HomeMy WebLinkAboutSWP273334 (3)n
7
SWP-27-3334
' RENTON AVE S / S 3rd ST
STORM SYSTEM OUTFACE RELOCATION
' DRAINAGE ANALYSIS
Prepared by:
' City of Renton
Planning/ Building/ Public Works Department
Surface Water Utility
August 2006
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oilH;!l
me
10!�111.:; o
0' 500'
N ' '
Scale: 1" = 500'
Project Location
Renton Ave S / S 3rd St
Storm System Outfall Relocation
City of Renton Surface Water Utility
D. Carey 8/06
CO
0' 100'
N ' '
Scale: 1" = 100'
ROad under 1-4
05
i
i Q
/
EROSION
GULLIES
DISCHARGE
ON SLOPE
-Projec
Location
Project Location
Renton Ave S / S 3rd St
Storm System Outfall Relocation
City of Renton Surface Water Utility
D. Carey 8/06
Drainage Basin Analysis
H:\File Sys\SWP - Surface Water Projects\SWP-27 - Surface Water Projects (CIP)\27-3334 - Renton Ave Outfall\1110 Design
Calcs\060815 Hydraulic CoverPage.doc Page 1
Drainage Basin Analysis
F1
I
H:\File Sys\SWP - Surface Water Projects\SWP-27 - Surface Water Projects (CIP,\27-3334 - Renton Ave Outtall\1110 Design
' Calcs\060815 Hydraulic CoverPage.doc Page 1
11
Project: Renton Ave. S Storm System Repair D.Carey 8/11/06
Future Basin Runoff Analysis
KING COUNTY DEPARTMENT OF PUBLIC WORKS
Surface Water Management Division
HYDROGRAPH PROGRAMS
Version 4.21 B
1 - INFO ON THIS PROGRAM
2 -SBUHYD
3 - MODIFIED SBUHYD
4-ROUTE
5 - ROUTE2
6-ADDHYD
7 - BASEFLOW
8-PLOTHYD
9-DATA
10 - RDFAC
11 - RETURN TO DOS
ENTER OPTION: 2
SBUH/SCS METHOD FOR COMPUTING RUNOFF HYDROGRAPH
STORM OPTIONS:
1 - S.C.S. TYPE -IA
2 - 7-DAY DESIGN STORM
3 - STORM DATA FILE
SPECIFY STORM OPTION: 1
S.C.S. TYPE -IA RAINFALL DISTRIBUTION
ENTER: FREQ(YEAR), DURATION(HOUR), PRECIP(INCHES)
25, 24, 3.4
---------------------------------------------------------------------------------------------------------
******************** S.C.S. TYPE -IA DISTRIBUTION ********************
********* 25-YEAR 24-HOUR STORM **** 3.40" TOTAL PRECIP. *********
-----------------------------------------------------------------------------------------------------------
ENTER: A(PERV), CN(PERV), A(IMPERV), CN(IMPERV), TC FOR BASIN NO. 1
7.30, 86, 10.80, 98, 20
DATA PRINT-OUT:
AREA(ACRES) PERVIOUS IMPERVIOUS TC(MINUTES)
A CN A CN
18.1 7.3 86.0 10.8 98.0 20.0
PEAK-Q(CFS) T-PEAK(HRS) VOL(CU-FT)
10.41 7.83 176805
ENTER [d:][path]filename[.ext] FOR STORAGE OF COMPUTED HYDROGRAPH:
c:trash
Q 1 S = ) 0.4 JS
,A-w, Co. A-th 0
015 " 10.1Ctr
' H:\File Sys\SWP - SurfaceWater ProjectslSWP-27 -Surface Water Projects (CIP)127-9998 -Renton Ave 0ut1a1111110 Design
Calcs\Peak Q 25-Year.doc
Project: Renton Ave S Storm System Repair D. Carey
Final Design Revised: 8/11/06
Future Basin Characteristics
Entire Basin = 18.16 ac Assume 8 du/ac future use.
SCS Hydro soil group mainly C.
Per KCM Table 3.5.2B dor 8 du/ac use 60% imperv, assume 40% lawns, CN-V86.
Total Pervious CN Imper. CN Estimated
For Entire Basin Area (ac) Area (ac) Area (ac) Tc (min.)
18.10 7.30 86 10.80 98 20.1
Time of Concentration Calcs
Pipe Flow
L
v
tc
About 15% slope Pipe
420
5.5
1.3
Uses estimate of flow velocity, based on Manning
Nomograph.
Shallow Conc. Flow
k
L
s
v
tc
V = k Sgrt(s) , T= L/(v x 60) Gutter or roadsil
27
600
0.11
8.9549
1.1
Assume conc. gutter
27
975
0.065
6.8837
2.4
Sheet Flow
ns
L
P2
s
tc
T = {0.42x(ns x L)110.8} / Lawn
0.15
285
2.0
0.095
15.4
{( P2)110.5 x (s)^0.4 }
0.15
2.0
0.100
0.0
Short Prairie Grass and Lawns, ns=0.15
Assume flow thru 2 grass yards to street ditch/gutter
Comments:
Tc calculations per King County Manual - pp.3.5.2-5
Minimum Tc = 6.3 minutes.
File: Runoff-TC4-CN-KCM.XLS - Tab: Future-Calc
Page 1
EPP
Are = 73 00 qTn
or 91 200 sf, ,
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NORTH
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KIN-G' Ot1N`TY,"WAS`HI-NGTON SURF-AC`E�W--ATE-R DEShGN MANUAL °:
FIGURE 3.S.2A HYDROLOGIC SbIL GROUP b THi SOILS` IN IdNG COUNTY
SOIL GROUP
.,HYDROLOGIC.
GROUP'
'SOIL GROUP
HYDROLOGIC
GROUP'
Alderwood
C
Orcas Peat
D
Arents; n4erivood -Material- . _j
C
Oridla
D
Arents;; Everett Material
B
Ovall
C
Beausite
C
Pilchuck
C
Bellingham -
'
D
Puget.
D
8
Briscot
D
Puyallup
Bttcktev. ..
D
Ragnar -
B
Coastal Beaches
Variable
Renton
D
Earlmont SlIt.l=oarn
D
Riverwash
Variable
Edgewick
C
Salal
'G
Everett.
A
Sammamish
D
Indianola
Seattle'
D
lQsap.'
C
Shacar '
D
Iaaus
C
Si sat'
C
Mixed Alluvial Land
Variable
Snohomish ..
D
Neilton
A
Sultan
C
Newberg
B
Tukwila
D
Nooksack
C
Urban
Variable
Normal Sandy Loam
D
woodinville
D
HYDROLOGIC SOIL GROUP CLASSIFICATIONS
A -(Low runoff potential). Soils having high infltration rates, even when thoroughly wetted,. and consisting
chiefly'of deep, well=to-excessively drained sands or gravels:- These soils have a high rate of water:
transmission.
B. (Moderately low runoff potential). Sods having moderate infiltration rates when thoroughly wetted; and
consisting chiefly of moderately fine to moderately coarse textures. These soils have a moderate rate of
water transmission.
C. (Moderately high runoff potential). Soils having slow infiltration rates when thoroughly wetted, and ,
consisting.chiefly of soils with a layer that Impedes downward movement of water, or soils with moderately
flne.torfine textures. These. soils have a slow rate of water transmission.
D. (High runoff potential). Soils having very slow infiltration rates when thoroughly wetted and consisting
chiefly of clay soils with a high swelling potential, soils with a permanent high water table, soils with a
hardpan or day layer at or near the surface, and shallow soils over nearly impervious material. These soils
have a very slow rate of water transmission.
3.5.2-2 1/90
ING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
`ABLE 3.5.2B SCS WESTERN WASHINGTON I
SCS WESTERN WASHINGTON RUNOFF CURVE NUMBERS (Published by SCS in 1982)
Runoff curve numbers for selected agricultural, suburban and urban land use for Type 1A
rainfall distribution, 24 bourstorm duration.
CURVE NUMBERS BY
HYDROLOGIC SOIL GROUP
LAND USE DESCRIPTION
A B C D
Cultivated land(1):
winter condition
86 91 94 95
Mountain open areas:
low growing brush and grasslands
74 82 89 92
Meadow or pasture:
65 78 85' 89
Wood or forest land:
undisturbed
42-� 64 76 81
Wood or forest land:
young second .growth or brush
55 72 81 86
Orchard:
with cover crop
81 88 92 94
Open spaces, lawns, parks, golf courses, cemeteries,
landscaping.
good condition:
grass cover on 75%
or more of the area
6.8 00 86. 90
fair condition:
grass cover on 50%
to 75% of the area
77 85 90 92
Gravel roads and parking lots
76 85 89` 91
Dirt roads and parking lots
72 82 87 89
Impervious surfaces, pavement, roofs, etc.
98 98 98 98
Open water bodies:
lakes, wetlands, ponds, etc.
100 100 100 100
Single Family Residential (2)
Dwelling Unit/Gross Acre
% Impervious (3)
1.0 DU/GA
15
Separate curve number
1.5 DU/GA
20
shall be selected
2.0 DU/GA
25
for pervious and
2.5 DU/GA
30
impervious portion
3.0 DU/GA
34
of the site or basin
3.5 DU/GA
38
4.0 DU/GA
42.
4.5 DU/GA
46
5.0 DU/GA
48.
5.5 DU/GA
50
6.0 DU/GA
52
6.5 DU/GA
54
7.0 DU/GA
56
9.0 pu/%sA
G0
Planned unit developments,
% impervious
condominiums, apartments,
must be computed
commercial business and
industrial areas.
(1) For a more tletailed oescnption of agncuiturai Tana use curve numoers refer io rvailonar tngrneenng
Handbook, Section 4, Hydrology, Chapter 9, August 1972.
(2) Assumes roof and driveway runoff is directed into street/storm system.
(3) The remaining pervious areas pawn) are considered to be in good condition for these curve numbers.
3.5.2-3
1/90
S ;KI-NG CO -LINTY, WASH-I-NGTON, SUR-F-ACE-W-ATER-.DESI-GN MANUAL
,ywh
-' The area's potential maximum detention, S, is related to its curve number, CN:
S = (1000 /CN) - 10
The combination of the above equations allows for estimation of the total runoff volume by computing the
total runoff depth, ad, 9Nen the total precipitation depth, PR. For example, If the curve number of the area
is 70, then the value of S is 4.29. With a total precipitation for the design event of 2.0 Inches, the total
runoff depth would be:
' ad = (2.0 - 0.2 (4.29)12 /(2.0 + 0.8 (4.29)] = 0.24 inches
This computed runoff represents Inches
over
the tributary coversions) Therefore, the total volume of runoff is
' found by multiplying Od by the a
Total runoff
Volume = 3,630 X ad X A
' (cu-ft) (cu-ft/ac-in) (in) (ac)
If the area is 10 acres, the total runoff volume is:
' 3,630 cu. ft./acre-in. x 0.24 in. x 10 acres = 8 712 cu. ft.
When developing the runoff hydrograph, the above equation for ad is used to compute the incremental
runoff depth for each time Interval from the Incremental precipitation depth given by the design storm
' hyetograph. This time distribution of runoff depth is often referred to as the precipitation excess and
provides the basis for synthesizing the runoff hydrograph.
Travel Time and Time of Concentration for Use in Hydrograph Analysts
(based on the methods described in Chapter 3, SCS publication 210-VI-TA-55, Second Ed., June 1986)
Travel time (T) is the time it takes water to travel from one location to another In a watershed. T, is a
component of time of concentration (T j, which Is the time for runoff to travel from the hydraulically .most
distant point of the watershed. T, is computed by summing ail the travel times for consecutive
components of the drainage conveyance system. T, influences the shape and peak of the runoff
hydrograph. Urbanization usually decreases T, thereby increasing the peak discharge. But T, can be
' increased as a result of (a) ponding behind small or inadequate drainage systems, including storm drain
inlets and road culverts, or (b) reduction of land slope through grading.
Water moves through a watershed as sheet flow, shallow concentrated flow, open channel flow, or some
combination of these. The type that occurs is best determined by field inspection.
Travel time (T,) is the ratio of now length to flow velocity:
L
T1 _ V [Travel Time Equation]
where
T, = travel time (min)
' L = flow length (ft)
V = average velocity (ft/s), and
60 = conversion factor from seconds to minutes.
Time of concentration (j is the sum of T, values for the various consecutive flow segments.
T, =Tt +T, +...T,
1
35.2-5 1/90
1
�-
s' KING'COUNT_Y; WASHINGTON; SURFACE WATER.DE$IG.N,M,ANU,AL
F:
where
I
T, = time of concentration (min), and
'
m = number of flow segments
Sheet Flow: Sheet flow is flow over plane surfaces. it usually -occurs in the headwater of streams. With
sheet flow, the friction value (nj (a modified Manning's effective .roughness coefficient that includes the
effect of raindrop impact; drag over the plane surface; obstacles such as litter, crop ridges, and rocks; and
erosion and transportation of sediment) is used. These n, values are for very shallow flow depths of about
0.1 foot and are only used for travel lengths up to 300 feet. TabW3.5.2.0 gives Manning's n, values for
'
sheet flow for various surface conditions.
For sheet flow up to 300 feet, use Manning's kinematic solution to directly compute T,:
tSheet
flow: T = 0.42 (n,L)o.a
`
.5 (so) 0.4
(P2) 0.5
where
T, = travel time (min),
n, = sheet flow Manning's effective roughness coefficient (from Table 3.5.2%
L = flow length (ft),
P2 = 2-year, 24-hour rainfall (in), (see Figure 3.5.1 C) and
S. = slope of hydraulic grade line (land slope, ft/ft)
Velocity Equation
A commonly used method of computing average velocity of flow, once it has measurable depth, is the
following equation:
V=k/s—.
' where:
V = velocity (ft/s)
k = time of concentration velocity factor (ft/s)
' S. = slope of flow path (ft/ft)
Y is computed for various land covers and channel characteristics with assumptions made for hydraulic
radius using the following rearrangement of Manning's equation:
k = (1.49 (R) 0.667 )/n.
where R = an assumed hydraulic radius
n = Manning's roughness coefficient for open channel flow (from Table 4.3.713 in Chapter 4)
1
3.5.2-6
NG COUNTY, W.ASHINGTO.N, SURFACE WATER -DESIG.N MANUAL
Shallow Concentrated Flow: After a maximum of 300 feet, sheet flow is assumed to become shallow
concentrated flow. The average velocity for this flow can be calculated using the k, values from Table
3.5.2C In which average velocity is a function of watercourse slope and type of channel. After computing
the average velocity using the Velocity Equation above, the travel time (ra for the shallow concentrated
flow segment can be computed using the Travel Time Equation described above.
Open Channel Flow: Open channels are assumed to begin where surveyed cross section information
has been obtained, where channels are visible on aerial photographs, or where lines indicating streams
appear (in blue) on United States Geological Survey (USGS) quadrangle sheets. The k, values from Table
3.5.2C used in the Velocity Equation above or water surface profile information can be used to estimate
' average flow velocity. Average flow velocity is usually determined for bank -full conditions. After average
velocity is computed the travel time (r) for the channel segment can be computed using the Travel Time
Equation above.
' Lakes or Wetlands: Sometimes it is necessary to estimate the velocity of flow through a lake or wetland
at the outlet of a watershed. This travel time is normally very small and can be assumed as zero. Where
significant attenuation may occur due to storage effects, the flows should be routed using the "level pool
' routing" technique described in Section 3.5.4.
Limitations: The. following limitations apply in estimating travel time (f,).
' o Manning's kinematic solution should not be used for sheet flow longer than 300 feet.
o In watersheds with storm sewers, carefully identify the appropriate hydraulic flow path to estimate T,.
Storm sewers generally handle only a small portion of a large event. The rest of the peak flow
travels by streets, lawns, and so on, to the outlet. Consult a. standard hydraulics textbook to
determine average velocity In pipes for either pressure or nonpressure flow.
o A culvert or bridge can act as a reservoir outlet if there is significant storage behind it. A
hydrograph should be developed to this point and the "level pool routing" technique described in
Section 3.5.4 should be used to determine the outflow rating curve through the culvert or bridge.
' Example: The following is an example of travel time and time of concentration calculations.
Given: An existing drainage basin having a selected flow route composed of the following 5 segments:
(Note: Drainage basin is in Federal Way and has a P2 = 2.1 inches, from Figure 3.5.1 C.)
Segment 1: L = 200 ft, Forest with dense brush (sheet flow)
' s, 0.03..ft/ft, n, 0.80
Segment 2: L = 300 ft, Pasture (shallow concentrated flow)
so = 0.04 ft/ft, k, = 11
' Segment 3: L = 50 ft, Small pond (year around)
so=0.00ft/ft,k=0
' Segment 4: L = 300 ft, Grassed waterway, (intermittent channel)
s,=0.05,k=17
Segment 5: L.= 500 ft, Grass -lined stream (continuous)
s,=0.02,k=27
3.52-8 1/90
i COUNTY, WASH.INGTON, SURFACE WATER DESIGN MANUAL
Iculate travel_ imes (r,'s) for each reach and then sum them to calculate the drainage basin time of
__.icentration (T-1.
Segment 1: Sheet flow, Tt = 0.42 (n,L) 0
'8
(L < 300 feet) (p2)0.5 (so)°.a
T = (0.42) I(0.80)(200)] °'8 = 68 minutes
(2.1)0.5 (0.03) 0.4
Segment 2: Shallow concentrated flow V = k,
V2 = (11) (0.04) = 2.2 ft/S
T2 = L =Jao—& = 2 minutes
60V 60(2.2)
Segment 3: Flat water surface
T3 = 0 minutes
Segment 4: Intermittent channel flow
V4 (17) (0 0505 = 3.8 ft/s
T4 =L1101 = 1 minute
60(3.8)
Segment 5: Continuous stream
VS = (27) (0.02) = 3.8 ft/s
TS = 500 = 2 minutes
60(3.8)
T,=Tl+T2+T3+T4+T5
Te=68+2+0+1 +2=73minutes
It is important to note how the initial sheet flow segment's travel time dominates the time of concentration
computation. This will nearly always be the case for relatively small drainage basins and in particular for
the existing site conditions. This also illustrates the significant Impact urbanization has on the surface
runoff portion of the hydrologic process.
3.5.3 HYDROGRAPH SYNTHESIS
This section presents a description of the hydrograph methods used to synthesize the runoff hydrograph
from precipitation excess (time distribution of runoff depth) and time of concentration.
' King County the SWM Division staff have used and tested two similar hydrograph methods: the Soil
Conservation Service Unit Hydrograph (SCSUH) method and the Santa Barbara Urban Hydrograph
(SBUH) method. Both methods are based on the SCS Curve Number (CN) approach and utilize basic
' SCS equations for computing soil absorption and precipitation excess. The SCSUH method works by
converting the incremental runoff depths (precipitation excess) for a given basin and design storm Into unit
hydrographs of equal time base according to basin time of concentration and adds them to form the total
runoff hydrograph. The SBUH method, on the other hand, converts the incremental runoff depths into
1
3.5.3-1 1/90
COUNTY, WASHINGTON, SURFACE WATER
DESIGN MANUALKING
"k" USED IN TIME CALCULATIONS FOR HYDROGRAPHS
TABLE 3.5.2C
"n" AND VALUES
'n; Sheet Flow Equation Mlanning's Values (For the. initial 300 it d travel)
n.-
Smooth surfaces (concrete, asphalt. gravel, or bare hard packed Sol
O.Ot t
1
Fatlow fields or loose sdB surface (no residue)
0.05
Cultivated Sol with residue cover ( s < - 0.20 11/111)
0.06
Cultivated sop with residue cover (S> 0.20 R/h)
0.17
0.15
Short prairie grass and lawns
0.24
Dense grasses
0.41
'
Bermuda grass
0.13
Range (natural)
0.40
Woods or forest with light underbrush
Woods or forest with dense underbrush
0.80
'
*Manning values for sheet flow only. from Overton end Meadrrws 1976 (See TR-55, 1986)
V Values Used In Travel Time/Tine Of Concentration Calculations
k•
Shallow Concentrated Flow/(After the initial 300 N. of sheet now. R - 0.1)
t. Forest with heavy ground litter artd'mea], (n=0.10)
3
2. Brushy ground with some trees (n = 0.060)
5
3. Fallow or minimum tillage cultivation (n-0.040)
8
4. High grass (n - 0.035)
9
5. Short grass, pasture and lawns (n-0.030)
tt
6, Nearly bare ground (n-0.025)
13
7. Paved and gravel areas (n=0.012)
27
Channel Flow (Intermittent) (At the beginning of visible channels: R=0.2)
k.
5
1. Forested Swale with heavy ground liner (n = 0.10)
2. Forested drainage course/ravine with defAned channel bed (n=0.050)
10
'
3. Rock -lined waterway (n=0.035)
15
4. Grassed waterway (n-0.030)
17
5. Earth -lined waterway (n=0.025)
20
6. CMP pipe (n=0.024)
21
7. Concrete pipe (0.012)
42
/
8. Other waterways and pipes
Channel Flow (Continuous stream, R = 0.4) k.
g. Meandering stream with some pods (n - 0.040)
20
23
to. Rock41ned stream (n=0.035)
27
11. Grassained stream (n-0.030)
0.807/n•• IJ)
12. Other streams, man-made channels and pipe
ii
--See Chapter S. Tate 5.3.6C for additional Mannin99'n• values for open channels
3.5.2-7 I/90
KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL
TABLE 4.3.78 VALUES OF THE ROUGHNESS COEFFICIENT, "n"
Type of Channel
Manning's
Type of Channel
Manning's
and Description
"n"'
and Description
"n"*
(Normal)
(Normal)
A. Constructed Channels
6. Sluggish reaches, weedy
0.070
a. Earth, straight and uniform
deep pools
1. Clean, recently completed
0.018
7. Very weedy reaches, deep
0.100
2. Gravel, uniform section,
0.025
pools, or floodways with
clean
heavy stand'of timber and
3. With short grass, few
0.027
underbrush
weeds
b. Mountain streams, no vegetation
b. Earth, winding and sluggish
0:025
in channel, banks usually steep,
1. No vegetation
0.025
trees and brush along banks
2. Grass, some weeds
0.030
submerged at high stages
3. Dense weeds or aquatic
1. Bottom: gravel, cobbles, and
0.040
plants in deep channels
0.035
few boulders
4. Earth bottom and rubble
2. Bottom: cobbles with large
0.050
sides
0.030
boulders
5. Stony bottom and weedy
B-2 Flood plains
banks
0.035
a. Pasture, no brush
6. Cobble bottom and clean
1. Short grass
0.030
sides
0.040
2. High grass
0.035
c. Rock lined
b. .Cultivated areas
1. Smooth and uniform
0.035
1. No crop
0.030
2. Jagged and irregular
0.040
2. Mature row crops
0.035
d. Channels not maintained,
3. Mature field crops
0.040
weeds and brush uncut
c. Brush
1. Dense weeds, high as flow
1. Scattered brush, heavy
0.050
depth
0.080
weeds
2. Clean bottom, brush on
2. Light brush and trees
0.060
sides
0.050
3. Medium to dense brush
0.070
3. Same, highest stage of
4. Heavy, dense brush
0.100
flow
0.070
d. Trees
4. Dense brush, high stage
1. Dense willows, straight
0.150
B. Natural Streams
0.100
2. Cleared land with tree
0.040
B-1 Minor streams (top width at
stumps, no sprouts
flood stage < 100 ft.)
3. Same as above, but with
0.060
a. Streams on plain
heavy growth of sprouts
1. Clean, straight, full stage
4. Heavy stand of timber, a few
0.100
no rifts or deep pools
0.030
down trees, little
2. Same as above, but more
undergrowth, flood stage
stones and weeds
0.035
below branches
3. Clean, winding, some
5. Same as above, but with
0.120
pools and shoals
0.040
flood stage reaching
4. Same as above, but some
branches
weeds
0.040
5. Same as 4, but more
stones
0.050
Note, these "n" values are "normal" values for use in analysis of channels. For conservative design for
channel capacity the "maximum" values listed in other references should be considered. For channel bank
stability the minimum values should be considered.
4.3.7-7
1/90
Backwater Analysis
And
Pipe Sizing
I H:\File Sys\SWP - Surface Water Projects\SWP-27 - Surface Water Projects (CIP,127-3334 - Renton Ave Outfall\1110 Design
Calcs\060815 Hydraulic CoverPage.doc Page 2
11
Backwater Analysis
And
Pipe Sizing
H:\File Sys\SWP - Surface Water Projects\SWP-27 - Surface Water Projects (CIP,127-3334 - Renton Ave Outfall\1110 Design
' Calcs\060815 Hydraulic CoverPage.doc Page 2
IRenton Ave S / S 3rd St Storm System Repair Project
F,
D.Carey 8/18106
KING COUNTY DEPARTMENT OF NATURAL RESOURCES
Water and Land Resources Division
BACKWATER ANALYSIS PROGRAM
Version 5.30h
File Opened for Reading:pipedata2.bwp
REVIEW OF THE PIPE -DATA
PI OUTLET INLET IN OVERFLO BND STRU Q
# LENGTH DI TY ELEV ELEV TY KE K M C Y ELEV ANG WIDE RAT
1 40.00 18 1 106.20 110.75 5 .50 .0098 2.0 .0398 .67 114.77 10 2.0 0.00
2 54.00 18 1 111.00 114.50 5 .50 .0098 2.0 .0398 .67 119.36 90 4.0 0.00
3 30.00 12 1 109.93 111.88 5 .50 .0098 2.0 .0398 .67
File Opened for Reading:pipedata2.bwp
BACKWATER COMPUTER PROGRAM FOR PIPES
Pipe data from file:pipedata2.bwp
Surcharge condition at intermediate junctions
Tailwater Elevation:106.2 feet
Discharge Range:7. to 12. Step of 0.5 [cfs]
Overflow Elevation:121.9 feet
Weir:NONE
Upstream Velocity:0.5 feet/sec
PIPE NO.
l: 40
LF - 18"CP
@ 11.38% OUTLET:
106.20
INLET: 110.75 INTYP: 5
JUNC NO.
1: OVERFLOW -EL: 114.77 BEND:
10
DEG
DIA/WIDTH:
2.0
Q-RATIO:
0.00
Q(CFS)
HW(FT)
HW ELEV.
* N-FAC
DC
DN
TW
DO
DE
HWO
HWI
*******************************************************************************
7.00
1.32
112.07
* 0.012
1.03
0.44
0.00
0.44
1.03
*****
1.32
7.50
1.38
112.13
* 0.012
1.07
0.45
0.00
0.45
1.07
*****
1.38
8.00
1.43
112.18
* 0.012
1.10
0.47
0.00
0.47
1.10
*****
1.43
8.50
1.49
112.24
* 0.012
1.13
0.48
0.00
0.48
1.13
*****
1.49
9.00
1.57
112.32
* 0.012
1.17
0.50
0.00
0.50
1.17
*****
1.57
9.50
1.64
112.39
* 0.012
1.20
0.51
0.00
0.51
1.20
*****
1.64
10.00
1.72
112.47
* 0.012
1.22
0.53
0.00
0.53
1.22
*****
1.72
10.50
1.80
112.55
* 0.012
1.25
0.54
0.00
0.54
1.25
*****
1.80
11.00
1.89
112.64
* 0.012
1.28
0.55
0.00
0.55
1.28
*****
1.89
11.50
1.98
112.73
* 0.012
1.30
0.57
0.00
0.57
1.30
*****
1.98
12.00
2.07
112.82
* 0.012
1.32
0.58
0.00
0.58
1.32
*****
2.07
PIPE NO,
2: 54
LF - 18"CP
@ 6.481 OUTLET:
111.00
INLET: 111.50 INTYP: 5
'
JUNC NO.
2: OVERFLOW -EL: 119.36 BEND: 90
DEG
DIA/WIDTH:
4.0
Q-RATIO:
0.00
Q(CFS)
HW(FT)
HW ELEV.
* N-FAC DC
DN
TW
DO
DE
HWO
HWI
*******************************************************************************
'
7.00
1.59
116.09
* 0.012 1.03
0.51
1.07
1.07
1.03
*****
1.59
7.50
1.68
116.18
* 0.012 1.07
0.53
1.13
1.13
1.07
*****
1.68
8.00
1.77
116.27
* 0.012 1.10
0.54
1.18
1.18
1.10
*****
1.77
8.50
1.87
116.37
* 0.012
1.13
0.56
1.24
1.24
1.13 *****
1.87
9.00
1.99
116.49
* 0.012
1.17
0.58
1.32
1.32
1.17 *****
1.99
9.50
2.11
116.61
* 0.012
1.20
0.60
1.39
1.39
1.20 *****
2.11
10.00
2.23
116.73
* 0.012
1.22
0.61
1.47
1.47
1.22 *****
2.23
10.50
2.36
116.86
* 0.012
1.25
0.63
1.55
1.55
1.25
*****
2.36
'
11.00
2.50
117.00
* 0.012
1.28
0.65
1.64
1.64
1.28
*****
2.50
11.50
2.64
117.14
* 0.012
1.30
0.66
1.73
1.73
1.30
*****
2.64
'
12.00
2.71
117.21
* 0.012
1.32
0.68
1.82
1.82
1.32
*****
2.79
PIPE NO.
3: 30
LF - 12"CP
@ 6.50%
OUTLET:
109.93
INLET:
111.88
INTYP: 5
Q(CFS)
HW(FT)
HW ELEV.
* N-FAC
DC
DN
TW
DO
DE
HWO
HWI
*******************************************************************************
7.00
7.05
118.93
* 0.012
0.98
0.63
6.16
6.16
5.20
7.05
3.80
7.50
7.55
119.43
* 0.012
0.99
0.66
6.25
6.25
5.43
7.55
4.26
8.00
8.09
119.97
* 0.012
0.99
0.69
6.34
6.34
5.68
8.09
4.76
8.50
8.67
120.55
* 0.012
0.99
0.72
6.44
6.44
5.94
8.67
5.30
9.00
9.30
121.18
* 0.012
1.00
0.76
6.56
6.56
6.24
9.30
5.86
'
9.50
9.95
121.83
* 0.012
1.00
0.80
6.68
6.68
6.54
9.95
6.46
****************
OVERFLOW ENCOUNTERED
AT
10.00
CFS DISCHARGE
*****************
10.00
10.64
122.52
* 0.012
1.00
0.84
6.80
6.80
6.86
10.61
7.01
'
10.50
11.37
123.25
* 0.012
1.00
0.91
6.93
6.93
7.20
11.37
7.75
11.00
12.13
124.01
* 0.012
1.00
1.00
7.07
7.07
7.56
12.13
8.44
11.50
12.92
124.80
* 0.012
1.00
1.00
7.21
7.21
7.93
12.92
9.17
12.00 13.75 125.63 * 0.012 1.00 1.00 7.36 7.36 8.31 13.75 9.92
Exit KCBW Program
I
KING COUNTY DEPARTMENT OF NATURAL RESOURCES
Water and Land Resources Division
' BACKWATER ANALYSIS PROGRAM
Version 5.30h
t
1z"P,ec,
' Renton Ave S / S 3rd St Storm System Repair Project
D.Carey 8118/06
KING COUNTY DEPARTMENT OF NATURAL RESOURCES
Water and Land Resources Division
BACKWATER ANALYSIS PROGRAM
Version 5.30h
File Opened for Reading:pipedatal.bwp
REVIEW OF THE PIPE -DATA
PI OUTLET INLET IN OVERFLO BND STRU Q
# LENGTH DI TY ELEV ELEV TY KE K M C Y ELEV ANG WIDE RAT
1 40.00 12 1 106.20 110.75 5 .50 .0098 2.0 .0398 .67 114.77 10 2.0 0.00
2 54.00 12 1 111.00 114.50 5 .50 .0098 2.0 .0398 .67 119.36 90 4.0 0.00
3 30.00 12 1 109.93 111.88 5 .50 .0098 2.0 .0398 .67
File Opened for Reading:pipedatal.bwp
BACKWATER COMPUTER PROGRAM FOR PIPES
Pipe data from file:pipedatal.bwp
Surcharge condition at intermediate junctions
Tailwater Elevation:106.2 feet
Discharge Range:7. to 12. Step of 0.5 [cfs]
Overflow Elevation:121.9 feet
Weir:NONE
Upstream Velocity:0.5 feet/sec
PIPE NO.
1: 40
LF - 12"CP
@ 11.38% OUTLET:
106.20
INLET: 110.75 INTYP: 5
JUNC NO.
1: OVERFLOW
-EL: 114.77
BEND:
10
DEG
DIA/WIDTH:
2.0
Q-RATIO:
0.00
Q(CFS)
HW(FT)
HW ELEV.
* N-FAC
DC
DN
TW
DO
DE
HWO
HWI
*******************************************************************************
7.00
2.60
113.35
* 0.012
0.98
0.53
0.00
0.53
0.98
*****
2.60
7.50
2.90
113.65
* 0.012
0.99
0.55
0.00
0.55
0.99
*****
2.90
8.00
3.21
113.96
* 0.012
0.99
0.57
0.00
0.57
0.99
*****
3.21
8.50
3.54
114.29
* 0.012
0.99
0.59
0.00
0.59
0.99
*****
3.54
9.00
3.90
114.65
* 0.012
1.00
0.62
0.00
0.62
1.00
*****
3.90
****************
OVERFLOW ENCOUNTERED
AT
9.50
CFS DISCHARGE
*****************
********
OVERFLOW
CONDITIONS
CALCULATED
ASSUMING
SURCHARGE CONDITIONS
*********
9.50
4.28
115.03
* 0.012
1.00
0.64
0.00
0.64
1.00
*****
4.28
10.00
4.67
115.42
* 0.012
1.00
0.66
0.00
0.66
1.00
*****
4.67
10.50
5.09
115.84
* 0.012
1.00
0.69
0.00
0.69
1.00
*****
5.09
11.00
5.52
116.27
* 0.012
1.00
0.71
0.00
0.71
1.00
*****
5.52
11.50
5.98
116.73
* 0.012
1.00
0.74
0.00
0.74
1.00
*****
5.98
12.00
6.46
117.21
* 0.012
1.00
0.76
0.00
0.76
1.00
*****
6.46
PIPE NO.
2: 54
LF - 12"CP
@ 6.48% OUTLET:
111.00
INLET: 114.50 INTYP: 5
tJUNC
NO.
2: OVERFLOW
-EL: 119.36
BEND:
90
DEG
DIA/WIDTH:
4.0
Q-RATIO:
0.00
Q(CFS)
HW(FT)
HW ELEV. *
N-FAC
DC
DN
TW
DO
DE
HWO
HWI
*******************************************************************************
7.00
3.80
118.30 *
0.012
0.98
0.63
2.35
2.35
0.98
*****
3.80
'
7.50
4.27
118.77 *
0.012
0.99
0.66
2.65
2.65
0.99
*****
4.27
8.00
4.77
119.27 *
0.012
0.99
0.69
2.96
2.96
1.79
4.21
4.77
********
OVERFLOW
OVERFLOW ENCOUNTERED
CONDITIONS CALCULATED
AT
ASSUMING
8.50
CFS DISCHARGE
SURCHARGE
CONDITIONS
*****************
*********
8.50
5.30
119.80 *
0.012
0.99
0.72
3.29
3.29
2.41
5.15
5.30
9.00
6.15
120.65 *
0.012
1.00
0.76
3.65
3.65
3.09
6.15
5.86
9.50
7.21
121.71 *
0.012
1.00
0.80
4.03
4.03
3.80
7.21
6.46
10.00
8.33
122.83 *
0.012
1.00
0.84
4.42
4.42
4.55
8.33
7.09
10.50
9.50
124.00 *
0.012
1.00
0.91
4.84
4.84
5.33
9.50
7.75
'
11.00
11.50
10.73
12.02
125.23 *
126.52 *
0.012
0.012
1.00
1.00
1.00
1.00
5.27
5.73
5.27
5.73
6.16
7.02
10.73
12.02
8.44
9.17
12.00
13.37
127.87 *
0.012
1.00
1.00
6.21
6.21
7.93
13.37
9.93
PIPE NO.
3: 30
LF - 12"CP
@ 6.50%
OUTLET:
109.93
INLET:
111.88 INTYP: 5
Q(CFS)
HW(FT)
HW ELEV. *
N-FAC
DC
DN
TW
DO
DE
HWO
HWI
*******************************************************************************
7.00
9.26
121.14 *
0.012
0.98
0.63
8.37
8.37
7.41
9.26
3.80
****************
OVERFLOW ENCOUNTERED
AT
7.50
CFS DISCHARGE
*****************
7.50
10.14
122.02 *
0.012
0.99
0.66
8.84
8.84
8.02
10.14
4.26
'
8.00
11.09
122.97 *
0.012
0.99
0.69
9.34
9.34
8.68
11.09
4.76
8.50
12.10
123.98 *
0.012
0.99
0.72
9.87
9.87
9.37
12.10
5.30
9.01
13.46
125.34 *
0.012
1.00
0.76
10.72
10.72
10.40
13.46
5.86
'
9.50
15.05
126.93 *
0.012
1.00
0.80
11.78
11.78
11.65
15.05
6.46
10.00
16.74
128.62 *
0.012
1.00
0.84
12.90
12.90
12.96
16.74
7.09
10.50
18.51
130.39 *
0.012
1.00
0.91
14.07
14.07
14.34
18.51
7.75
'
11.00
11.50
20.36
22.30
132.24 *
134.18 *
0.012
0.012
1.00
1.00
1.00
1.00
15.30
16.59
15.30
16.59
15.79
17.31
20.36
22.30
8.44
9.17
12.00
24.33
136.21 *
0.012
1.00
1.00
17.94
17.94
18.89
24.33
9.92
Exit KCBW
Program
KING COUNTY
DEPARTMENT
OF
NATURAL
RESOURCES
Water
and Land
Resources
Division
BACKWATER
ANALYSIS
PROGRAM
'
Version
5.30h
Project: Renton Ave S Storm System Repair D. Carey
Final Design Revised: 8/11/06
PIPE FLOW CAPACITY BY MANNING EQUATION
For New 12" CPEP at Approx. 6.5% and 11.4%
Q = ( 1.49/n ) x A x R112/3 x S^1/2
For pipes flowing full, not under pressure conditions
Target Q =
10.40
For = 0.011
Q(cfs)
Pipe
Area Hyd. Rad.
Slope
Dia.(in)
( sq.ft.) (full, ft)
6.0% 6.5%
10.0%
11.0%
11.5% 12.0%
12
0.785 0.250
10.34 10.76
13.34
14.00
14.31 14.62
18
1.767 0.375
30.48 31.72
39.35
41.27
42.20 43.11
File: Runoff-TC4-CN-KCM.XLS - Tab: Pipe -Manning Q Page 1
/ErXCB
/
a '
/' TYPE 1 L
EX SDMH TYPE II �/ E EX CB
RIM EL=110.67 / TYPE I
NE 20' IE= 87.0 / = 114.77
SW 21' IE= 87.0 / E= 111.57
E 6' IE= 106.24 /
„—/ EX 6,-sn NEW 1B-SD
m
SSMH / \
/ Q E CURB,
STOP
G SIDEWALK SIGN CA
/
------------------ / �-
/ 1f
s
CAUTION
PROTECT SSMH D:
SS MH-48
RIM EL=118.84
EST IE= 110.9
112, \\\\� CALL 18 800-42 OURS 4E5555 FORE YOU DIG
EXISTING UTILITY LOCATIONS ARE APPROXIMATE, N0F ALL UTILTIES MAY BE SHOWN.
CONTRACTOR IS RESPONSIBLE FOR LOCATING ALL UTILITIES.
GENERAL NOTES:
\
EX 8" DI WATER
AMAIN STORM ONES MEASURED FROM CENTER OF STRUCTURES.
SERVICE TO HYDRANT
��
B. CONTRACTOR SHALL INSTALL EROSION CONTROL, MCLUDING
? DISCHARGES
FILTER FABRIC PROTECTION FOR DOWNSTREAM CAICHBASINS
Y",-'�
SOMEWHERE
IN THE AREA
ON SLOPE
TRENCH PATCH SHALL BE PER CITY DETAIL HR-23 TYPICAL
116
PATCH FOR FLEXIBLE PAVEMENT PERPENDICULAR m ROAD CL
/
/
D. CONCRETE CURB, GUTTER, SIDEWALK SHALL BE PER CITY DETAILS,
AND SHALL MATCH EXISTING.
/ '
llg
PLUG IN SDMH
EX SDMH TYPE II
RIM EL=119.36
S 12' IE=109.9,3
NORTH
ABANDDNED
l�o
_ _
-- 6- SIDE SEWER
DRAWING NOTES:
SCALE: 1 "= 1 0' (DRESTORE CURB, GUTTER, SIDEWALK AS NEEDED, MATCH EXISTING.
Q2 PLUG EX SO IN CB
RI rHTYPE .90 3 CORE DRILL CB FOR NEW SO PIPE.
RIM 11- GN,S�Dll
111.88 CI POTHOLE LOCATION.
L1J
`0
Li
EXISTING STORM SYSTEM REFERENCE PLANS:
R-1939 RENTON AVE S STREET IMPROVEMENT, APRIL 1983
I
R-2239 WSDOR SR-405 TUKWILA TO SUNSET BLVD, AUG. 1990
SCALE HORIZ:
1"= 19
:PROFILE ALONG NEV1f PIPE LINE
............................................................................................................................
TYPICAL TRENCH BEDDING AND BACKFILL wt)
VERT:
1"= 5'
'POTHOLE GAS LOC
'
:..........
TO 1 FT BELOW NEW SO
: CONTACT..P9E, BEFORE....:.......................................:
� � ...........
.. TRENCH EXCAVATION ............. ........ .
.................... .................... ....................
.................... .................... ....................
....................
.................... .................... .................... .........:...................
POTHOLING
P G E
a �
PAY LIhIIT 5' IJ' MAXIMUM
- E DET FOR PAVEMENT PATCH
SE AIL AVEM A:TC
:8" GAS ®
EX: SDMD
UNK EL_
RIM EL'-.7 L9 36
EX SDMH
'
NE S 12" IE=1:09.93
i
....................................................................................................................................................................................:.........................................................:...................�..................:...........
i RIM EL, 110.67 i
i
i i
i
• .
W i18' IE=114.50 ..:...._..... :. ............. ............. .............
12
.... ..... ...Q.:. ° ...... ..... ............. ............. .............
d MATERIAL
i i i
i NE 20" IE=i 67.0 i
SW 21' IE=: 87.D
i
CB-1, TYPE 1L i
6•'SS: APPROX LOG
NF.IR
Co M ABANDONED
Do�Eo
- ' MEETS $PEGS, OR IMPORT PER
aE NATIVE F
E 6' IE=:06.24 i
.FRAME AND GRATE
,
SE 9�0 BAN 6R VEL .
SECTION 319 (BANK RUN A )
i REMOVE N 6'
RIM EL-11i.n
i E 18' IE=111.00
SSMH-
' •:
..............................
i NEW E 18'?IE=106.2
W 18' IE-110.75.
RIM rL=118.84 i .... .....
.. ............. ...................... ............. ...........
... .............
...... ...... .... ........ ............. ............. ............. ..........
i
REMOVE EX CB
AND 6- PIPE
a
PIPE ZONE MATERIAL:
......................................:.}.�._....:............................................................................?...................?...................
5
.....................................................................
cns E
_..1.15...................................
PER WSDOT 2006ISECTION9-03.12(3)..........................'.
lz' MIN•': GRAVEL BACKFILL FOR PIPE ZONE BEDDING
:2
W UTILITY PIPE
NEW UTY
;ca�l0
--
...:......
.10 ....
E ST
ESSl'
^CAs
8'MIN
EXCAVATION OF UNSUITABLE SOIL (IF NEEDED)
A APPRO � Y ENGINEER
DEPTH S VED B
...................:...................'i�rJ.—....,...................:..................:.......Q......:..................,...................,...................,...................,....................................
3
:54 LF 18'CPEP O 0.064$ FT FT
............. ....................1.......................................
� � � � � .
ACKFILL TH FOUN AT10N MATE RIAL M ET1NG
s D
9w13.& QUAfRRY 9PALLS
L — -+ �— —. 1 SECTION
REMOVE EX 6'SD
40 LF 18'CPEP O 0.1138 FT/FT
1.� ROVIDE UNIFORM SUPPORT UNDER BARREL.
.......................................1 ........................._.............................................................................................'......................................................
fl0
t
... ...
2.: HAND TAMP UNDER: H AUNCHES.
.........................................................................................................
3.; COMPACT PIPE ZONE MliTERIAL TO 90% MINIMUM DENSITY
I
BE ND TA ONLY.
EXCEPT pIRECTLY OVER PIPE; WHERE CQMPACTION WILL HA MP
MANNER 0
4. PIPE MUST BE ANCHORED IN SUCH A A�AN A5 T
............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
ENSURE FLOW LINE IS MAINTAINED.
CHECKED FOR COMPLIANCE
TO CITY- STANDARDS— RECOMMENDED _ _ _ — _ — _ ®m A, Noted
CITY OF 8/1e/2006
FOR APPROVAL• ° RENTON AVE S / S 3rd ST
Date _ cxF owc �� RENTON STORM SYSTEM OUTFALL RELOCATION
BY DATUM
Date � <_ ��.e, Planning/Building/Public Works - Dept
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