 404.77 0.13 0.25 405.15 403.92 0.20 0.27 0.02 405.23 416.08
mhB mhC 17.81 0.65 405.89 0.10 0.20 406.20 404.75 0.14 0.00 0.02 406.09 409.29
mhA mhB 14.64 0.42 406.51 0.07 0.14 406.72 405.53 0.49 0.66 0.16 407.04 410.74
mh2 mhA 9.96 1.68 408.72 0.25 0.49 409.46 409.43 1.35 0.01 0.34 408.46 412.47
mh1 mh2 7.33 21.16 429.62 0.68 1.35 431.64 430.23 0.00 0.00 0.00 431.64 437.82
mh6 402.69
mh5 mh6 2.73 0.60 404.02 0.02 0.04 404.08 403.77 0.00 0.00 0.00 404.08 413.58
mhA 407.04
mh3 mhA 4.75 0.09 407.13 0.02 0.04 407.18 406.96 0.00 0.00 0.00 407.18 409.88
REMARK
ROUTING THE 25 YEAR STORM THROUGH HYDROGRAPH 3
LSTEND
CHANGE "25 YR STORM" 3.40 PRECIP
BO B1 B10 B12 B14 B15
B3 B5 B6 B7 B9
LSTEND
ROUTE HYDROGRAPH 3 THROUGH REACH n1
Network n3
Reach <AREA> <Act Q> <Q FuLL> % Full Ndepth <Diam> <NVet> <FVeL> Carea
1/ 9/96 Ch2M Hill - Bellevue, WA page 6
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
FUTURE LAND USE for Alternative 1B: Bypass
HISTORY OF HYDROGRAPH ACTIVITY
p3 9.31 5.97 21.52 27.72 15.02 24.00 5.56 6.37 B14
Network n2
Reach <AREA> <Act Q> <Q FULL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p5 5.44 3.40 7.71 44.13 9.27 18.00 4.01 4.06 B9
Network n1
Reach <AREA> <Act Q> <Q FuLL> % Full Ndepth <Diam> <NVet> <FVeL> Carea
p1 12.78 8.95 --------Pressure Flow-------- 11.40 B12
p2 17.74 12.21 12.27 99.56 16.42 18.00 7.22 6.45 B15
p10 27.05 18.06 21.39 84.42 22.42 30.00 4.59 4.05
p11 33.53 22.01 --------Pressure Flow-------- 4.48 B10
p12 37.53 24.50 27.10 90.38 23.87 30.00 5.85 5.13 B7
p6 46.97 30.39 57.54 52.81 13.81 30.00 11.24 10.90 B7
p7 51.54 33.74 77.15 43.74 14.48 30.00 14.39 14.61 B5
p8 58.44 38.98 107.04 36.41 15.65 36.00 13.22 14.08 B3
p9 60.83 40.76 90.37 45.11 17.69 36.00 11.80 11.88 B1
p13 60.83 40.76 48.56 83.94 26.77 36.00 7.23 6.39
HGRADE hgradel
n1
n2
n3
SUBMERGED 391.08
LSTEND
HGLINE hgradel
Hydraulic GradeLine for Reach hgradel
<-FROM-> <--TO--> <FLOW> floss Ent_HGL EntLoss ExtLoss Outlet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
junction 391.08
mh10 junction 40.76 0.27 391.35 0.26 0.52 392.12 389.68 0.52 0.69 0.00 392.29 394.85
mh9 mh10 40.76 0.28 392.58 0.26 0.52 393.35 390.98 0.47 0.63 0.02 393.53 395.58
mh8 mh9 38.98 0.72 394.25 0.24 0.47 394.96 395.73 0.73 0.01 0.09 395.09 399.82
mh7 mh8 33.74 134.43 tw & do <dc: Inlet CtrL Assumed 401.28 0.60 0.01 0.05 400.75 404.81
mh6 mh7 30.39 1.12 401.87 0.30 0.60 402.76 404.22 0.39 0.50 0.07 404.41 411.92
mhC mh6 24.50 1.59 406.00 0.19 0.39 406.58 404.10 0.31 0.42 0.03 406.71 416.08
mhB mhC 22.01 0.98 407.69 0.16 0.31 408.15 404.90 0.21 0.00 0.03 407.98 409.29
mhA mhB 18.06 0.46 408.44 0.11 0.21 408.76 405.63 0.74 0.99 0.24 409.24 410.74
mh2 mhA 12.21 2.52 411.77 0.37 0.74 412.88 410.07 2.02 0.02 0.52 411.40 412.47
mh1 mh2 8.95 31.58 442.98 1.01 2.02 446.00 431.94 0.00 0.00 0.00 437.92* 437.82
mh6 404.41
mh5 mh6 3.40 0.37 404.77 0.03 0.06 404.86 403.81 0.00 0.00 0.00 404.86 413.58
1/ 9/96 Ch2M Hill - Bellevue, WA page 7
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
FUTURE LAND USE for Alternative 1B: Bypass
---------------------------------------------------------------------
---------------------------------------------------------------------
HISTORY OF HYDROGRAPH ACTIVITY
mhA 409.24
mh3 mhA 5.97 0.14 409.38 0.03 0.06 409.47 407.00 0.00 0.00 0.00 409.47 409.88
REMARK
ROUTING THE 100 YEAR STORM THROUGH HYDROGRAPH 4
LSTEND
CHANGE "100 YR PRECIP" 3.90 PRECIP
BO B1 B10 B12 B14 B15
B3 B5 B6 B7 B9
LSTEND
ROUTE HYDROGRAPH 4 THROUGH REACH n1
Network n3
Reach <AREA> <Act Q> <Q FULL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p3 9.31 7.19 21.52 33.39 14.06 24.00 5.84 6.37 B14
Network n2
Reach <AREA> <Act Q> <Q FULL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p5 5.44 4.08 7.71 52.92 9.73 18.00 4.19 4.06 B9
Network n1
Reach <AREA> <Act Q> <Q FuLL> % Full Ndepth <Diam> <NVeL> <FVeL> Carea
p1 12.78 10.57 --------Pressure Flow-------- 13.46 B12
p2 17.74 14.46 --------Pressure Flow-------- 8.19 B15
p10 27.05 21.48 --------Pressure Flow-------- 4.38
p11 33.53 26.22 --------Pressure Flow-------- 5.34 B10
p12 37.53 29.20 --------Pressure Flow-------- 5.95 B7
p6 46.97 36.26 57.54 63.02 11.89 30.00 11.71 10.90 B7
p7 51.54 40.15 77.15 52.04 13.95 30.00 15.02 14.61 B5
p8 58.44 46.22 107.04 43.17 17.24 36.00 13.82 14.08 B3
p9 60.83 48.29 90.37 53.44 16.43 36.00 12.30 11.88 B1
p13 60.83 48.29 48.56 99.45 32.73 36.00 7.16 6.39
HGRADE_hgradel
n1
n2
n3
SUBMERGED 391.58
LSTEND
HGLINE hgradel
Hydraulic Gradeline for Reach hgradel
1/ 9/96 Ch2M Hill - Bellevue, WA page 8
City of Renton: NE loth Street/Anacortes Court NE
Storm System Improvement Project
FUTURE LAND USE for Alternative 1B: Bypass
HISTORY OF HYDROGRAPH ACTIVITY
<-FROM-> <--TO--> <FLOW> floss Ent_HGL EntLoss ExtLoss Outlet Inlet AppHead BndHead JunHead HeadWtr -cb/mh-
junction 391.58
mh10 junction 48.29 0.38 391.96 0.36 0.72 393.04 392.05 0.72 0.96 0.00 393.28 394.85
mh9 mh10 48.29 0.40 393.68 0.36 0.72 394.77 393.35 0.66 0.88 0.02 395.02 395.58
mh8 mh9 46.22 1.02 396.03 0.33 0.66 397.03 397.31 1.04 0.01 0.12 396.40 399.82
mh7 mh8 40.15 1.37 tw & do <dc: Inlet CtrL Assumed 402.07 0.85 0.01 0.07 401.30 404.81
mh6 mh7 36.26 1.59 402.89 0.42 0.85 404.17 405.15 0.55 0.72 0.10 405.42 411.92
mhC mh6 29.20 2.26 407.67 0.27 0.55 408.50 405.37 0.44 0.59 0.04 408.68 416.08
mhB mhC 26.22 1.39 410.07 0.22 0.44 410.74 405.08 0.30 0.00 0.05 409.39* 409.29
mhA mhB 21.48 0.65 410.04 0.15 0.30 410.49 405.75 1.04 1.38 0.34 410.84* 410.74
mh2 mhA 14.46 3.54 414.38 0.52 1.04 415.94 410.83 2.81 0.02 0.73 412.57* 412.47
mh1 mh2 10.57 44.06 456.63 1.41 2.81 460.85 433.98 0.00 0.00 0.00 437.92* 437.82
mh6
405.42
mh5 mh6 4.08 0.52 405.94 0.04 0.08 406.07 403.84 0.00 0.00 0.00 406.07 413.58
mhA
410.84
mh3 mhA 7.19 0.20 411.04 0.04 0.08 411.16 407.04 0.00 0.00 0.00 409.98* 409.88
End program file BASIN O.PGM
Appendix C
Cost Estimates
NE 10th Street/Anacortes Court Stormwater Drainage Improvement Project
City of Renton
116868A0.30
August 24,1996
T.Ptatin
TABLE C-1: ORDER OF MAGNITUDE COST ESTIMATES FOR ALTERNATIVES ANALYSIS
Alternative 1B PI Improvements
Order-of-
Existing RCP Pipe Surface Magnitude
Diameter Replacement Maximum Average Length of Surface Placement Restoration Trench Box Cost
Pipe Reach Q n Diameter in Depth ft De th ft Reach fl Type Cost(SAf) Cost($/") SM) Estimate
BYPASS
mh2-A 18 6 6 225 Road 60 1 20 2 18,450
mhA-B 30 6 5 280 1 Road 80 20 2 28,560
mhB-C 30 13 9 400 Road 80 20 2 40,800
mhC-14.C3-13 30 13 12 300 Road 80 20 2 30,600
14.C3-13-mh6 30 13 12 225 Road 80 20 2 22,950
mh3-A 24 6 5 235 Road 65 20 2 20,445
UPGRADE
mhl-14.D4-2 12 18 12 9 305 Road 60 20 2 25,010
14.D4-2-mh2 12 18 6 5 295 Road 60 20 2 24,190
mh5-6 18 no change n/a n/a 410 - - - -
mh6-14.C3-11 18 30' 1 11 9 180 Road 80 20 2 18,360
14.C3-11-mh7 18 30' 7 7 60 Road 80 20 2 6,120
mh7-8 18 30' 7 6 120 Road 80 20 2 12,240
mh8-9 18 36' 6 6 255 Road 90 20 2 28,560
mh9-10 24 36' 6 6 60 Road 90 20 2 6,720
si hon 12 2 pipes) 36 6 6 30 Road 90 20 2 3,360
o arch 24 36 6 6 85 Road 90 20 1 2 9,520
SUBTOTAL= 295,885
'When denoted by an asterisk,the replacement diameter was determined 20%Contingency= 59,177
using the Inlet Control Nomograph,otherwise,it was calculated using 10`Yo Undefined= 29,589
Mannings Equation. 10%General Condit.= 29,589
SUBTOTAL= 414,239
8.5%Sales Tax= 35,210
PIPING TOTAL= 449,449
Alternative 1B Structure Items
Largest
Connected Calculated Standard Order-of-
Pipe Manhole Manhole Magnitude
Diameter Additional 24" Diameter Diameter Depth Material Cost
Manhole ID m or 36' (ft) (ft Depth ft Class Cost S/ea Estimate($
mh1 proposed does not change existing size 12 C no replacement
14.D4-2 proporsed does not change existing size 7 B no replacement
mh2 proposed does not change xistinq size 6 B no replacement
mhA 30 36 66 72 6 B 5,000 1 5,000
mh3 24 36 60 60 5 A no replacement
mhB 30 36 66 72 6 B 5,000 5,000
mhD 30 24 54 60 10 B 5,900 5,900
mhC 30 36 66 72 14 C 8,400 8,400
14.C3-13 30 24 54 60 12 C 6,600 6,600
mh6 30 36 66 72 11 B 7,200 7,200
14.C3-11 30 36 66 72 7 B 5,400 5,400
mh7 30 36 66 72 8 B 5,900 5,900
mh8 36 36 72 72 6 B 5,000 5,000
mh9 36 24 50 60 6 B 4,400 4,400
mhSi hon 36 24 60 60 7 B 4,800 4,800
Arch Junction-
SUBTOTAL= 70,600
Sizing Rules of Thumb: 24'added to largest dia. 20%Contingency- 14,120
and 12'more added for bends in line. 10%Undefined- 7,060
10%General Condit. 7,060
Depth Class: A<6;B=6-12';C>12' SUBTOTAL= 98,840
8.5%Sales Tax= 8,401
16 cu.yd.concrete a$400/cu.yd. IMANHOLESTOTAL= 107,241
(includes rebar,construction crew and formwork)
ALT. 1B PROJECT TOTAL = $ 556,691
NE 10th Street I Anacortes Court Stormwater Drainage Improvement Project
City of Renton
116868.A0.30
August 24,1M(Updated 1117/96)
T.Platin
TABLE C-2: ORDER OF MAGNITUDE COST ESTIMATES FOR ALTERNATIVES ANALYSIS
Alternative 3A Pipe Improvements
Order-of-
Magnitude
Existing Surface Cost
Diameter Replacement Maximum Average Length of Surface Material Restoration Trench Box Estimate
Pipe Reach Q n Diameter m Depth(ft) Depth ft Reach ft Type Cost S Cost
mhl-14.D4-2 12 no change nla n/a 295 Road I n/a n/a n/a n/a
14.134-2-mh2 12 18 6 5 295 Road 60 20 2 24,190
mh3-A 12 24 6 5 240 Road 65 20 2 20,880
mhA-2 12 24 8 7 225 Road 65 20 2 19,575
mh2-Pond - 24 8 8 50 Meadow 65 2 2 3,450
mhF-B - 24 8 7 160 Lawn 65 20 2 13,920
mh4-B 18 18 8 7 215 Road 60 20 2 17,630
mhB-D - 24 10 8 200 Road 65 20 2 17,400
mhD-C 24 14 12 200 Road 65 20 2 1 17,400
mhC-E - 24 14 13 300 Road 65 20 21 26,100
mhE-6 12 24 12 1 11 230 Road 65 20 21 20,010
siphon 12 2 i 24 9 1 9 f 90 Road 65 20 21 7,830
SUBTOTAL- 188,385
'When denoted by an asterisk,the replacement diameter was determined 20%Contingency= 37,677
using the Inlet Control Nomograph,otherwise,It was calculated using 10%Undefined= 18,839
Mannings Equation. 10%General Condit.= 18,839
SUBTOTAL- 263,739
8.5%Sales Tax- 22,418
PIPING TOTAL ......... 286,157
POND EXCAVATION,Haul and Disposal-a 8800 cu. d.' $8/cu. d.R S '76 000
PROPERTY ACQUISITION Pond,maint.road&r/w through lot on'Ahacortes 100,000
$2/sq.ft.for Pond Excavation=58,000 sq.ft.
Alternative 3A Structure hems
Largest
Incoming Order-of-
Pipe Calculated Standard Magnitude
Diameter Additional 24" Manhole Manhole Depth Material Cost
Manhole ID in or 36'• Diameter ! Diameter m Depth Class" Cost $/ea Estimate S
mh1 proposed does not change existing size no replacement
14.134-2 proposed does not change existing size no replacement
mh3 proposed does not change existing size no replacement
mhA proposed does not change existing size no replacement
mho proposed does not change existing size no replacement
mh2 24 36 60 60 9 B 5,500 5,500
mhB 24 36 60 60 7 1 B 4,800 4,800
mhD 24 24 48 48 10 B 3,300 3,300
mhC 24 36 60 60 14 C 7,400 7,400
mhE proposed does not change existing size no replacement
mh9 pro does not chanue existina size no replacement
mh10 24 24 48 48 7 B 2,700 2,700
mh6 24 36 60 60 11 B 6,300 6,300
Dischar a Structure 7,000 7,000
SUBTOTAL- 37,000
Sizing Rules of Thumb: 24'added to largest dia. 20%Contingency= 7,400
and 12'more added for bends in line. 10%Undefined= 3,700
10%General Condit.= 3J2O3
"Depth Class: A<6;B=6-12;C>12' SUBTOTAL- 51
8.5%Sales Tax= 4
MANHOLESTOTAL a 66
ALT. 3A PROJECT TOTAL E 517,360
/ Section 1
Section 1
Executive Summary
This drainage plan summarizes the results of drainage system investigation, analysis, and
solutions development to resolve existing flooding problems in a tributary trunk drainage
system within the Honey Creek drainage basin, City of Renton. The drainage basin study area
consist of approximately 63 acres, and is roughly bounded on the north by Sunset Boulevard,
on the east by 138th Avenue SE, on the south by NE loth Street, and on the west by Union
Avenue NE. Solutions to existing flooding problems along the trunk drainage system are
identified, with particular focus on those improvements that will eliminate frequent flooding
within the upstream portion of that drainage system in the area of NE loth Street and
Anacortes Court NE.
The plan findings validate prior preliminary drainage system assessment work performed by
the City and documented flooding within the drainage system. It presents the alternative
improvement solutions considered to resolve those flooding problems and provide a level of
protection consistent with current City of Renton standards and design criteria.
�. A total of eight conceptual solutions were initially evaluated. Those solutions included
options for increase in size of the trunk drainage system, bypasses within the drainage
system, possible diversions to adjacent drainage systems, and surface and sub surface
detention storage. Based on review of those options with the City staff, two system-wide
improvement solutions were selected for further evaluation. Those included Alternatives 1B,
Anacortes Avenue NE Bypass Trunk Storm Drain, and Alternative 3A, NE 10th Street
Detention Pond and Reconnection with Existing Trunk System. Those solutions are
illustrated on Figures 4-1 and 4-3 in Section 4 of this report. Technical feasibility, benefits
and potential impacts, and estimated implementation costs were evaluated for each
alternative. After review of results of that assessment with City staff, Alternative I was
selected as the preferred solution for implementation.
Alternative I consists of the following drainage system improvements in order of their
recommended priority for implementation:
1-1
1. Replace the existing siphon located south of Sunset Boulevard in Whitman Court NE
P g P
with a 36-inch storm drain, and connect that pipeline to both existing Honey Creek
dual corrugated metal pipe arches (CMPAs) with a reinforced concrete junction
structure.
2. Install a new 30-inch bypass storm drain in Anacortes Avenue NE and in NE 1 lth
Street, and with connections to the existing trunk and lateral storm drainage system in
NE loth Place and NE loth Street.
3. Install the remaining 30- to 36-inch replacement trunk storm drain through the apart-
ment complexes along the north-south alignment of Whitman Court NE, and connect
to the improvements described in priority 1 and 2.
The total implementation cost (exclusive of engineering and administrative costs) for imple-
menting the selected plan project improvements is estimated to be $560,000.
The benefits provided by this improvement will be a significant increase in the level of flood
protection to the entire drainage system (from less than 2-year to a minimum of 25-year level
of protection). The potential impacts of this option include a significant (approximately 3-
fold) increase in peak design flows delivered to the downstream Honey Creek system that
could affect downstream flooding along the Honey Creek drainage system or have other
associated impacts (e.g., erosion/sedimentation, habitat degradation). Evaluation of these
potential impacts should be considered in the succeeding phases of project implementation.
1-2
Section 2
Section
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Section 5 `
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' Appendix A
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Appendix B
Appendix C
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