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HomeMy WebLinkAboutExh.29_Storm_Drainage_Report
Cedar River Apartments
City of Renton, WA
Technical Information Report
January 2019 | Preliminary Report
EXHIBIT 29
RECEIVED
07/19/2019 mherrera
PLANNING DIVISION
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Cedar River Apartments – SRM Development
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Table of Contents
1 Project Overview ........................................................................................................................................... 1
2. Conditions and Requirements Summary ................................................................................................... 6
Core Requirement No. 1: Discharge at the Natural Location ................................................................... 6
Core Requirement No. 2: Off-Site Analysis .............................................................................................. 6
Core Requirement No. 3: Flow Control .................................................................................................... 6
Core Requirement No. 4: Conveyance System ....................................................................................... 7
Core Requirement No. 5: Construction Stormwater Pollution Prevention ............................................... 7
Core Requirement No. 6: Maintenance and Operations .......................................................................... 7
Core Requirement No. 7: Financial Guarantees and Liability .................................................................. 7
Core Requirement No. 8: Water Quality .................................................................................................. 8
Special Requirements .............................................................................................................................. 8
Special Requirement No. 1: Other Adopted Area-Specific Requirements ........................................ 8
Special Requirement No. 2: Flood Hazard Area Delineation ............................................................ 9
Special Requirement No. 3: Flood Protection Area Delineation ........................................................ 9
Special Requirement No. 4: Source Control ...................................................................................... 9
Special Requirement No. 5: Oil Control ............................................................................................. 9
Special Requirement No. 6: Aquifer Protection Area ........................................................................ 9
Supplemental Requirements .................................................................................................................... 9
3. Off-Site Analysis ......................................................................................................................................... 10
Task 1: Study Area Definition and Maps ................................................................................................ 10
Task 2: Resource Review ...................................................................................................................... 10
Off-Site Analysis Reports ................................................................................................................. 10
Basin Plan ........................................................................................................................................ 11
Floodplain and Floodway Research ................................................................................................ 11
Wetlands Inventory .......................................................................................................................... 11
Soil Conditions ................................................................................................................................. 11
Section 303 (d) List of Polluted Waters ........................................................................................... 11
Task 3: Field Inspection ......................................................................................................................... 12
Task 4: Drainage System Description and Problem Descriptions ......................................................... 12
Task 5: Mitigation of Existing or Potential Problems .............................................................................. 12
4. Flow Control, LID, and Water Quality Facility Analysis and Design ..................................................... 12
Part 4.A: Existing Site Hydrology ........................................................................................................... 12
Part 4.B: Developed Site Hydrology ....................................................................................................... 13
Part 4.C: Performance Standards .......................................................................................................... 14
Part 4.D: Flow Control System ............................................................................................................... 14
Part 4.E: Water Quality System .............................................................................................................. 14
5. Conveyance System Analysis and Design............................................................................................... 15
6. Special Reports and Studies ..................................................................................................................... 16
7. Other Permits .............................................................................................................................................. 16
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8. Construction Stormwater Pollution Prevention Plan (CSWPPP) Analysis and Design...................... 17
Part A: Erosion and Sediment Control Plan Analysis and Design ........................................................ 17
Part B: Stormwater Pollution Prevention Plan (SWPPP) Design .......................................................... 18
9. Bond Quantities, Facility Summaries, and Declaration of Covenant ................................................... 18
10. Maintenance and Operations Manual ...................................................................................................... 18
List of Figures
Figure 1: TIR Worksheet ................................................................................................................................... 1.i
Figure 2: Project Site Location Map ..................................................................................................................... 2
Figure 3.1: Existing Drainage Basins and Sub-basins ......................................................................................... 3
Figure 3.2: Proposed Drainage Basins and Sub-basins ...................................................................................... 4
Figure 4: Soils ...................................................................................................................................................... 5
Figure 5: Confluence Map ................................................................................................................................... 6
Figure 6: Study Area Map .................................................................................................................................. 10
List of Tables
Table 4-1: Existing Basin Conditions .................................................................................................................. 13
Table 4-2: Water Quality Facility Overview ........................................................................................................ 15
Table 5-1: Proposed Conveyance Design ......................................................................................................... 16
Table 7-1: List of Permits ................................................................................................................................... 16
Appendices
Appendix A – Operations and Maintenance Manual
Appendix B – Site Improvement Plan
Appendix C – TESC, Water Quality, and Conveyance Calculations and Design Analysis
Appendix D – Bond Quantities, Facility Summaries, and Declaration of Covenant
Appendix E – Special Reports and Studies
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1. Project Overview
This report documents the drainage analysis for the Cedar River Apartment project.
The project is located at 1915 Southeast Maple Valley Highway, Renton, Washington. It is bordered by Maple
Valley Highway (SR-169) to the northeast, Cedar River Park Drive to the north, the Renton Community Center
to the northwest, and the Cedar River to the south (see Figure 1). The proposed project site consists of a
12.54-acre property and approximately 0.19 acres of frontage improvements in existing City Right-of-Way. An
additional 0.06 acres of the property along Cedar River Park Drive and Maple Valley Highway will be dedicated
to the City to allow for the required frontage improvements. The soil characteristics of the site consist of mostly
Riverwash (Rh) and Pilchuck loamy fine sand (Pc) near the north side (see Figure 4). The site is in a
Commercial Office Residential Zone (CORZ).
The site is currently a compacted gravel lot with minimal vegetation. The majority of the site is relatively flat
and gradually slopes from the northeast to the south, with an elevation change of approximately 20 feet across
the site. The southeast corner of the site has steep slopes exceeding 15 percent.
There are existing City and privately owned monitoring wells on-site. The City monitoring wells on-site will be
preserved or replaced and all other on-site wells will be abandoned.
There is existing stormwater conveyance infrastructure in the Maple Valley Highway and Cedar River Park
Drive right-of-way, but there is no existing on-site stormwater conveyance system.
The project proposes to construct two mixed-use buildings consisting of multi-family and commercial space
with associated parking, pedestrian hardscape, and amenity areas. A commercial development will occur on
the northern portion of the site at a later date. The scope of this project is to provide a stabilized footprint for
future development in this portion of the site.
The proposed development will require a new stormwater conveyance system with two new outfalls near the
Cedar River. New pollution-generating surfaces will be treated using Best Management Practices (BMPs) that
meet enhanced basic water quality standards.
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CITY OF RENTON SURFACE WATER DESIGN MANUAL
2017 City of Renton Surface Water Design Manual 12/12/2016 8-A-1
REFERENCE 8-A
TECHNICAL INFORMATION REPORT (TIR)
WORKSHEET
Part 1 PROJECT OWNER AND
PROJECT ENGINEER Part 2 PROJECT LOCATION AND
DESCRIPTION
Project Owner _____________________________
Phone ___________________________________
Address __________________________________
_________________________________________
Project Engineer ___________________________
Company _________________________________
Phone ___________________________________
Project Name __________________________
CED Permit # ________________________
Location Township ________________
Range __________________
Section _________________
Site Address __________________________
_____________________________________
Part 3 TYPE OF PERMIT APPLICATION Part 4 OTHER REVIEWS AND PERMITS
Land Use (e.g., Subdivision / Short Subd.)
Building (e.g., M/F / Commercial / SFR)
Grading
Right-of-Way Use
Other _______________________
DFW HPA
COE 404
DOE Dam Safety
FEMA Floodplain
COE Wetlands
Other ________
Shoreline
Management
Structural
Rockery/Vault/_____
ESA Section 7
Part 5 PLAN AND REPORT INFORMATION
Technical Information Report Site Improvement Plan (Engr. Plans)
Type of Drainage Review
(check one):
Date (include revision
dates):
Date of Final:
Full
Targeted
Simplified
Large Project
Directed
__________________
__________________
__________________
Plan Type (check
one):
Date (include revision
dates):
Date of Final:
Full
Modified
Simplified
__________________
__________________
__________________
1.i
x
17
05
SE 23
Civil Construction
x
x
x
x
x
x
Renton, WA 98057
1915 Maple Valley Highway
Cedar River Apartments
425.803.3355 ext.253
Kirkland, WA 98033
720 6th Street South, Suite 200
206.622.5822
KPFF Consulting Engineers
David Schwartz
SRM Development
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
REFERENCE 8: PLAN REVIEW FORMS AND WORKSHEET
TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
12/12/2016 2017 City of Renton Surface Water Design Manual 8-A-2
Part 6 SWDM ADJUSTMENT APPROVALS
Type (circle one): Standard / Blanket
Description: (include conditions in TIR Section 2)
____________________________________________________________________________________
____________________________________________________________________________________
____________________________________________________________________________________
Approved Adjustment No. ______________________ Date of Approval: _______________________
Part 7 MONITORING REQUIREMENTS
Monitoring Required: Yes / No
Start Date: _______________________
Completion Date: _______________________
Describe: _________________________________
_________________________________________
_________________________________________
Re: SWDM Adjustment No. ________________
Part 8 SITE COMMUNITY AND DRAINAGE BASIN
Community Plan: ____________________________________________________________________
Special District Overlays: ______________________________________________________________
Drainage Basin: _____________________________________________________________________
Stormwater Requirements: _____________________________________________________________
Part 9 ONSITE AND ADJACENT SENSITIVE AREAS
River/Stream ________________________
Lake ______________________________
Wetlands ____________________________
Closed Depression ____________________
Floodplain ___________________________
Other _______________________________
_______________________________
Steep Slope __________________________
Erosion Hazard _______________________
Landslide Hazard ______________________
Coal Mine Hazard ______________________
Seismic Hazard _______________________
Habitat Protection ______________________
_____________________________________
1.ii
Cedar River Basin
Critical Aquifer Recharge Areax
The Renton Chinook Conservation Strategy for the Water Resource Inventory Area (WRIA) 8 details
City of Renton's plans to mitigate runoff for salmon conservation. (Recommendations only)
The 2014 King County Regional Hazard Mitigation Plan provides planning area wide elements for hazard
requirements in Table 3 of Appendix B.
100-yearx
x Cedar River
Aquifer Protection Area
N/A
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REFERENCE 8-A: TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
2017 City of Renton Surface Water Design Manual 12/12/2016 Ref 8-A-3
Part 10 SOILS
Soil Type
______________________
______________________
______________________
______________________
Slopes
________________________
________________________
________________________
________________________
Erosion Potential
_________________________
_________________________
_________________________
_________________________
High Groundwater Table (within 5 feet)
Other ________________________________
Sole Source Aquifer
Seeps/Springs
Additional Sheets Attached
Part 11 DRAINAGE DESIGN LIMITATIONS
REFERENCE
Core 2 – Offsite Analysis_________________
Sensitive/Critical Areas__________________
SEPA________________________________
LID Infeasibility________________________
Other________________________________
_____________________________________
LIMITATION / SITE CONSTRAINT
_______________________________________
_______________________________________
_______________________________________
_______________________________________
_______________________________________
_______________________________________
Additional Sheets Attached
Part 12 TIR SUMMARY SHEET (provide one TIR Summary Sheet
per Threshold Discharge Area)
Threshold Discharge Area:
(name or description)
Core Requirements (all 8 apply):
Discharge at Natural Location Number of Natural Discharge Locations:
Offsite Analysis Level: 1 / 2 / 3 dated:__________________
Flow Control (include facility
summary sheet)
Standard: _______________________________
or Exemption Number: ____________
On-site BMPs: _______________________________
Conveyance System Spill containment located at: _____________________________
Erosion and Sediment Control /
Construction Stormwater Pollution
Prevention
CSWPP/CESCL/ESC Site Supervisor: _____________________
Contact Phone: _________________________
After Hours Phone: _________________________
1.iii
07/13/2017
2
1
(1) Steep Riverwash slopes up to 100% in SE bottom corner of property.
(2) Consult the Geotechnical Report for more detail.
~ 2%-25%
~ 2.5%-40%Uncategorized
K-factor = 0.2, T-factor =4 (USDA)
Direct discharge exemption
No open facilities, BMPs that rely on infiltration, or open
conveyance systems.
Critical Aquifer
Recharge Areax
x
Pilchuck loamy fine sand
Riverwash
See above
TBD by contractor
1
#1
No open facilities, BMPs that rely on infiltration, or open
conveyance systems in FHA.
Aquifer Protection Area-no infiltration
FEMA Flood Hazard Areax
x
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
REFERENCE 8: PLAN REVIEW FORMS AND WORKSHEET
TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
12/12/2016 2017 City of Renton Surface Water Design Manual 8-A-4
Part 12 TIR SUMMARY SHEET (provide one TIR Summary Sheet
per Threshold Discharge Area)
Maintenance and Operation Responsibility (circle one): Private / Public
If Private, Maintenance Log Required: Yes / No
Financial Guarantees and Liability Provided: Yes / No
Water Quality (include facility
summary sheet)
Type (circle one): Basic / Sens. Lake / Enhanced Basic / Bog
or Exemption No. _______________________
Special Requirements (as applicable):
Area Specific Drainage
Requirements
Type: SDO / MDP / BP / Shared Fac. / None
Name: ________________________
Floodplain/Floodway Delineation Type (circle one): Major / Minor / Exemption / None
100-year Base Flood Elevation (or range): _______________
Datum:
Flood Protection Facilities Describe:
Source Control
(commercial / industrial land use)
Describe land use:
Describe any structural controls:
Oil Control High-Use Site: Yes / No
Treatment BMP: _________________________________
Maintenance Agreement: Yes / No
with whom? _____________________________________
Other Drainage Structures
Describe:
1.iv
NAVD 88
42.60-44.36 feet
/ Other
Hazard Mitigation Plan
None required
Mixed use residential/commerical
None
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
REFERENCE 8-A: TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
2017 City of Renton Surface Water Design Manual 12/12/2016 Ref 8-A-5
Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS
MINIMUM ESC REQUIREMENTS
DURING CONSTRUCTION
Clearing Limits
Cover Measures
Perimeter Protection
Traffic Area Stabilization
Sediment Retention
Surface Water Collection
Dewatering Control
Dust Control
Flow Control
Control Pollutants
Protect Existing and Proposed
BMPs/Facilities
Maintain Protective BMPs / Manage
Project
MINIMUM ESC REQUIREMENTS
AFTER CONSTRUCTION
Stabilize exposed surfaces
Remove and restore Temporary ESC Facilities
Clean and remove all silt and debris, ensure
operation of Permanent BMPs/Facilities, restore
operation of BMPs/Facilities as necessary
Flag limits of sensitive areas and open space
preservation areas
Other _______________________
Part 14 STORMWATER FACILITY DESCRIPTIONS (Note: Include Facility Summary and Sketch)
Flow Control Type/Description Water Quality Type/Description
Detention
Infiltration
Regional Facility
Shared Facility
On-site BMPs
Other
________________
________________
________________
________________
________________
________________
Vegetated Flowpath
Wetpool
Filtration
Oil Control
Spill Control
On-site BMPs
Other
________________
________________
________________
________________
________________
________________
________________
Part 15 EASEMENTS/TRACTS Part 16 STRUCTURAL ANALYSIS
Drainage Easement
Covenant
Native Growth Protection Covenant
Tract
Other ____________________________
Cast in Place Vault
Retaining Wall
Rockery > 4′ High
Structural on Steep Slope
Other _______________________________
1.v
x
x
x
x
x
None required
None required
None required
None required
None required
River Protection Easementx
x
Proprietary Systemx
x
x
x
x
x
x
x
x
x
x
x
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
REFERENCE 8: PLAN REVIEW FORMS AND WORKSHEET
TECHNICAL INFORMATION REPORT (TIR) WORKSHEET
12/12/2016 2017 City of Renton Surface Water Design Manual 8-A-6
Part 17 SIGNATURE OF PROFESSIONAL ENGINEER
I, or a civil engineer under my supervision, have visited the site. Actual site conditions as observed were
incorporated into this worksheet and the attached Technical Information Report. To the best of my
knowledge the information provided here is accurate.
____________________________________________________________________________________
Signed/Date
1.vi
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Figure 2: Project Site Location Map
N
Property
Boundary
Project Site Limits
Cedar River
Cedar River
Park Drive
Maple
Valley
Highway
(SR-169)
Steep
Slopes
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Cedar River Apartments – SRM Development
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Figure 3.1: Existing Drainage Basins and Sub-Basins
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KPFF Consulting Engineers
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Figure 3.2: Proposed Drainage Basins and Sub-Basins
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Cedar River Apartments – SRM Development
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Figure 4: Soils Riverwash (Rh) Water (W) Pilchuck loamy fine sand (Pc) Project Site Limits Off-site Drainage Basin (TYP) DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
KPFF Consulting Engineers
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2. Conditions and Requirements Summary
The proposed site improvements require a “Full Drainage Review” per the 2017 City of Renton Surface Water
Design Manual (CORSWDM), Section 1.1.2.4. The following is a summary of how the project will comply with
the nine core requirements and six special requirements:
CORE REQUIREMENT NO. 1: DISCHARGE AT THE NATURAL LO CATION
Discharge from the project site will continue to discharge at the natural discharge locations to the Cedar River.
The project meets the discharge requirements in Section 1.2.1 of the 2017 CORSWDM because all
stormwater runoff and surface water from the project site will be discharged directly to a major receiving water.
Stormwater runoff from the frontage improvements will not be redirected as a result of this project. The on-site
drainage facilities are not anticipated to create a significant adverse impact to downstream properties or
drainage systems.
CORE REQUIREMENT NO. 2: OFF-SITE ANALYSIS
A Level 1 downstream analysis is included in Section 3 of this report, as required by Section 1.2.2 of the 2017
CORSWDM.
CORE REQUIREMENT NO. 3: FLOW CONTROL
Not applicable. The project qualifies for the direct discharge exemption because it drains to one of the major
receiving waters listed in Table 1.2.3.B and meets all five criteria for direct discharge in the 2017 CORSWDM.
See Figure 5 for the location of the project site on the Cedar River downstream of Taylor Creek confluence.
Figure 5: Confluence Map
Project Site
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The following bullet points demonstrate how stormwater runoff from the project site meets all five criteria for
the direct discharge exemption referenced above:
· The project site discharge points are within the 100-year floodplain of the Cedar River.
· The conveyance system on the project site extends to the ordinary high water mark of the Cedar River.
· The conveyance system has adequate capacity to convey the 25-year peak flow for the entire
contributing drainage area under full build-out conditions under current zoning, including the future
commercial building on the northwest corner of the property.
· The conveyance system will discharge to stabilized areas consisting of rock lining per Section 4.2.2 of
the CORSWDM.
· The proposed direct discharge does not divert flows from or increase flows to an existing wetland or
stream.
CORE REQUIREMENT NO. 4: CONVEYANCE SYSTEM
There is no existing stormwater conveyance system.
The site is located in Zone 1 of the Aquifer Protection Area (APA) and will utilize a piped conveyance system
that drains to the site’s natural discharge location to the Cedar River per Section 1.2.4.3.B of the CORSWDM.
See Section 5 of this report for analysis and design of the proposed conveyance system within the project site.
CORE REQUIREMENT NO. 5: CONSTRUCTION STORMWATER POL LUTION
PREVENTION
Temporary Erosion and Sediment Control (TESC) BMPs will be implemented during construction to prevent, to
the maximum extent practicable, the transport of sediment from the project site. TESC BMPs are anticipated
to include silt fences, conveyance swales, check dams, a sediment pond with a liner, catch basin inserts,
mulching of exposed areas, dust control, and other measures as necessary.
See Section 8 of this report for the Construction Stormwater Pollution Prevention Plan analysis and design.
CORE REQUIREMENT NO. 6: MAINTENANCE AND OPERATIONS
The owner is responsible for the maintenance and operations of the proposed drainage facilities. A
maintenance and operations manual is provided in Appendix A of this report.
CORE REQUIREMENT NO. 7: FINANCIAL GUARANTEES AND LI ABILITY
The project will post a construction bond, assignment of funds, or a certified check before a building permit is
issued in accordance with the COR Municipal Code 4-6-030. The applicant will also maintain liability insurance
throughout the duration of construction. A maintenance bond will also be submitted to the City of Renton
before receiving acceptance of any newly constructed on-site private storm drain improvements.
See Section 9 of this report for the City of Renton Bond Quantity Worksheet for this project.
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CORE REQUIREMENT NO. 8: WATER QUALITY
The project site falls within the Enhanced Basic Water Quality (EWQ) treatment area per the CORSWDM,
Section 6.1.2. The project will treat runoff from all target pollution-generating impervious surfaces (PGIS)
using the three Filterra system units. Contech’s Filterra system is a proprietary facility satisfying Option 5 of the
Enhanced Basic treatment approach. The system has received the General Use Level Designation (GULD) for
enhanced treatment through the Technology Assessment Protocol – Ecology (TAPE) process. A copy of the
certification is included in Appendix C.
See Section 4 of this report for Water Quality Facility Analysis and Design including drainage areas to each
Filterra system unit.
CORE REQUIREMENT NO. 9: ON-SITE BMPS
The project site is site greater than 22,000 square feet and is subject to “large lot BMP requirements.” The
project qualifies for flow control facility exemption through the Direct Discharge Exemption in accordance with
Section 1.2.3.1 of the CORSWDM and is not required to achieve the Low-Impact Development (LID)
performance standards.
On-site BMPs that involve infiltration, open stormwater facilities, and connections to sub-surface drains are not
allowed in Zone 1 of the APA; therefore, infiltration testing to determine the feasibility of on-site infiltration
BMPs is not required per Section 1.2.9 of the CORSWDM. The following BMPs are infeasible for the project
site: full dispersion, full or limited infiltration, bioretention, permeable pavement requirements, and perforated
pipe connections.
The project is not eligible for the tree retention credit because there are no existing trees within 20 feet of new
or replaced ground level impervious surfaces. Similarly, the project is not eligible for the native growth retention
credit because there are no areas of native growth on slopes flatter than 15% within the project. Finally, the
reduced impervious surface is not feasible within the commercial office residential zone (CORZ).
Basic dispersion by sheet flow will be provided for hard surfaces within the 100-foot Cedar River buffer. Use of
splash blocks and rock pads to achieve a basic dispersion buffer are infeasible because the contributing area
from roofs and other hard surfaces exceed 700 square feet. Likewise, the maximum amount of contributing
area from impervious surfaces is exceeded at the piped conveyance system outfall locations.
Soil amendment will be applied to all new pervious surfaces in accordance with Appendix C.2.13 of the
CORSWDM.
SPECIAL REQUIREMENTS
In addition to the nine core requirements, the project must evaluate compliance with the six special
requirements:
Special Requirement No. 1: Other Adopted Area-Specific Requirements
The site is adjacent to the lower Cedar River and is part of the Tier 1 subareas for salmon conservation. The
Renton Chinook Conservation Strategy for the Water Resource Inventory Area (WRIA) 8 details suggested
guidelines to mitigate runoff through mechanisms such as habitat improvements, regulations, incentives, and
BMPs as designated by the state under WAC 173-500-040.
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Salmon conservation plans are not required in the City of Renton. However, implementing stormwater quality
treatment facilities will reduce fish exposure to pollution and harmful water quality conditions.
The COR’s Hazard Mitigation Plan provides planning area-wide elements for hazard requirements. The project
will provide compensatory floodplain storage for fill within the floodplain. Other general requirements are listed
in Table 3 of the “Current Progress on Action Plan Initiatives” on the King County Hazard Mitigation Plan.
Special Requirement No. 2: Flood Hazard Area Delineation
The final 100-year floodplain and applicable floodway boundaries will be delineated on the final site
improvement plans. Upon completion of their study, Golder Associates Inc. will indicate in their report the
boundaries of the severe and moderate channel migration hazard area in accordance with RMC 4-3-050 and
associated public rules.
Special Requirement No. 3: Flood Protection Area Delineation
The proposed project will not rely on existing or proposed flood protection facilities for protection against
hazards posed by erosion or inundation. Therefore, there are no flood protection area delineation
requirements.
Special Requirement No. 4: Source Control
Water quality source controls applicable to this project will be applied in accordance with the King County
Stormwater Pollution Prevention Manual and Renton Municipal Code, Title IV.
See Section 8 of this report for the Construction Stormwater Pollution Prevention Plan Analysis and Design.
Special Requirement No. 5: Oil Control
This requirement is not applicable. Based on the Traffic Impact Analysis prepared by William Popp Associates,
dated September 21, 2017, the proposed development is not classified as a high-use site because the
commercial-related expected Average Daily Traffic (ADT) will be less than 100 vehicles per 1,000 square feet
of gross building area for the commercial space.
Special Requirement No. 6: Aquifer Protection Area
The site is in Zone 1 of the City’s APA, as identified in the RMC 4-3-050, and is prohibited from using open
stormwater facilities, stormwater BMPs that rely on infiltration, and open conveyance systems.
SUPPLEMENTAL REQUIREMENTS
In addition to the nine core and five special requirements, this report is required to document the following to
the extent known: the applicable critical area requirements and development requirements (conditional use
permits, rezones, variances and adjustments, State Environmental Policy Act (SEPA) mitigations, etc.). See
Appendix E for attachments.
No additional requirements are known at this time. Documentation will be added to Appendix E in the event
unanticipated requirements arise.
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3. Off-Site Analysis
TASK 1: STUDY AREA DEFINITION AND MAPS
Flow from the site discharges to Cedar River and flows northwest to Lake Washington. The project site is
12.73 acres and receives another 0.19 acres of off-site drainage. Off-site drainage areas are shown in Figures
3.2 and 6.
Figure 6: Study Area Map
TASK 2: RESOURCE REVIEW
All resources listed from the CORSWDM were reviewed for potential problems in the study area. These
include information from off-site analysis reports, basin plans, FEMA maps, wetland inventory maps, soil
survey data, sensitive area map folios, City of Renton erosion and landslide maps, and Washington State
water quality atlas maps.
Off-Site Analysis Reports
The Cedar River Current and Future Conditions Report from 1993 offers an off-site analysis report regarding
flooding, erosion and deposition, aquatic habitat, and water quality conditions. The Lower Cedar River Basin
was ranked number one due to the relative importance of its natural resources and the need to protect the
area from further water quality degradation. According to the report’s maps compiled from 1991 Environmental
Protection Agency (EPA) data, the site is within the Lower Mainstem sub-basin, part of the City of Renton
Planning Area, in a moderate recharge area consisting of alluvium soils; is part of the MS1 catchment area,
which has one reported hazardous waste generator; and is near a Small Quantity Generator (SQG) that has
led to a nonpoint water quality problem, which includes erosion and flooding problems. Further flood mitigation
is of continual interest for future development to reduce channel erosion and pollution runoff. Increased land-
use development and pollution generating activities have decreased the historically high water quality in the
Cedar River Basin Planning Area (BPA) through increased volumes of stormwater runoff and stream flows.
King County’s initial documented surface water conditions are included in the 1987 Lower Cedar River Basin
Reconnaissance Report.
Project and
Study Area
Boundary
Site Discharge Points
Off-site
Drainage
Areas (TYP)
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Basin Plan
King County’s Cedar River Basin Plan and Nonpoint Pollution Action Plan prioritizes key recommendations
into a Core Plan that identifies ongoing programs to resolve hazardous flooding, protect and restore the most
valuable natural aquatic habitats, and maintain the Cedar River’s high water quality. The major problems in the
Cedar Basin are flooding hazards and declining salmon and steelhead runs. The primary goal is to maintain
the generally high surface water and groundwater quality in the basin.
Floodplain and Floodway Research
The FEMA Flood Map Service Center shows the most recent flood insurance maps as of September 15, 2017,
for the 100-year floodplain on the southern portion of the site. More than 8 feet will be provided between the
proposed lowest finished floor elevation and the Base Flood Elevation (BFE). The existing 100-year floodplain
boundary is indicated on the site improvement plans found in Appendix B of this report.
Wetlands Inventory
The U.S. Fish and Wildlife National Wetlands Inventory map website indicates that the Cedar River is
classified as a R3UBH wetland (Riverine, Upper Perennial, Unconsolidated Bottom, and Permanently
Flooded) habitat. The maps indicates a 0.9-acre area of wetland bordering the northern portion of the property
classified as a R4SBC (Riverine, Intermittent, Streambed, Seasonally Flooded) habitat. This area is upstream
of the project site and will not be impacted by the project.
Soil Conditions
The USDA Web Soil Survey has provided a basic understanding of existing soil conditions. The majority of the
site consists of Riverwash soil, as shown in Figure 4.
The site has protected and sensitive slopes in the lower east corner that exceed at least 25% over 15 feet of
vertical rise per the RMC 4-3-050.
The King County Landslide Hazard Areas Map for Sensitive Areas Ordinance (SAO) Designations from
October 31, 2006, shows the approximate boundaries of landslide hazards. The map indicates that the site is
in a park category and does not appear to trigger landslide hazards. The City of Renton Sensitive Areas map
also does not indicate any landslide hazards on-site.
The King County GIS map indicates that the site lies within the 1990 SAO erosion hazard region. According to
the King County planning and critical area designations, the site may be subject to erosion hazards.
See Section 4.A of this report for existing topsoil conditions at the project site.
Section 303 (d) List of Polluted Waters
The Washington State Water Quality Atlas on the Department of Ecology’s website identifies Cedar River to
Lake Washington as a freshwater, core summer salmonid habitat that has been rated in three different water
categories for downstream locations of the project site. The City of Renton recognizes Categories 2, 4, and 5
as problems that require additional mitigation. Category 1 listings consist of copper, ammonia-N, arsenic,
selenium, and bacteria, which meet tested standards for clean waters. Mercury has been rated into Category 2
as a concern for the water body. Category 5 listings include pH, temperature, and dissolved oxygen,
classifying them as “polluted waters” that require water improvements. Downstream water quality problems
that require special attention within the area 1/4 mile to 15 percent of the total discharge area distance
determined by the State of Washington include dissolved oxygen, temperature, metals, and high pH. Listed
below are the requirements for the four water quality issues.
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· Dissolved Oxygen (DO) Problem (Type 2)
The three requirements are not applicable. The project’s downstream analysis did not indicate the
dissolved oxygen problem to be caused by excessive phosphorus and is not proposing a new wetpond
or wetvault.
· Temperature Problem (Type 3)
The two requirements are not applicable. The project does not propose a new wetpond and is prohibited
from using open drainage features.
· Metals Problem (Type 4)
A water quality facility option from the Enhanced Basic Water Quality Menu is required. The proposed
project includes right-of-way improvements and must avoid leachable heavy metals to the extent
practical (e.g., galvanized metals) that will be exposed to the weather (e.g., guard rails, street lights,
etc.).
· High pH Problem (Type 7)
All proposed concrete vault structure submerged surfaces for stormwater control purposes must be
coated or otherwise treated to prevent alteration of pH.
TASK 3: FIELD INSPECTION
The design engineer conducted a Level 1 investigation of the existing on-site and off-site drainage systems of
the project site and its vicinity on July 13, 2017. No existing or potential constrictions or downstream drainage
problems were noted.
TASK 4: DRAINAGE SYSTEM DESCRIPTION AND PROBLEM DES CRIPTIONS
The project site currently sheet flows to the Cedar River. There is no formal drainage system, and therefore,
there are no drainage system components or problems to describe.
TASK 5: MITIGATION OF EXISTING OR POTENTIAL PROBLEM S
No existing or potential problems were noted in the off-site review for existing erosion, flooding, or landslide.
4. Flow Control, LID, and Water Quality Facility Analysis and
Design
PART 4.A: EXISTING SITE HYDROLOGY
The project consists of one threshold discharge area because the existing conveyance systems combine
within 1/4 mile downstream. This threshold discharge area is divided into three drainage basins because each
basin has a distinct discharge location to the Cedar River.
Basin 1 consists of the area located behind the Maple Valley Highway curb shown in Figure 3.1. Stormwater
from Basin 1 is collected by existing catch basins in Maple Valley Highway and conveyed to an existing 24-
inch outfall to the Cedar River approximately 100 feet east of the project site. The existing land cover consists
of a concrete sidewalk.
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Basin 2 consists of the area located behind the Cedar River Park Drive curb shown in Figure 3.1. Stormwater
from Basin 2 eventually discharges to the Cedar River through an existing 12-inch outfall approximately 800
feet west of the project site. The existing land cover consists of a concrete sidewalk.
Basin 3 consists of the project site and off-site drainage areas along the north and eastern property lines.
Stormwater from Basin 3 sheet flows south and discharges to the Cedar River. There is no existing stormwater
collection or conveyance infrastructure on-site. The existing land cover within Cedar River Park Drive consists
of asphalt roadway, concrete curb, gutter and sidewalk, and minimal vegetation. The project site consists
primarily of gravel with minimal vegetation and a concrete retaining wall along the Cedar River. The project site
gradually slopes north to south.
Table 4-1: Existing Basin Conditions
Area (acres) Soil Type Land Cover
Basin 1 0.14 Till Sidewalk
Basin 2 0.05 Till Sidewalk
Basin 3: On-Site
and Off-Site 12.73 Till Asphalt road; gravel; concrete retaining wall;
vegetation; concrete curb, gutter, and sidewalk
The geotechnical report prepared by Terracon Consultants, Inc. on October 31, 2018, indicates loose to
medium dense alluvium and medium dense to very dense alluvium soil types on the project property. Alluvial
soils are classified as till soils with a hydrologic soil group C per Section 3.2.2 of the CORSWDM.
Refer to Figure 3.1 for a graphical representation of the existing basins and outfalls.
PART 4.B: DEVELOPED SITE HYDROLOGY
The developed site hydrology will maintain the three drainage basins described above. Refer to Figure 3.2 for
a graphical representation of the proposed drainage basins, sub-basins, and outfalls.
The addition of landscaping on both sides of the Maple Valley Highway sidewalk will expand the developed
Basin 1 drainage area. The replaced sidewalk and all landscaping within the Maple Valley Highway right-of-
way will drain to the existing catch basins in Maple Valley Highway and continue to be conveyed to the existing
outfall to the Cedar River.
The addition to landscaping on both sides of the Cedar River Park Drive, sidewalk will expand the developed
Basin 2 drainage area. The replaced sidewalk and all landscaping within the Cedar River Park Drive right-of-
way will drain to an existing catch basin in Cedar River Park Drive and continue to be conveyed to the existing
outfall to the Cedar River.
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Basin 3 will consist of the remainder of the project site and the off-site drainage basins shown in Figure 3.2.
The proposed land cover will consist of asphalt pavement, gravel, concrete curb and sidewalk, building roofs, a
permeable fire lane, pedestrian hardscape, paved amenity areas, retaining walls, and landscaping. Stormwater
will be collected through new catch basins and area drains and be conveyed through tightline storm drain
pipes and roof leaders. Basin 3 will discharge to the Cedar River at two new outfall locations identified in
Figure 3.2.
Basin 3 is divided into several sub-basins. The drainage areas for each water quality facility are broken up into
on-site and off-site sub-basins. Filterra WQ Unit No. 1 receives runoff from Sub-Basin 3.A and Sub-Basin 3F.1.
Filterra WQ Unit No. 2 receives runoff from Sub-Basin 3A.2 and Sub-Basin 3F.3. Filterra WQ Unit No. 3
receives runoff from Sub-Basin 3A.3.
Sub-Basin 3B is the future commercial development. This future development area is north of the inner drive
aisle and will be covered by gravel. It will be graded to sheet flow to a shallow swale that will convey
stormwater runoff to a catch basin and connect downstream of the water quality facility in the eastern
conveyance system.
Sub-Basins 3A.3, Sub-Basin 3B, Sub-Basin 3C, and off-site Sub-Basin 3F.3 are conveyed to a new outfall near
the Cedar River. Sub-Basin 3A.1, Sub-Basin 3A.2, Sub-Basin 3D, off-site Sub-Basin 3F.1, and off-site Sub-
Basin 3F.2 are collected by a separate on-site conveyance system. This system will outfall near the Cedar
River. Finally, Sub-Basin 3E and off-site Sub-Basin 3F.4 represent the drainage areas within the Cedar River
buffer that will continue to sheet flow to the river.
Refer to Appendix C for proposed land cover and soil type areas.
PART 4.C: PERFORMANCE STANDARDS
Area-Specific Flow Control Facility requirements are not applicable for this project.
This project is subject to enhanced basic treatment per 1.2.8.1.A of the CORSWDM.
The conveyance system will have sufficient capacity to convey and contain the 25-year peak flow; see
Appendix C for supporting calculations. Due to the presence of the 100-year flood plain on the project site, the
25-year peak flow will be used to design the proposed conveyance system. In the event of a major storm event
(greater than 1-inch within 24 hours), all overflows will discharge to the Cedar River.
PART 4.D: FLOW CONTROL SYSTEM
No flow control system is required, as discussed in Section 2, Core Requirement No. 3 of this report.
PART 4.E: WATER QUALITY SYSTEM
The project’s water quality facilities consist of three Filterra Peak Diversion units. All new pollution-generating
impervious surfaces will be directed to one of the water quality facilities.
The Western Washington Hydrologic Model (WWHM) 2012 was used to size the water quality facilities
following Ecology’s conditions of use. Refer to Part 4.B of this report for the drainage areas to each water
quality facility. Each Filterra water quality (WQ) unit will treat greater than 91% of the total runoff volume.
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Table 4-2: Water Quality Facility Overview
Filterra
Facility Media Bay Size Treated Sub-Basins
WQ Unit No. 1 8 feet x 11.5 feet 3A.1 and 3F.1
WQ Unit No. 2 6 feet x 7.5 feet 3A.2 and 3F.2
WQ Unit No. 3 8 feet x 11.5 feet 3A.3
All supporting documentation for the water quality facilities are provided in Appendix C. This includes the
WWHM report, the Ecology GULD certification for Filterra WQ units, and standard vault details.
No permanent source controls or oil controls are required for this project.
When developed, the area for future commercial development in Sub-Basin 3B will have its own water quality
facility that will tie into the conveyance system associated with this report downstream of proposed the
proposed WQ Unit No. 3. This development will be permitted separately from the scope of work addressed in
this report.
5. Conveyance System Analysis and Design
The existing public stormwater conveyance systems associated with Basins 1 and 2 were not analyzed as part
of this design because the project is not proposing a net increase in impervious surfaces in these basins.
The design approach selects a pipe and slope that has sufficient capacity to convey the 25-year peak flow for
the full sub-basin. MGSFlood software was used to determine the peak flow for each sub-basin and the
Uniform Flow Analysis method was used to calculate the pipe capacity and flow velocities. Refer to Table 5-1
for the selected pipe diameter and slope within each sub-basin. The pipe capacity, 25-year peak flow, and
velocity are also included in Table 5-1. Supporting documentation for peak flow, pipe capacity, and flow
velocities are included in Appendix C.
The two new outfall locations will be stabilized using rock lining in accordance with Section 4.2.2 of the
CORSWDM. Velocities at both outfalls will be less than 5 feet per second during the 25-year peak flow. The
rock lining will consist of quarry spalls with the following gradation: 100% passing the 8-inch square sieve, a
maximum of 40%-60% passing the 3-inch square sieve, and a maximum of 0-10% maximum passing the ¾-
inch square sieve.
The rock lining for the east conveyance outfall will be 1 foot thick, 7.25 feet wide, 8 feet long, and extend 1 foot
above the crown of the outlet pipe. The rock lining for the west conveyance outfall will be 1 foot thick, 7 feet
wide, 8 feet long, and extend 1 foot above the crown of the outlet pipe.
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Table 5-1: Proposed Conveyance Design
Sub-basin Total
Area (ac) Slope
Pipe
Diam
(in)
Manning's
n
Pipe
Capacity
(cfs)
Post-Developed
25-year Flow
(cfs)1
Flow Velocity
at Outfalls
(ft/s)
Sub-Basin 3A.11 1.08 0.5% 12 0.014 2.34 0.54 -
Sub-Basin 3A.22 0.67 0.5% 12 0.014 2.34 0.32 -
Sub-Basin 3A.3 0.78 0.5% 12 0.014 2.34 0.48 -
Sub-Basin 3B3 0.92 0.5% 12 0.014 2.34 0.43 -
Sub-Basin 3C4 3.90 0.5% 12 0.014 2.34 1.91 2.43
Sub-Basin 3D5 4.33 0.6% 12 0.014 2.56 2.32 2.95
Notes:
1. Includes Sub-Basin 3A.1 and off-site Sub-Basin 3F.1.
2. Includes Sub-Basin 3A.2 and off-site Sub-Basin 3F.2.
3. Includes Sub-Basin 3B and off-site 3F.3.
4. Includes Sub-Basin 3A.3, Sub-Basin 3B, Sub-Basin 3C, and off-site Sub-Basin 3F.3.
5. Includes Sub-Basin 3A.1, Sub-Basin 3A.2, Sub-Basin 3D, off-site Sub-Basin 3F.1, off-site Sub-Basin 3F.2.
6. Special Reports and Studies
Once completed, a fluvial geomorphology study prepared by Golder Associates Inc. will be included in the final
version of this report.
7. Other Permits
Section 1.1.3 of the CORSWDM provides other required permits for the project that are included below.
Table 7-1: List of Permits
Agency Permit/Approval
Washington State Department of Transportation Developer/Local Agency Agreement
Access Connection Permit
Washington State Department of Ecology NPDES Construction Stormwater permit
City of Renton
Civil Construction Permit
Clearing, Grading, and Building Permits
Floodplain Development Permit
Shoreline Permits
Aquifer Protection Area Closure Permit
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8. Construction Stormwater Pollution Prevention Plan
(CSWPPP) Analysis and Design
PART A: EROSION AND SEDIMENT CONTROL PLAN ANALYSIS AND DESIGN
Temporary and permanent erosion and sediment control measures will be implemented to meet TESC
requirements per Section D.2.1 of the 2017 CORSWDM.
1. Prior to site clearing or grading, Clearing Limits will be delineated on the temporary erosion and
sediment control (TESC) plans and physically marked on the project site with markers and/or protective
fencing.
2. Temporary and permanent Cover Measures will be provided when necessary during any period of
precipitation to prevent erosion and to provide inlet protection for catch basins.
3. Filter fabric silt fencing or compost socks will provide Perimeter Protection to filter sediment from sheet
flow downstream of all disturbed areas prior to upslope grading.
4. Traffic Area Stabilization methods consist of a stabilized construction entrances, construction staging
areas, and other necessary vehicle stabilization to minimize erosion and tracking of sediment off-site.
5. Sediment Retention will be addressed with the use of a lined sediment pond near the Cedar River. The
sediment pond sizing calculations in accordance with Section D.2.1.5.2 of the CORSWDM are included
in Appendix C.
6. Berms, temporary interceptor swales, and check dams will be implemented as the Surface Water
Collection system to intercept all surface water from disturbed areas and convey the sediment laden
runoff to a sediment pond.
7. Treated runoff will be discharged to an existing catch basin along Maple Valley Highway preceding a
precast Stormfilter facility identified on the TESC plans for Dewatering Control.
8. The Contractor will implement Dust Control mitigation efforts when the wind transport of soil is created
from traffic hazards or weather-related conditions.
9. The site is Flow Control exempt and will not route surface water from disturbed areas to on-site flow
control facilities.
10. The Contractor will implement stormwater pollution prevention measures to mitigate Control Pollutants
by using applicable TESC BMPs.
11. On-Site Construction BMPs and Proposed Stormwater Facilities will be protected and maintained by the
Contractor as indicated in the plans and Operations and Maintenance manual.
12. The TESC plans indicate that BMPs are to be maintained and protected during construction.
13. The project’s general contractor will be required to update the TESC facilities, as needed, to meet on-
site conditions during construction.
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PART B: STORMWATER POLLUTION PREVENTION PLAN (SWPPP ) DESIGN
1. Handling and disposal of all pollutants that occurs on-site, including waste materials, will be conducted in
a manner that does not cause contamination of stormwater.
2. Any chemicals, liquid products, and non-inert wastes present on the site will be covered, protected, and
contained to prevent vandalism and reduce susceptibility to hazards. Secondary containment for on-site
fueling tanks and other materials are required.
3. On-site parking for construction equipment and contractor vehicles will be limited to an on-site
construction staging area as indicated on the TESC plans.
4. Spill prevention measures such as a tire washout area, concrete truck wash area, and drip pans and a
temporary plastic sheet placed beneath the vehicle will be used when conducting maintenance or repair
involving oil changes, hydraulic system drain down, solvent and degreasing cleaning operations, fuel
tank drain down removal, and other activities that may result in discharge or spillage of pollutants.
5. Agricultural chemicals will be applied in a manner and at application rates that will not result in loss of
chemicals to stormwater runoff to avoid overapplication or untimely application of chemicals
and fertilizers.
6. Stormwater shall not cause or contribute to a violation of the water quality standard for pH in the
receiving water.
7. The project’s general contractor will be required to update the Stormwater Pollution Prevention Plan, as
needed, to meet on-site conditions during construction.
9. Bond Quantities, Facility Summaries, and Declaration of
Covenant
The Site Improvement Bond Quantity Worksheet provided by the Community of Economic Development (CED)
is attached to provide a summary of the required construction bond amount and maintenance bond amount for
the proposed improvements. The worksheet has not yet been completed but will be completed prior to
submittal of the Civil Construction Permit. The Facility Summary Reference document is included in
Appendix D.
10. Maintenance and Operations Manual
The stormwater facilities located on-site generally consist of catch basins for collection, storm drainage pipes
for conveyance, rock splash pads for outfall protection, and Contech’s Filterra system for water
quality treatment.
The Maintenance and Operations Manual is intended for the project owner once the project is complete and is
also intended to satisfy the Drainage Review Plan Specifications in Section 2.3.1.1 of the 2017 CORSWDM.
Refer to Appendix A for a copy of the maintenance and operations manual.
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Appendix A
Appendix A
Maintenance and Operations Manual
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Appendix A-1
Cedar River Apartments
City of Renton, WA
Stormwater Maintenance and Operations
Manual
January 2019
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Appendix A-2
Stormwater Maintenance and Operations
Manual
Prepared for:
SRM Development
720 Sixth Street South, Suite 200
Kirkland, WA 98033
Prepared by:
David Schwartz, Principal, Civil Engineer, PE, LEED AP
Maddy Murphy, Civil Design Engineer
KPFF Consulting Engineers
1601 Fifth Avenue, Suite 1600
Seattle, WA 98101
Phone: (206) 622-5822
KPFF Project No. 1700317
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Appendix A-3
1. Stormwater Facility Narrative
The Cedar River Apartment project consists of an approximately 12.48-acre lot located on the north side of
Cedar River in the City of Renton (COR), Washington. The project includes construction of two mixed-use
buildings, paved parking and drive aisles, pedestrian hardscape, sidewalks, landscaping and associated
utilities.
This Maintenance and Operations (MO) Manual is intended for the project owner once the project is complete
and is intended to satisfy the Drainage Review Plan Specifications in Section 2.3.1.1 of the 2017 City of
Renton Surface Water Design Manual (CORSWDM).
SRM Development will be the responsible party for maintenance of the on-site storm system. The contact for
the SRM Development is Tina Swanson, who can be reached at (509) 455-5477. This MO manual will be kept
at a location that can be made available to the City for inspection.
The location of each Best Management Practice (BMP), detail drawings for each BMP, descriptions for all
maintenance tasks and the frequency of each task for each water quality facility, and a sample maintenance
activity log are provided in this OM manual.
The stormwater facilities located on-site generally consist of catch basins for collection, storm drain pipe for
conveyance, and Contech Filterra system units for water quality treatment.
If you are unsure whether a problem exists, please contact the City of Renton Community and Economic
Development (CED) Department at (425) 430-7294.
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Appendix A-4
2. Maintenance Task Description
STORMWATER BMP FACILITIES
Refer to the attached maintenance requirements and Appendix A of the 2017 CORSWDM:
· Catch basins
· Conveyance pipes and ditches
· Energy dissipaters
· Grounds (landscaping)
· Filterra system
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Appendix A-5
NO. 40 – FILTERRA SYSTEM (BY CONTECH)
At a minimum, all stormwater devices must initially be inspected every six months and after every major storm
event (greater than 1 inch within 24 hours). Use the manufacturer’s recommendations, as tailored to the use of
the site and as outlined in the Maintenance and Operation Manual. Maintenance and operations shall conform
to any Ecology-issued use level designation, as applicable.
Filterra system maintenance consists of the removal of trash, sediment, mulch, and the replacement of a fresh
3-inch layer of mulch. After the first year of maintenance by Contech, maintenance should be conducted at
least once per year. Owners must promptly notify the maintenance supplier of any damage to the structure.
Owners should also advise other landscape or maintenance contractors to leave all maintenance to the
supplier (i.e., no pruning or fertilizing) during the first year.
Comments:
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Appendix A-6
STORMWATER FACILITY MAINTENANCE ACTIVITY LOG
1915 Maple Valley Highway
Renton, WA 98057
Name of Inspector(s): ______________________________________________________________
Inspection Date: __________________________________________________________________
Inspection Time: __________________________________________________________________
Approximate Date/Time of Last Rainfall:________________________________________________
Type of Stormwater Facility: _________________________________________________________
Location of Facility on Site (in relation to building or other permanent structures):
Water levels and observations (oil sheen, smell, turbidity, etc.):
Sediment accumulation & record of sediment removal:
Condition of vegetation (height, survival rates, invasive species present, etc.) and record of
replacement and management (mowing, weeding, etc.):
Condition of physical properties such as inlets, outlets, piping, fences, irrigation facilities, and side
slopes. Record damaged items and replacement activities:
Presence of insects or vectors. Record control activities:
Identify safety hazards present. Record resolution activities:
Notes:
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APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS
12/12/2016 2017 City of Renton Surface Water Design Manual
A-48
NO. 39 – RETAINED TREES
MAINTENANCE
COMPONENT
DEFECT OR
PROBLEM
CONDITIONS WHEN MAINTENANCE
IS NEEDED
RESULTS EXPECTED WHEN
MAINTENANCE IS PERFORMED
Tree Dead or declining Dead, damaged, or declining Tree replaced per planting plan or
acceptable substitute
NO. 40 – FILTERRA SYSTEM
MAINTENANCE
COMPONENT
DEFECT OR
PROBLEM
CONDITION WHEN MAINTENANCE
IS NEEDED
RESULTS EXPECTED WHEN
MAINTENANCE IS PERFORMED
In addition to the specific maintenance criteria provided below, all manufacturer’s requirements shall be followed.
Facility – General
Requirements
Life cycle Once per year, except mulch and trash
removal twice per year
Facility is re-inspected and any needed
maintenance performed
Contaminants and
pollution
Any evidence of contaminants or pollution
such as oil, gasoline, concrete slurries, or
paint
Materials removed and disposed of
according to applicable regulations. Source
control BMPs implemented if appropriate.
No contaminants present other than a
surface oil film.
Inlet Excessive sediment or
trash accumulation
Accumulated sediments or trash impair free
flow of water into system
Inlet should be free of obstructions allowing
free distributed flow of water into system
Mulch Cover Trash and floatable
debris accumulation
Excessive trash and/or debris accumulation Minimal trash or other debris on mulch
cover. Mulch cover raked level.
“Ponding” of water on
mulch cover
“Ponding” in unit could be indicative of
clogging due to excessive fine sediment
accumulation or spill of petroleum oils
Stormwater should drain freely and evenly
through mulch cover
Proprietary Filter
Media/
Vegetation Substrate
“Ponding” of water on
mulch cover after
mulch cover has been
maintained
Excessive fine sediment passes the mulch
cover and clogs the filter media/vegetative
substrate
Stormwater should drain freely and evenly
through mulch cover. Replace substrate and
vegetation when needed
Vegetation Plants not growing or in
poor condition
Soil/mulch too wet, evidence of spill,
incorrect plant selection, pest infestation,
and/or vandalism to plants
Plants should be healthy and pest free
Media/mulch too dry Irrigation is required
Plants absent Plants absent Appropriate plants are present
Excessive plant growth Excessive plant growth inhibits facility
function or becomes a hazard for pedestrian
and vehicular circulation and safety
Pruning and/or thinning vegetation maintains
proper plant density. Appropriate plants are
present.
Structure Structure has visible
cracks
Cracks wider than ½ inch
Evidence of soil particles entering the
structure through the cracks
Structure is sealed and structurally sound
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Filterra Owner’s Manual
®
Bioretention Systems
ENGINEERED SOLUTIONS
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Table of Contents
Introduction ................................................................................4
Activation Overview .....................................................................4
Filterra Plant Selection Overview ...................................................6
Warranty Overview ......................................................................6
Routine Maintenance Guidelines...................................................6
Maintenance Visit Procedure .........................................................9
Appendix 1 – Activation Checklist ...............................................12
Appendix 2 – Planting Requirements for Filterra Systems ................13
Enclosed
Local Area Filterra Plant List
®
Bioretention Systems
ENGINEERED SOLUTIONS
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Introduction
Thank you for your purchase of the Filterra® Bioretention System. Filterra is a specially engineered stormwater treatment system
incorporating high performance biofiltration media to remove pollutants from stormwater runoff. The system’s biota (vegetation
and soil microorganisms) then further breakdown and absorb captured pollutants. All components of the system work together
to provide a sustainable long-term solution for treating stormwater runoff.
The Filterra system has been delivered to you with protection in place to resist intrusion of construction related sediment which
can contaminate the biofiltration media and result in inadequate system performance. These protection devices are intended
as a best practice and cannot fully prevent contamination. It is the purchaser’s responsibility to provide adequate measures to
prevent construction related runoff from entering the Filterra system.
Included with your purchase is Activation of the Filterra system by the manufacturer as well as a 1-year warranty from delivery
of the system and 1-year of routine maintenance (mulch replacement, debris removal, and pruning of vegetation) up to twice
during the first year after activation.
Design and Installation
Each project presents different scopes for the use of Filterra systems. Information and help may be provided to the design
engineer during the planning process. Correct Filterra box sizing (by rainfall region) is essential to predict pollutant removal
rates for a given area. The engineer shall submit calculations for approval by the local jurisdiction. The contractor is
responsible for the correct installation of Filterra units as shown in approved plans. A comprehensive installation manual is
available at www.ContechES.com.
Activation Overview
Activation of the Filterra system is a procedure completed by the manufacturer to place the system into working condition. This
involves the following items:
• Removal of construction runoff protection devices
• Planting of the system’s vegetation
• Placement of pretreatment mulch layer using mulch certified for use in Filterra systems.
Activation MUST be provided by the manufacturer to ensure proper site conditions are met for Activation, proper installation of
the vegetation, and use of pretreatment mulch certified for use in Filterra systems.
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Minimum Requirements
The minimum requirements for Filterra Activation are as follows:
1. The site landscaping must be fully stabilized, i.e. full landscaping installed and some grass cover (not just straw and seed) is
required to reduce sediment transport. Construction debris and materials should be removed from surrounding area.
2. Final paving must be completed. Final paving ensures that paving materials will not enter and contaminate the Filterra system
during the paving process, and that the plant will receive runoff from the drainage area, assisting with plant survival for the
Filterra system.
3. Filterra throat opening should be at least 4” in order to ensure adequate capacity for inflow and debris.
An Activation Checklist is included on page 12 to ensure proper conditions are met for Contech to perform the Activation
services. A charge of $500.00 will be invoiced for each Activation visit requested by Customer where Contech determines that the
site does not meet the conditions required for Activation.
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Filterra Plant Selection Overview
A Plant List has been enclosed with this packet highlighting recommended plants for Filterra systems in your area. Keep in mind
that plants are subject to availability due to seasonality and required minimum size for the Filterra system. Plants installed in the
Filterra system are container plants (max 15 gallon) from nursery stock and will be immature in height and spread at Activation.
It is the responsibility of the owner to provide adequate irrigation when necessary to the plant of the Filterra system.
The “Planting Requirements for Filterra Systems” document is included as an appendix and discusses proper selection and care of
the plants within Filterra systems.
Warranty Overview
Refer to the Contech Engineered Solutions LLC Stormwater Treatment System LIMITED WARRANTY for further information. The
following conditions may void the Filterra system’s warranty and waive the manufacturer provided Activation and Maintenance
services:
• Unauthorized activation or performance of any of the items listed in the activation overview
• Any tampering, modifications or damage to the Filterra system or runoff protection devices
• Removal of any Filterra system components
• Failure to prevent construction related runoff from entering the Filterra system
• Failure to properly store and protect any Filterra components (including media and underdrain stone) that may be shipped
separately from the vault
Routine Maintenance Guidelines
With proper routine maintenance, the biofiltration media within the Filterra system should last as long as traditional bioretention
media. Routine maintenance is included by the manufacturer on all Filterra systems for the first year after activation. This includes
a maximum of 2 visits to remove debris, replace pretreatment mulch, and prune the vegetation. More information is provided in
the Operations and Maintenance Guidelines. Some Filterra systems also contain pretreatment or outlet bays. Depending on site
pollutant loading, these bays may require periodic removal of debris, however this is not included in the first year of maintenance,
and would likely not be required within the first year of operation.
These services, as well as routine maintenance outside of the included first year, can be provided by certified maintenance
providers listed on the Contech website. Training can also be provided to other stormwater maintenance or landscape providers.
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Why Maintain?
All stormwater treatment systems require maintenance for effective operation. This necessity is often incorporated in your
property’s permitting process as a legally binding BMP maintenance agreement. Other reasons to maintain are:
• Avoiding legal challenges from your jurisdiction’s maintenance enforcement program.
• Prolonging the expected lifespan of your Filterra media.
• Avoiding more costly media replacement.
• Helping reduce pollutant loads leaving your property.
Simple maintenance of the Filterra is required to continue effective pollutant removal from stormwater runoff before discharge into
downstream waters. This procedure will also extend the longevity of the living biofilter system. The unit will recycle and accumulate
pollutants within the biomass, but is also subjected to other materials entering the inlet. This may include trash, silt and leaves
etc. which will be contained above the mulch layer. Too much silt may inhibit the Filterra’s flow rate, which is the reason for site
stabilization before activation. Regular replacement of the mulch stops accumulation of such sediment.
When to Maintain?
Contech includes a 1-year maintenance plan with each system purchase. Annual included maintenance consists of a maximum
of two (2) scheduled visits. Additional maintenance may be necessary depending on sediment and trash loading (by Owner or at
additional cost). The start of the maintenance plan begins when the system is activated.
Maintenance visits are scheduled seasonally; the spring visit aims to clean up after winter loads including salts and sands while
the fall visit helps the system by removing excessive leaf litter.
It has been found that in regions which receive between 30-50 inches of annual rainfall, (2) two visits are generally required;
regions with less rainfall often only require (1) one visit per annum. Varying land uses can affect maintenance frequency;
e.g. some fast food restaurants require more frequent trash removal. Contributing drainage areas which are subject to new
development wherein the recommended erosion and sediment control measures have not been implemented may require
additional maintenance visits.
Some sites may be subjected to extreme sediment or trash loads, requiring more frequent maintenance visits. This is the reason for
detailed notes of maintenance actions per unit, helping the Supplier and Owner predict future maintenance frequencies, reflecting
individual site conditions.
Owners must promptly notify the (maintenance) Supplier of any damage to the plant(s), which constitute(s) an integral part of the
bioretention technology. Owners should also advise other landscape or maintenance contractors to leave all maintenance to the
Supplier (i.e. no pruning or fertilizing) during the first year.
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Exclusion of Services
Clean up due to major contamination such as oils, chemicals, toxic spills, etc. will result in additional costs and are not covered
under the Supplier maintenance contract. Should a major contamination event occur the Owner must block off the outlet pipe of
the Filterra (where the cleaned runoff drains to, such as drop inlet) and block off the throat of the Filterra. The Supplier should be
informed immediately.
Maintenance Visit Summary
Each maintenance visit consists of the following simple tasks (detailed instructions below).
1. Inspection of Filterra and surrounding area
2. Removal of tree grate and erosion control stones
3. Removal of debris, trash and mulch
4. Mulch replacement
5. Plant health evaluation and pruning or replacement as necessary
6. Clean area around Filterra
7. Complete paperwork
Maintenance Tools, Safety Equipment and Supplies
Ideal tools include: camera, bucket, shovel, broom, pruners, hoe/rake, and tape measure. Appropriate Personal Protective
Equipment (PPE) should be used in accordance with local or company procedures. This may include impervious gloves where the
type of trash is unknown, high visibility clothing and barricades when working in close proximity to traffic and also safety hats and
shoes. A T-Bar or crowbar should be used for moving the tree grates (up to 170 lbs ea.). Most visits require minor trash removal
and a full replacement of mulch. See below for actual number of bagged mulch that is required in each media bay size. Mulch
should be a double shredded, hardwood variety. Some visits may require additional Filterra engineered soil media available from
the Supplier.
Box Length Box Width Filter Surface
Area (ft²)Volume at 3” (ft³)# of 2 ft³ Mulch
Bags
4 4 4 4 2
6 4 6 6 3
8 4 8 8 4
6 6 9 9 5
8 6 12 12 6
10 6 15 15 8
12 6 18 18 9
13 7 23 23 12
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1. Inspection of Filterra and surrounding area
• Record individual unit before maintenance with photograph (numbered).
Record on Maintenance Report (see example in this document) the following:
2. Removal of tree grate and erosion control stones
• Remove cast iron grates for access into Filterra box.
• Dig out silt (if any) and mulch and remove trash & foreign items.
3. Removal of debris, trash and mulch
• After removal of mulch and debris, measure distance from the top of the
Filterra engineered media soil to the top of the top slab. Compare the
measured distance to the distance shown on the approved Contract Drawings
for the system. Add Filterra media (not top soil or other) to bring media up as
needed to distance indicated on drawings.
Record on Maintenance Report the following:
Standing Water yes | no
Damage to Box Structure yes | no
Damage to Grate yes | no
Is Bypass Clear yes | no
If yes answered to any of these observations, record with
close-up photograph (numbered).
Record on Maintenance Report the following:
Silt/Clay yes | no
Cups/ Bags yes | no
Leaves yes | no
Buckets Removed ________
Record on Maintenance Report the following:
Distance to Top of Top Slab (inches) ________
Inches of Media Added ________
Maintenance Visit Procedure
Keep sufficient documentation of maintenance actions to predict location specific maintenance frequencies and needs. An
example Maintenance Report is included in this manual.
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4. Mulch replacement
• Add double shredded mulch evenly across the entire unit to a depth of 3”.
• Refer to Filterra Mulch Specifications for information on acceptable sources.
• Ensure correct repositioning of erosion control stones by the Filterra inlet to
allow for entry of trash during a storm event.
• Replace Filterra grates correctly using appropriate lifting or moving tools,
taking care not to damage the plant.
5. Plant health evaluation and pruning or replacement
as necessary
• Examine the plant’s health and replace if necessary.
• Prune as necessary to encourage growth in the correct directions
6. Clean area around Filterra
• Clean area around unit and remove all refuse to be disposed of appropriately.
7. Complete paperwork
• Deliver Maintenance Report and photographs to appropriate location
(normally Contech during maintenance contract period).
• Some jurisdictions may require submission of maintenance reports in
accordance with approvals. It is the responsibility of the Owner to comply with
local regulations.
Record on Maintenance Report the following:
Height above Grate _____________________(ft)
Width at Widest Point _____________________(ft)
Health healthy | unhealthy
Damage to Plant yes | no
Plant Replaced yes | no
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Maintenance Checklist
Filterra Inspection & Maintenance Log
Filterra System Size/Model: _____________________________Location: ____________________________________________
Drainage
System Failure Problem Conditions to Check Condition that Should Exist Actions
Inlet
Excessive
sediment or trash
accumulation.
Accumulated sediments or
trash impair free flow of water
into Filterra.
Inlet should be free of
obstructions allowing free
distributed flow of water into
Filterra.
Sediments and/or trash should
be removed.
Mulch Cover Trash and floatable
debris accumulation.
Excessive trash and/or debris
accumulation.
Minimal trash or other debris
on mulch cover.
Trash and debris should be
removed and mulch cover raked
level. Ensure bark nugget mulch
is not used.
Mulch Cover “Ponding” of water
on mulch cover.
“Ponding” in unit could be
indicative of clogging due
to excessive fine sediment
accumulation or spill of
petroleum oils.
Stormwater should drain
freely and evenly through
mulch cover.
Recommend contact
manufacturer and replace mulch
as a minimum.
Vegetation Plants not growing
or in poor condition.
Soil/mulch too wet, evidence of
spill. Incorrect plant selection.
Pest infestation. Vandalism to
plants.
Plants should be healthy and
pest free.Contact manufacturer for advice.
Vegetation Plant growth
excessive.
Plants should be appropriate
to the species and location of
Filterra.
Trim/prune plants in accordance
with typical landscaping and
safety needs.
Structure Structure has visible
cracks.
Cracks wider than 1/2 inch
or evidence of soil particles
entering the structure through
the cracks.
Vault should be repaired.
Maintenance is ideally to be performed twice annually.
Date
Mulch &
Debris
Removed
Depth of
Mulch
Added
Mulch
Brand
Height of
Vegetation
Above
Grate
Vegetation
Species
Issues with
System Comments
1/1/17 5 – 5 gal
Buckets 3”
Lowe’s
Premium
Brown Mulch
4’Galaxy
Magnolia
- Standing water in
downstream structure
- Removed blockage in downstream
structure
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Appendix 1 – Filterra® Activation Checklist
Project Name: ________________________________________Company: ______________________________________________
Site Contact Name: _______________________________________Site Contact Phone/Email: ____________________________
Site Owner/End User Name: _________________________Site Owner/End User Phone/Email: ____________________________
Preferred Activation Date: ___________________________________(provide 2 weeks minimum from date this form is submitted)
Site
Designation System Size
Final Pavement
/ Top Coat
Complete
Landscaping
Complete
/ Grass
Emerging
Construction
materials /
Piles / Debris
Removed
Throat
Opening
Measures 4”
Min. Height
Plant Species
Requested
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
NOTE: A charge of $500.00 will be invoiced for each Activation visit requested by Customer where Contech determines that the
site does not meet the conditions required for Activation. ONLY Contech authorized representatives can perform Activation of
Filterra systems; unauthorized Activations will void the system warranty and waive manufacturer supplied Activation and 1st Year
Maintenance.
Attach additional sheets as necessary.
Signature Date
ENGINEERED SOLUTIONS
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Appendix 2 – Planting Requirements for Filterra® Systems
Plant Material Selection
• Select plant(s) as specified in the engineering plans and specifications.
• Select plant(s) with full root development but not to the point where root bound.
• Use local nursery container plants only. Ball and burlapped plants are not permitted.
• For precast Filterra systems with a tree grate, plant(s) must not have scaffold limbs at
least 14 inches from the crown due to spacing between the top of the mulch and the
tree grate. Lower branches can be pruned away provided there are sufficient scaffold
branches for tree or shrub development.
• For precast Filterra systems with a tree grate, at the time of installation, it is required
that plant(s) must be at least 6” above the tree grate opening at installation for all
Filterra configurations. This DOES NOT apply to Full Grate Cover designs.
• Plant(s) shall not have a mature height greater than 25 feet.
• For standard 21” media depth, a 7 – 15 gallon container size shall be used. Media less than 21” (Filterra boxes only) will
require smaller container plants.
• For precast Filterra systems, plant(s) should have a single trunk at installation, and pruning may be necessary at activation
and maintenance for some of the faster growing species, or species known to produce basal sprouts.
Plant Installation
• During transport protect the plant leaves from wind and excessive jostling.
• Prior to removing the plant(s) from the container, ensure the soil moisture is sufficient to maintain the integrity of the root ball.
If needed, pre-wet the container plant.
• Cut away any roots which are growing out of the container drain holes. Plants with excessive root growth from the drain holes
should be rejected.
• Plant(s) should be carefully removed from the pot by gently pounding on the sides of the container with the fist to loosen root
ball. Then carefully slide out. Do not lift plant(s) by trunk as this can break roots and cause soil to fall off. Extract the root ball
in a horizontal position and support it to prevent it from breaking apart. Alternatively the pot can be cut away to minimize
root ball disturbance.
• Remove any excess soil from above the root flare after removing plant(s) from container.
• Excavate a hole with a diameter 4” greater than the root ball, gently place the plant(s).
• If plant(s) have any circling roots from being pot bound, gently tease them loose without breaking them.
• If root ball has a root mat on the bottom, it should be shaved off with a knife just above the mat line.
• Plant the tree/shrub/grass with the top of the root ball 1” above surrounding media to allow for settling.
• All plants should have the main stem centered in the tree grate (where applicable) upon completion of installation.
• With all trees/shrubs, remove dead, diseased, crossed/rubbing, sharply crotched branches or branches growing excessively
long or in wrong direction compared to majority of branches.
• To prevent transplant shock (especially if planting takes place in the hot season), it may be necessary to prune some of
the foliage to compensate for reduced root uptake capacity. This is accomplished by pruning away some of the smaller
secondary branches or a main scaffold branch if there are too many. Too much foliage relative to the root ball can dehydrate
and damage the plant.
• Plant staking may be required.
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Mulch Installation
• Only mulch that has been meeting Contech Engineered Solutions’ mulch specifications can be used in the Filterra system.
• Mulch must be applied to a depth of 3” evenly over the surface of the media.
Irrigation Requirements
• Each Filterra system must receive adequate irrigation to ensure survival of the living system during periods of drier weather.
• Irrigation sources include rainfall runoff from downspouts and/or gutter flow, applied water through the tree grate or in some
cases from an irrigation system with emitters installed during construction.
• At Activation: Apply about one (cool climates) to two (warm climates) gallons of water per inch of trunk diameter over the
root ball.
• During Establishment: In common with all plants, each Filterra plant will require more frequent watering during the
establishment period. One inch of applied water per week for the first three months is recommended for cooler climates (2
to 3 inches for warmer climates). If the system is receiving rainfall runoff from the drainage area, then irrigation may not be
needed. Inspection of the soil moisture content can be evaluated by gently brushing aside the mulch layer and feeling the
soil. Be sure to replace the mulch when the assessment is complete. Irrigate as needed**.
• Established Plants: Established plants have fully developed root systems and can access the entire water column in the media.
Therefore irrigation is less frequent but requires more applied water when performed. For a mature system assume 3.5
inches of available water within the media matrix. Irrigation demand can be estimated as 1” of irrigation demand per week.
Therefore if dry periods exceed 3 weeks, irrigation may be required. It is also important to recognize that plants which are
exposed to windy areas and reflected heat from paved surfaces may need more frequent irrigation. Long term care should
develop a history which is more site specific.
** Five gallons per square yard approximates 1 inch of water Therefore for a 6’ by 6’ Filterra approximately 20-60 gallons of
water is needed. To ensure even distribution of water it needs to be evenly sprinkled over the entire surface of the filter bed, with
special attention to make sure the root ball is completely wetted. NOTE: if needed, measure the time it takes to fill a five gallon
bucket to estimate the applied water flow rate then calculate the time needed to irrigate the Filterra. For example, if the flow rate
of the sprinkler is 5 gallons/minute then it would take 12 minutes to irrigate a 6’ by 6’ filter.
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© 2018 Contech Engineered Solutions LLC, a QUIKRETE Company
9025 Centre Pointe Drive, Suite 400
West Chester, OH 45069
info@conteches.com | 800-338-1122
www.ContechES.com
ALL RIGHTS RESERVED. PRINTED IN THE USA.
NOTHING IN THIS CATALOG SHOULD BE CONSTRUED AS A WARRANTY. APPLICATIONS SUGGESTED HEREIN ARE DESCRIBED
ONLY TO HELP READERS MAKE THEIR OWN EVALUATIONS AND DECISIONS, AND ARE NEITHER GUARANTEES NOR
WARRANTIES OF SUITABILITY FOR ANY APPLICATION. CONTECH MAKES NO WARRANTY WHATSOEVER, EXPRESS OR IMPLIED,
RELATED TO THE APPLICATIONS, MATERIALS, COATINGS, OR PRODUCTS DISCUSSED HEREIN. ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND ALL IMPLIED WARRANTIES OF FITNESS FOR ANY PARTICULAR PURPOSE ARE DISCLAIMED BY CONTECH.
SEE CONTECH’S CONDITIONS OF SALE (AVAILABLE AT WWW.CONTECHES.COM/COS) FOR MORE INFORMATION.
®
Bioretention Systems
ENGINEERED SOLUTIONS
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
AAPLAN VIEWSECTION A-A(STANDARD DEPTH SHOWN)21" FILTERRA MEDIA, TYPPROVIDED BY CONTECH6" UNDERDRAINSTONE LAYER, TYPPROVIDED BY CONTECH3" MULCH LAYER, TYPPROVIDED BY CONTECHVAULT LENGTH6" (STD)12" (DEEP)4'-1" (STD)4'-7" (DEEP)7"Ø CLEANOUTTREE GRATEVAULT WIDTHOUTLET PIPENOT BY CONTECH(LOCATION VARIES)2"Ø IRRIGATION PORT(TYP 3 PLACES)UNDERDRAIN*CURBINLET*ALT CURBINLET LOC2'-0"MINMEDIA BAYPLANT PROVIDED BY CONTECHTREE FRAME AND GRATECAST INTO TOP SLABCLEAN OUT FRAME ANDCOVER CAST INTO TOP SLAB2"Ø IRRIGATION PORT(TYP 3 PLACES)FLOWKITOUTLET PIPENOT BY CONTECH(LOCATION VARIES)*INLET PIPENOT BY CONTECH(LOCATION VARIES)TRANSFER OPENING4" x 15" ON 4' WIDE VAULTS4" x 20" ON 6'-8' WIDE VAULTSOUTLET ACCESSINLETACCESSTOP SLAB*INLET PIPENOT BY CONTECH(LOCATION VARIES)*CURBINLET 2'-7"INLET BAYPERMANENTSETTLINGPOOL ELEV.ENERGYDISSIPATIONROCKSCURB AND GUTTER, TYP.(NOT BY CONTECH)SEE CURB INLET DETAILALTERNATE ORIENTATIONCURB INLET DETAILCURB AND GUTTER, TYP(NOT BY CONTECH)STREETFTPD STANDARD HEIGHT CONFIGURATIONDESIGNATION(OPTIONS: -P,-T, -PT)AVAILABILITYMEDIABAY SIZEVAULTSIZE(W x L)WEIRLENGTH/MAX CURBOPENING*MAXBYPASSFLOW(CFS)INLET/OUTLETACCESSDIATREEGRATEQTY &SIZEFTPD0404N/A CA4 x 44 x 61'-8"1.412"/12"(1) 3' x 3'FTPD04045CA ONLY4 x 4.54 x 6.51'-8"1.412"/12"(1) 3' x 3'FTPD0406N/A MID-ATL4 x 64 x 81'-8"1.412"/12"(1) 3' x 3'FTPD045058MID-ATL ONLY4.5 x 5.834.5 x 7.831'-8"1.412"/12"(1) 3' x 3'FTPD0604ALL6 x 46 x 61'-8"1.412"/12"(1) 3' x 3'FTPD0606ALL6 x 66 x 81'-8"1.412"/12"(1) 3' x 3'FTPD0608ALL6 x 86 x 101'-8"1.412"/12"(1) 4' x 4'FTPD0610ALL6 x 106 x 121'-8"1.412"/12"(1) 4' x 4'FTPD0710ALL7 x 107 x 132'-6"2.124"/24"(1) 4' x 4'FTPD08105ALL8 x 10.58 x 143'-0"2.524"/24"(1) 4' x 4'FTPD08125ALL8 x 12.58 x 163'-0"2.524"/24"(2) 4' x 4'N/A = NOT AVAILABLE800-338-1122 513-645-7000 513-645-7993 FAX9025 Centre Pointe Dr., Suite 400, West Chester, OH 45069I:\STORMWATER\COMMOPS\54 FILTERRA\40 STANDARD DRAWINGS\FTPD - FILTERRA PEAK DIVERSION\FTPD\LAYOUT DETAILS\DWG\JW EDITFTPD - FILTERRA PEAK DIVERSION CONFIG DTL.DWG 10/4/2018 11:08 AM
FILTERRA PEAK DIVERSION (FTPD)CONFIGURATION DETAILwww.ContechES.comTHIS PRODUCT MAY BE PROTECTED BY ONE OR MORE OFTHE FOLLOWING U.S. PATENTS: 6,277,274; 6,569,321;7,625,485; 7,425,261; 7,833,412; RELATED FOREIGN PATENTS.®INTERNAL PIPE CONFIGURATION MAY VARYDEPENDING UPON OUTLET LOCATION.The design and information shown on this drawing is provided as a service to the project owner, engineer and contractor by Contech Engineered Solutions LLC or one of its affiliated companies ("Contech"). Neither this drawing, nor any part thereof, may be used, reproduced or modified in any mannerwithout the prior written consent of Contech. Failure to comply is done at the user's own risk and Contech expressly disclaims any liability or responsibility for such use. If discrepancies between the supplied information upon which the drawing is based and actual field conditions are encountered as sitework progresses, these discrepancies must be reported to Contech immediately for re-evaluation of the design. Contech accepts no liability for designs based on missing, incomplete or inaccurate information supplied by others.FTPD-D DEEP OPTION CONFIGURATIONDESIGNATION(OPTIONS: -P,-T, -PT)AVAILABILITYMEDIABAY SIZEVAULTSIZE(W x L)WEIRLENGTH/MAX CURBOPENING*MAXBYPASSFLOW(CFS)INLET/OUTLETACCESSDIATREEGRATEQTY &SIZEFTPD0404-DN/A CA4 x 44 x 61'-8"4.612"/12"(1) 3' x 3'FTPD04045-DCA ONLY4 x 4.54 x 6.51'-8"4.612"/12"(1) 3' x 3'FTPD0406-DN/A MID-ATL4 x 64 x 81'-8"4.612"/12"(1) 3' x 3'FTPD045058-DMID-ATL ONLY4.5 x 5.834.5 x 7.831'-8"4.612"/12"(1) 3' x 3'FTPD0604-DALL6 x 46 x 61'-8"4.612"/12"(1) 3' x 3'FTPD0606-DALL6 x 66 x 81'-8"4.612"/12"(1) 3' x 3'FTPD0608-DALL6 x 86 x 101'-8"4.612"/12"(1) 4' x 4'FTPD0610-DALL6 x 106 x 121'-8"4.612"/12"(1) 4' x 4'FTPD0710-DALL7 x 107 x 132'-6"6.824"/24"(1) 4' x 4'FTPD08105-DALL8 x 10.58 x 143'-0"8.224"/24"(1) 4' x 4'FTPD08125-DALL8 x 12.58 x 163'-0"8.224"/24"(2) 4' x 4'N/A = NOT AVAILABLE*IF REQUIRED*IF REQUIRED*MAX BYPASS FLOW IS INTERNAL WEIR FLOW . SITE SPECIFIC ANALYSIS IS REQUIRED TO DETERMINE CURB INLET FLOW CAPACITYDocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
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Cedar River Apartments – SRM Development
Appendix B
Appendix B
Site Improvement Plans
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BASIS OF BEARINGS
SURVEYOR'S NOTES
VERTICAL DATUM:
BENCHMARK:
SURVEY LEGEND:
A PORTION OF THE NORTHWEST CORNER OF THE SOUTHWEST QUARTER,
THE NORTHWEST QUARTER AND THE NORTHEAST QUARTER OF THE SOUTHEAST QUARTER
ALL IN SECTION 17, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M.
CITY OF RENTON, KING COUNTY, WASHINGTON
CEDAR RIVER APARTMENTS PROJECT
VICINITY MAP
PROPOSED LEGEND
ABBREVIATIONS
SURVEY BY:
CITY OF
RENTON
IN COMPLIANCE WITH CITY OF RENTON STANDARDS PR:A-NNNNNNN
CEDAR RIVER APARTMENTSC:LUA:CEDAR RIVER APARTMENTSCEDAR RIVER APARTMENTS PROJECT
1915 MAPLE VALLEY HWY, RENTON, WA 98055AAANNNNNNN1601 5th Avenue, Suite 1600
Seattle, WA 98101
206.622.5822
www.kpff.com
R
Call 811two business days
before you dig
NOT FOR CONSTRUCTION
SHORELINE DEVELOPMENT PERMIT/MASTER SITE PLAN APPROVAL
CIVIL COVER SHEETXDocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CITY OF
RENTON
IN COMPLIANCE WITH CITY OF RENTON STANDARDS PR:A-NNNNNNN
CEDAR RIVER APARTMENTSC:LUA:CEDAR RIVER APARTMENTSCEDAR RIVER APARTMENTS PROJECT
1915 MAPLE VALLEY HWY, RENTON, WA 98055AAANNNNNNN1601 5th Avenue, Suite 1600
Seattle, WA 98101
206.622.5822
www.kpff.com
R
Call 811two business days
before you dig
NOT FOR CONSTRUCTION
SHORELINE DEVELOPMENT PERMIT/MASTER SITE PLAN APPROVAL
GRADING AND STORM DRAINAGE OVERALL PLANXPROPOSED LEGEND GENERAL NOTES
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CITY OF
RENTON
IN COMPLIANCE WITH CITY OF RENTON STANDARDS PR:A-NNNNNNN
CEDAR RIVER APARTMENTSC:LUA:CEDAR RIVER APARTMENTSCEDAR RIVER APARTMENTS PROJECT
1915 MAPLE VALLEY HWY, RENTON, WA 98055AAANNNNNNN1601 5th Avenue, Suite 1600
Seattle, WA 98101
206.622.5822
www.kpff.com
R
Call 811two business days
before you dig
NOT FOR CONSTRUCTION
SHORELINE DEVELOPMENT PERMIT/MASTER SITE PLAN APPROVAL
UTILITY OVERALL PLANXPROPOSED LEGEND
GENERAL NOTES
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
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Cedar River Apartments – SRM Development
Appendix C
Appendix C
TESC, Water Quality, and Conveyance Calculations an d Design Analysis
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TESC SEDIMENT POND SIZING CALCULATIONS
Construction limit of work area = 559,509 ft2 = 12.845 acres
2-Year Peak Flow = Q2 = 4.899 cfs
10-Year Peak Flow = Q10 = 7.168 cfs
100-Year Peak Flow = Q100 = 12.551 cfs
Equations per 2017 City of Renton Surface Water Design Manual, Section D.2.1.5.2
Pond Dimensions:
ft2
(Required surface area at top of the riser pipe)
L: W = 3:1
L ~ 211 feet
W ~ 71 feet
L*W = 14,981 ft2
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—————————————————————————————————
MGS FLOOD
PROJECT REPORT
Program Version: MGSFlood 4.46
Program License Number: 200410007
Project Simulation Performed on: 12/13/2018 1:09 PM
Report Generation Date: 12/13/2018 1:10 PM
—————————————————————————————————
Input File Name: Sediment Pond.fld
Project Name: SRM Renton
Analysis Title:
Comments:
———————————————— PRECIPITATION INPUT ————————————————
Computational Time Step (Minutes): 15
Extended Precipitation Time Series Selected
Climatic Region Number: 3
Full Period of Record Available used for Routing
Precipitation Station : 95004005 Puget West 40 in_5min 10/01/1939-10/01/2097
Evaporation Station : 951040 Puget West 40 in MAP
Evaporation Scale Factor : 0.750
HSPF Parameter Region Number: 1
HSPF Parameter Region Name : USGS Default
********** Default HSPF Parameters Used (Not Modified by User) ***************
********************** WATERSHED DEFINITION ***********************
Predevelopment/Post Development Tributary Area Summary
Predeveloped Post Developed
Total Subbasin Area (acres) 12.845 12.845
Area of Links that Include Precip/Evap (acres) 0.000 0.000
Total (acres) 12.845 12.845
----------------------SCENARIO: PREDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 1 ----------
-------Area (Acres) --------
Impervious 12.845
----------------------------------------------
Subbasin Total 12.845
----------------------SCENARIO: POSTDEVELOPED
Number of Subbasins: 1
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
---------- Subbasin : Subbasin 1 ----------
-------Area (Acres) --------
Impervious 12.845
----------------------------------------------
Subbasin Total 12.845
***********Water Quality Facility Data *************
----------------------SCENARIO: PREDEVELOPED
Number of Links: 0
----------------------SCENARIO: POSTDEVELOPED
Number of Links: 0
***********Compliance Point Results *************
Scenario Predeveloped Compliance Subbasin: Subbasin 1
Scenario Postdeveloped Compliance Subbasin: Subbasin 1
*** Point of Compliance Flow Frequency Data ***
Recurrence Interval Computed Using Gringorten Plotting Position
Predevelopment Runoff Postdevelopment Runoff
Tr (Years) Discharge (cfs) Tr (Years) Discharge (cfs)
----------------------------------------------------------------------------------------------------------------------
2-Year 4.899 2-Year 4.899
5-Year 6.375 5-Year 6.375
10-Year 7.168 10-Year 7.168
25-Year 8.349 25-Year 8.349
50-Year 10.780 50-Year 10.780
100-Year 12.551 100-Year 12.551
200-Year 12.919 200-Year 12.919
** Record too Short to Compute Peak Discharge for These Recurrence Intervals
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November 2016
GENERAL USE LEVEL DESIGNATION FOR BASIC (TSS), ENHANCED,
PHOSPHORUS & OIL TREATMENT
For
Americast Filterra®
Ecology’s Decision:
Based on Americast’s submissions, including the Final Technical Evaluation Reports, dated
March 27, 2014 and December 2009, and additional information provided to Ecology dated
October 9, 2009, Ecology hereby issues the following use level designations:
1. A General Use Level Designation for Basic, Enhanced, Phosphorus, and Oil Treatment at the
following water quality design hydraulic loading rates:
Treatment Hydraulic Conductivity*
(in/hr) for use in Western
Washington Sizing
Infiltration Rate (in/hr) for
use in eastern Washington
Sizing
Basic 70.92 100
Phosphorus 70.92 100
Oil 35.46 50
Enhanced 24.82 35
*calculated based on listed infiltration rate and a hydraulic gradient of 1.41 inch/inch (2.55 ft
head with 1.80 ft media).
2. The Filterra® unit is not appropriate for oil spill-control purposes.
3. Ecology approves the Filterra® units for treatment at the hydraulic loading rates listed above,
to achieve the maximum water quality design flow rate. Calculate the water quality design
flow rates using the following procedures:
Western Washington: for treatment installed upstream of detention or retention, the water
quality design flow rate is the peak 15-minute flow rate as calculated using the sand filter
module in the latest version of the Western Washington Hydrology Model or other
Ecology-approved continuous runoff model. The model must indicate the unit is capable
of processing 91 percent of the influent runoff file.
Eastern Washington: For treatment installed upstream of detention or retention, the water
quality design flow rate is the peak 15-minute flow rate as calculated using one of the
three flow rate based methods described in Chapter 2.2.5 of the Stormwater Management
Manual for Eastern Washington (SWMMEW) or local manual.
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Entire State: For treatment installed downstream of detention, the water quality design
flow rate is the full 2-year release rate of the detention facility.
4. This General Use Level Designation has no expiration date but Ecology may revoke or
amend the designation, and is subject to the conditions specified below.
Ecology’s Conditions of Use:
Filterra® units shall comply with these conditions shall comply with the following conditions:
1. Design, assemble, install, operate, and maintain the Filterra® units in accordance with
applicable Americast Filterra® manuals, document, and the Ecology Decision.
2. Each site plan must undergo Americast Filterra® review before Ecology can approve the unit
for site installation. This will ensure that site grading and slope are appropriate for use of a
Filterra® unit.
3. Filterra® media shall conform to the specifications submitted to and approved by Ecology.
4. Maintenance includes removing trash, degraded mulch, and accumulated debris from the
filter surface and replacing the mulch layer. Use inspections to determine the site-specific
maintenance schedules and requirements. Follow maintenance procedures given in the most
recent version of the Filterra® Operation and Maintenance Manual.
5. Maintenance: The required maintenance interval for stormwater treatment devices is often
dependent upon the degree of pollutant loading from a particular drainage basin. Therefore,
Ecology does not endorse or recommend a “one size fits all” maintenance cycle for a
particular model/size of manufactured filter treatment device.
Filterra® designs their systems for a target maintenance interval of 6 months.
Maintenance includes removing accumulated sediment and trash from the surface area of
the media, removing the mulch above the media, replacing the mulch, providing plant
health evaluation, and pruning the plant if deemed necessary.
Conduct maintenance following manufacturer’s guidelines.
6. Filterra® units come in standard sizes.
7. The minimum size filter surface-area for use in western Washington is determined by using
the sand filter module in the latest version of WWHM or other Ecology approved continuous
runoff model for western Washington. Model inputs include
a) Filter media depth: 1.8 feet
b) Effective Ponding Depth: 0.75 feet (This is equivalent to the 6-inch clear zone
between the top of the mulch and the bottom of the slab plus 3-inches of mulch.)
c) Side slopes: Vertical
d) Riser height: 0.70 feet
e) Filter Hydraulic Conductivity: Use the Hydraulic Conductivity as listed in the table
above (use the lowest applicable hydraulic conductivity depending on the level of
treatment required) under Ecology’s Decision, above.
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8. The minimum size filter surface-area for use in eastern Washington is determined by using
the design water quality flow rate (as determined in item 3, above) and the Infiltration Rate
from the table above (use the lowest applicable Infiltration Rate depending on the level of
treatment required). Calculate the required area by dividing the water quality design flow rate
(cu-ft/sec) by the Infiltration Rate (converted to ft/sec) to obtain required surface area (sq ft)
of the Filterra unit.
9. Discharges from the Filterra® units shall not cause or contribute to water quality standards
violations in receiving waters.
Approved Alternate Configurations
Filterra® Internal Bypass - Pipe (FTIB-P)
1. The Filterra® Internal Bypass – Pipe allows for piped-in flow from area drains, grated inlets,
trench drains, and/or roof drains. Design capture flows and peak flows enter the structure
through an internal slotted pipe. Filterra® inverted the slotted pipe to allow design flows to
drop through to a series of splash plates that then disperse the design flows over the top
surface of the Filterra® planter area. Higher flows continue to bypass the slotted pipe and
convey out the structure.
2. To select a FTIB-P unit, the designer must determine the size of the standard unit using the
sizing guidance described above.
Filterra® Internal Bypass – Curb (FTIB-C)
1. The Filterra® Internal Bypass –Curb model (FTIB-C) incorporates a curb inlet, biofiltration
treatment chamber, and internal high flow bypass in one single structure. Filterra® designed
the FTIB-C model for use in a “Sag” or “Sump” condition and will accept flows from both
directions along a gutter line. An internal flume tray weir component directs treatment flows
entering the unit through the curb inlet to the biofiltration treatment chamber. Flows in
excess of the water quality treatment flow rise above the flume tray weir and discharge
through a standpipe orifice; providing bypass of untreated peak flows. Americast
manufactures the FTIB-C model in a variety of sizes and configurations and you may use the
unit on a continuous grade when a single structure providing both treatment and high flow
bypass is preferred. The FTIB-C model can also incorporate a separate junction box chamber
to allow larger diameter discharge pipe connections to the structure.
2. To select a FTIB-C unit, the designer must determine the size of the standard unit using the
sizing guidance described above.
Filterra® Shallow
1. The Filterra® Shallow provides additional flexibility for design engineers and designers in
situations where there is limited depth and various elevation constraints to applying a
standard Filterra® configuration. Engineers can design this system up to six inches shallower
than any of the previous Filterra unit configurations noted above.
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2. Ecology requires that the Filterra® Shallow provide a contact time equivalent to that of the
standard unit. This means that with a smaller depth of media, the surface area must increase.
3. To select a Filterra® Shallow System unit, the designer must first identify the size of the
standard unit using the modeling guidance described above.
4. Once you establish the size of the standard Filterra® unit using the sizing technique described
above, use information from the following table to select the appropriate size Filterra®
Shallow System unit.
Shallow Unit Basic, Enhanced, and Oil Treatment Sizing
Standard Depth Equivalent Shallow Depth
4x4 4x6 or 6x4
4x6 or 6x4 6x6
4x8 or 8x4 6x8 or 8x6
6x6 6x10 or 10x6
6x8 or 8x6 6x12 or 12x6
6x10 or 10x6 13x7
Notes:
1. Shallow Depth Boxes are less than the standard depth of 3.5 feet but no less
than 3.0 feet deep (TC to INV).
Applicant: Filterra® Bioretention Systems, division of Contech
Engineered Solutions, LLC.
Applicant’s Address: 11815 NE Glenn Widing Drive
Portland, OR 97220
Application Documents:
State of Washington Department of Ecology Application for Conditional Use
Designation, Americast (September 2006)
Quality Assurance Project Plan Filterra® Bioretention Filtration System Performance
Monitoring, Americast (April 2008)
Quality Assurance Project Plan Addendum Filterra® Bioretention Filtration System
Performance Monitoring, Americast (June 2008)
Draft Technical Evaluation Report Filterra® Bioretention Filtration System Performance
Monitoring, Americast (August 2009)
Final Technical Evaluation Report Filterra® Bioretention Filtration System Performance
Monitoring, Americast (December 2009)
Technical Evaluation Report Appendices Filterra® Bioretention Filtration System
Performance Monitoring, Americast, August 2009
Memorandum to Department of Ecology Dated October 9, 2009 from Americast, Inc. and
Herrera Environmental Consultants
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Quality Assurance Project Plan Filterra® Bioretention System Phosphorus treatment and
Supplemental Basic and Enhanced Treatment Performance Monitoring, Americast
(November 2011)
Filterra® letter August 24, 2012 regarding sizing for the Filterra® Shallow System.
University of Virginia Engineering Department Memo by Joanna Crowe Curran, Ph. D
dated March 16, 2013 concerning capacity analysis of Filterra® internal weir inlet tray.
Terraphase Engineering letter to Jodi Mills, P.E. dated April 2, 2013 regarding
Terraflume Hydraulic Test, Filterra® Bioretention System and attachments.
Technical Evaluation Report, Filterra® System Phosphorus Treatment and Supplemental
Basic Treatment Performance Monitoring. March 27th, 2014.
Applicant’s Use Level Request:
General Level Use Desi gnation for Basic, Enhanced, Phosphorus, and Oil Treatment.
Applicant’s Performance Claims:
Field-testing and laboratory testing show that the Filterra® unit is promising as a stormwater
treatment best management practice and can meet Ecology’s performance goals for basic,
enhanced, phosphorus, and oil treatment.
Findings of Fact:
Field Testing 2013
1. Filterra® completed field-testing of a 6.5 ft x 4 ft. unit at one site in Bellingham,
Washington. Continuous flow and rainfall data collected from January 1, 2013 through
July 23, 2013 indicated that 59 storm events occurred. The monitoring obtained water
quality data from 22 storm events. Not all the sampled storms produced information that
met TAPE criteria for storm and/or water quality data.
2. The system treated 98.9 percent of the total 8-month runoff volume during the testing
period. Consequently, the system achieved the goal of treating 91 percent of the volume
from the site. Stormwater runoff bypassed during four of the 59 storm events.
3. Of the 22 sampled events, 18 qualified for TSS analysis (influent TSS concentrations
ranged from 25 to 138 mg/L). The data were segregated into sample pairs with influent
concentration greater than and less than 100 mg/L. The UCL95 mean effluent
concentration for the data with influent less than 100 mg/L was 5.2 mg/L, below the 20-
mg/L threshold. Although the TAPE guidelines do not require an evaluation of TSS
removal efficiency for influent concentrations below 100 mg/L, the mean TSS removal
for these samples was 90.1 percent. Average removal of influent TSS concentrations
greater than 100 mg/L (three events) was 85 percent. In addition, the system consistently
exhibited TSS removal greater than 80 percent at flow rates at a 100 inches per hour
[in/hr] infiltration rate and was observed at 150 in/hr.
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4. Ten of the 22 sampled events qualified for TP analysis. Americast augmented the dataset
using two sample pairs from previous monitoring at the site. Influent TP concentrations
ranged from 0.11 to 0.52 mg/L. The mean TP removal for these twelve events was 72.6
percent. The LCL95 mean percent removal was 66.0, well above the TAPE requirement
of 50 percent. Treatment above 50 percent was evident at 100 in/hr infiltration rate and as
high as 150 in/hr. Consequently, the Filterra® test system met the TAPE Phosphorus
Treatment goal at 100 in/hr. Influent ortho-P concentrations ranged from 0.005 to 0.012
mg/L; effluent ortho-P concentrations ranged from 0.005 to 0.013 mg/L. The reporting
limit/resolution for the ortho-P test method is 0.01 mg/L, therefore the influent and
effluent ortho-P concentrations were both at and near non-detect concentrations.
Field Testing 2008-2009
1. Filterra® completed field-testing at two sites at the Port of Tacoma. Continuous flow and
rainfall data collected during the 2008-2009 monitoring period indicated that 89 storm
events occurred. The monitoring obtained water quality data from 27 storm events. Not
all the sampled storms produced information that met TAPE criteria for storm and/or
water quality data.
2. During the testing at the Port of Tacoma, 98.96 to 99.89 percent of the annual influent
runoff volume passed through the POT1 and POT2 test systems respectively. Stormwater
runoff bypassed the POT1 test system during nine storm events and bypassed the POT2
test system during one storm event. Bypass volumes ranged from 0.13% to 15.3% of the
influent storm volume. Both test systems achieved the 91 percent water quality treatment-
goal over the 1-year monitoring period.
3. Consultants observed infiltration rates as high as 133 in/hr during the various storms.
Filterra® did not provide any paired data that identified percent removal of TSS, metals,
oil, or phosphorus at an instantaneous observed flow rate.
4. The maximum storm average hydraulic loading rate associated with water quality data is
<40 in/hr, with the majority of flow rates < 25 in/hr. The average instantaneous hydraulic
loading rate ranged from 8.6 to 53 inches per hour.
5. The field data showed a removal rate greater than 80% for TSS with an influent
concentration greater than 20 mg/l at an average instantaneous hydraulic loading rate up
to 53 in/hr (average influent concentration of 28.8 mg/l, average effluent concentration of
4.3 mg/l).
6. The field data showed a removal rate generally greater than 54% for dissolved zinc at an
average instantaneous hydraulic loading rate up to 60 in/hr and an average influent
concentration of 0.266 mg/l (average effluent concentration of 0.115 mg/l).
7. The field data showed a removal rate generally greater than 40% for dissolved copper at
an average instantaneous hydraulic loading rate up to 35 in/hr and an average influent
concentration of 0.0070 mg/l (average effluent concentration of 0.0036 mg/l).
8. The field data showed an average removal rate of 93% for total petroleum hydrocarbon
(TPH) at an average instantaneous hydraulic loading rate up to 53 in/hr and an average
influent concentration of 52 mg/l (average effluent concentration of 2.3 mg/l). The data
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also shows achievement of less than 15 mg/l TPH for grab samples. Filterra® provided
limited visible sheen data due to access limitations at the outlet monitoring location.
9. The field data showed low percentage removals of total phosphorus at all storm flows at
an average influent concentration of 0.189 mg/l (average effluent concentration of 0.171
mg/l). We may relate the relatively poor treatment performance of the Filterra® system at
this location to influent characteristics for total phosphorus that are unique to the Port of
Tacoma site. It appears that the Filterra® system will not meet the 50 percent removal
performance goal when you expect the majority of phosphorus in the runoff to be in the
dissolved form.
Laboratory Testing
1. Filterra® performed laboratory testing on a scaled down version of the Filterra® unit. The
lab data showed an average removal from 83-91% for TSS with influents ranging from
21 to 320 mg/L, 82-84% for total copper with influents ranging from 0.94 to 2.3 mg/L,
and 50-61% for orthophosphate with influents ranging from 2.46 to 14.37 mg/L.
2. Filterra® conducted permeability tests on the soil media.
3. Lab scale testing using Sil-Co-Sil 106 showed percent removals ranging from 70.1% to
95.5% with a median percent removal of 90.7%, for influent concentrations ranging from
8.3 to 260 mg/L. Filterra® ran these laboratory tests at an infiltration rate of 50 in/hr.
4. Supplemental lab testing conducted in September 2009 using Sil-Co-Sil 106 showed an
average percent removal of 90.6%. These laboratory tests were run at infiltration rates
ranging from 25 to 150 in/hr for influent concentrations ranging from 41.6 to 252.5 mg/l.
Regression analysis results indicate that the Filterra® system’s TSS removal performance
is independent of influent concentration in the concentration rage evaluated at hydraulic
loading rates of up to 150 in/hr.
Contact Information:
Applicant: Jeremiah Lehman
Contech Engineered Solutions, LLC.
11815 Glenn Widing Dr
Portland, OR 97220
(503) 258-3136
jlehman@conteches.com
Applicant’s Website: http://www.conteches.com
Ecology web link: http://www.ecy.wa.gov/programs/wq/stormwater/newtech/index.html
Ecology: Douglas C. Howie, P.E.
Department of Ecology
Water Quality Program
(360) 407-6444
douglas.howie@ecy.wa.gov
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
8
Date Revision
December 2009 GULD for Basic, Enhanced, and Oil granted, CULD for Phosphorus
September 2011 Extended CULD for Phosphorus Treatment
September 2012 Revised design storm discussion, added Shallow System.
January 2013 Revised format to match Ecology standards, changed Filterra contact
information
February 2013 Added FTIB-P system
March 2013 Added FTIB-C system
April 2013 Modified requirements for identifying appropriate size of unit
June 2013 Modified description of FTIB-C alternate configuration
March 2014 GULD awarded for Phosphorus Treatment. GULD updated for a
higher flow-rate for Basic Treatment.
June 2014 Revised sizing calculation methods
March 2015 Revised Contact Information
June 2015 CULD for Basic and Enhanced at 100 in/hr infiltration rate
November 2015 Removed information on CULD (created separate CULD document
for 100 in/hr infiltration rate)
June 2016 Revised text regarding Hydraulic conductivity value
November 2016 Revised Contech Contact information
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
KPFF Consulting EngineersCedar River ApartmentsKPFF Consulting EngineersJanuary, 2019West Conveyance RunASSUMPTIONS AND CONSTANTS cont.8 -in Pipe Wall Thickness =2.0in. (per WSDOT Hydraulics Manual Table 8-11.2 (English))12 -in Pipe Wall Thickness =2.0in. (per WSDOT Hydraulics Manual Table 8-11.2 (English))18 -in Pipe Wall Thickness =2.5in. (per WSDOT Hydraulics Manual Table 8-11.2 (English))24 -in Pipe Wall Thickness =3.0in. (per WSDOT Hydraulics Manual Table 8-11.2 (English))30 -in Pipe Wall Thickness =3.5in. (per WSDOT Hydraulics Manual Table 8-11.2 (English))Min Cover for Plain Conc. Pipe =2ft. (per WSDOT Hydraulics Manual Table 8-11.2 (English))Min Cover for Class IV Conc. Pipe =1.0ft. (per WSDOT Hydraulics Manual Table 8-11.2 (English))Min Cover for Class V Conc. Pipe =0.5ft. (per WSDOT Hydraulics Manual Table 8-11.2 (English))Project Pavement Thickness =0.33ft. LayoutPipe Capacity CalculationsStructure NumberInlet Rim ElevationOutlet Rim ElevationInlet Invert ElevationOutlet Invert ElevationPipe DiameterLength SlopeVelocity, VPipe Flow Capacity, Q Inlet CoverOutlet Cover(inches) (feet) (%) (ft/s) (cfs) (ft) (ft)1 18 19 20 21 22 23 24 27 28 29 30Storm Drainage Areas Include: Sub-basin 3A.1, Sub-basin 3A.2, Sub-basin 3D, off-site Sub-basin 3F.1, and off-site Sub-basin 3F.2Main Run0CB-11 50.3049.5046.7646.3312 in 85.28 ft0.50% 2.98 ft/s 2.34 cfs 2.4 ft 2.0 ftCB-10 49.5050.0046.3346.0512 in 55.96 ft0.50% 2.98 ft/s 2.34 cfs 2.0 ft 2.8 ftCB-9 50.0049.4346.0546.0112 in 8.24 ft0.50% 2.98 ft/s 2.34 cfs 2.8 ft 2.3 ftWQ#2 49.43 46.0143.4350.3643.4343.4012 in 5.83 ft0.50% 2.98 ft/s 2.34 cfs 4.8 ft 5.8 ftCB-8 50.3651.2143.4043.1912 in 41.64 ft0.50% 2.98 ft/s 2.34 cfs 5.8 ft 6.9 ftCB-7 51.2151.3443.1941.9012 in 257.39 ft0.50% 2.98 ft/s 2.34 cfs 6.9 ft 8.3 ftCB-6 51.3451.1041.9041.3112 in 98.88 ft0.60% 3.26 ft/s 2.56 cfs 8.3 ft 8.6 ftCB-5 51.1050.2041.3140.6912 in 103.04 ft0.60% 3.26 ft/s 2.56 cfs 8.6 ft 8.3 ftCB-4 50.2044.8040.6939.3212 in 229.46 ft0.60% 3.26 ft/s 2.56 cfs 8.3 ft 4.3 ftCB-3 44.8046.8039.3238.5712 in 124.36 ft0.60% 3.26 ft/s 2.56 cfs 4.3 ft 7.1 ftCB-2 46.8046.8038.5738.0612 in 84.23 ft0.60% 3.26 ft/s 2.56 cfs 7.1 ft 7.6 ftCB-1 46.8046.0038.0637.9312 in 22.51 ft0.60% 3.26 ft/s 2.56 cfs 7.6 ft 6.9 ftOutlet (west) 46.0037.9312 inStorm Drainage Areas Include: Sub-basin 3A.1, Sub-basin 3A.2, Sub-basin 3D, off-site Sub-basin 3F.1, and off-site Sub-basin 3F.2Filterra WQ Unit #1 Run0CB-8B 50.3050.3646.8346.3612 in 95.12 ft0.50% 2.98 ft/s 2.34 cfs 2.3 ft 2.8 ftCB-8A 50.3050.3646.3646.0112 in 69.01 ft0.50% 2.98 ft/s 2.34 cfs 2.8 ft 3.2 ftWQ#1 49.43 46.0143.4350.3643.4343.4012 in 6.97 ft0.50% 2.98 ft/s 2.34 cfs 4.8 ft 5.8 ftCB-8 50.3651.2143.4043.1912 in 41.64 ft0.50% 2.98 ft/s 2.34 cfs 5.8 ft 6.9 ftStorm Drainage Areas Include: Sub-basin 3A.1, Sub-basin 3A.2, Sub-basin 3D, off-site Sub-basin 3F.1, and off-site Sub-basin 3F.2SW Courtyard Run0CB-1A 51.0046.8038.4438.0612 in 62.02 ft0.60% 3.26 ft/s 2.56 cfs 11.4 ft 7.6 ftCB-1 46.8046.0038.0637.9312 in 22.51 ft0.60% 3.26 ft/s 2.56 cfs 7.6 ft 6.9 ftASSUMPTIONS AND CONSTANTSManning's n =0.014(per CORSWDM Table 4.2.1D for Corrugated Polyethylene Pipe (CPE) - Uniform Flow)Conveyance Design(west).exhibit.xlsm | 25yr UF1 of 11/10/2019 | 12:41 PMDocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
KPFF Consulting EngineersCedar River ApartmentsKPFF Consulting EngineersJanuary, 2019East Conveyance RunASSUMPTIONS AND CONSTANTS cont.8 -in Pipe Wall Thickness = 2.0 in. (per WSDOT Hydraulics Manual Table 8-11.2 (English))12 -in Pipe Wall Thickness = 2.0 in. (per WSDOT Hydraulics Manual Table 8-11.2 (English))15 -in Pipe Wall Thickness = 2.5 in.18 -in Pipe Wall Thickness = 2.5 in. (per WSDOT Hydraulics Manual Table 8-11.2 (English))24 -in Pipe Wall Thickness = 3.0 in. (per WSDOT Hydraulics Manual Table 8-11.2 (English))30 -in Pipe Wall Thickness = 3.5 in. (per WSDOT Hydraulics Manual Table 8-11.2 (English))Min Cover for CPE Pipe = 2 ft. (per WSDOT Hydraulics Manual Table 8-11.2 (English))Min Cover for Class IV Conc. Pipe = ft. (per WSDOT Hydraulics Manual Table 8-11.2 (English))Min Cover for Class V Conc. Pipe = ft. (per WSDOT Hydraulics Manual Table 8-11.2 (English))Project Pavement Thickness = 0.33 ft.LayoutPipe Capacity CalculationsStructure NumberInlet Rim ElevationOutlet Rim ElevationInlet Invert ElevationOutlet Invert ElevationPipe DiameterLength SlopeVelocity, VPipe Flow Capacity, Q Inlet CoverOutlet Cover(inches) (feet) (%) (ft/s) (cfs) (ft) (ft)1 18 19 20 21 22 23 24 27 28 29 30Storm Drainage Areas Include: Sub-basin 3B, Sub-basin 3A.3, Sub-basin 3C, and off-site Sub-basin 3F.3Main Run0CB-22 50.3050.3047.1346.7212 in 82.0 ft0.50% 2.98 ft/s 2.34 cfs 2.0 ft 2.4 ftCB-21 50.3052.5046.7246.3212 in 79.8 ft0.50% 2.98 ft/s 2.34 cfs 2.4 ft 5.0 ftCB-20 52.5051.5046.3246.1212 in 41.2 ft0.50% 2.98 ft/s 2.34 cfs 5.0 ft 4.2 ftCB-19 51.5049.3846.1245.9712 in 30.6 ft0.50% 2.98 ft/s 2.34 cfs 4.2 ft 2.3 ftWQ#3 49.38 45.9743.3852.5043.3842.9612 in 85.2 ft0.50% 2.98 ft/s 2.34 cfs 4.8 ft 8.4 ftCB-17 52.5050.9042.9642.4512 in 101.0 ft0.50% 2.98 ft/s 2.34 cfs 8.4 ft 7.3 ftCB-16 50.9053.0042.4541.8112 in 127.9 ft0.50% 2.98 ft/s 2.34 cfs 7.3 ft 10.0 ftCB-15 53.0051.0041.8141.4212 in 77.2 ft0.50% 2.98 ft/s 2.34 cfs 10.0 ft 8.4 ftCB-14 51.0046.9041.4240.1012 in 265.3 ft0.50% 2.98 ft/s 2.34 cfs 8.4 ft 5.6 ftCB-13 46.9046.0040.1039.9512 in 29.7 ft0.50% 2.98 ft/s 2.34 cfs 5.6 ft 4.9 ftCB-12 46.0042.0039.9538.4812 in 294.5 ft0.50% 2.98 ft/s 2.34 cfs 4.9 ft 2.4 ftOutfall (east) 42.0038.4812 inStorm Drainage Areas Include: Sub-basin 3B, Sub-basin 3A.3, Sub-basin 3C, and off-site Sub-basin 3F.3Bypass Run0CB-18 48.3052.5043.7442.9612 in 157.5 ft0.50% 2.98 ft/s 2.34 cfs 3.4 ft 8.4 ftCB-17 52.5050.9042.9642.4512 in 101.0 ft0.50% 2.98 ft/s 2.34 cfs 8.4 ft 7.3 ftASSUMPTIONS AND CONSTANTSManning's n =0.014(per CORSWDM Table 4.2.1D for Corrugated Polyethylene Pipe (CPE) - Uniform Flow)Conveyance Design (east).exhibit.xlsm | 25yr UF1 of 11/11/2019 | 10:21 AMDocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WWHM2012
PROJECT REPORT
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ1 1/11/2019 10:25:52 AM Page 2
General Model Information
Project Name:WQ1
Site Name:Cedar River Apartments
Site Address:1915 Maple Valley Highway
City:Renton, WA 98057
Report Date:1/11/2019
Gage:Seatac
Data Start:1948/10/01
Data End:2009/09/30
Timestep:15 Minute
Precip Scale:1.000
Version Date:2018/03/02
Version:4.2.14
POC Thresholds
Low Flow Threshold for POC1:50 Percent of the 2 Year
High Flow Threshold for POC1:50 Year
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ1 1/11/2019 10:25:52 AM Page 4
Mitigated Land Use
Sub-basin 3A.1
Bypass:No
GroundWater:No
Pervious Land Use acre
C, Lawn, Mod 0.25
Pervious Total 0.25
Impervious Land Use acre
PARKING FLAT 0.83
Impervious Total 0.83
Basin Total 1.08
Element Flows To:
Surface Interflow Groundwater
Filterra WQ Unit #1 Filterra WQ Unit #1
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ1 1/11/2019 10:25:52 AM Page 6
Mitigated Routing
Filterra WQ Unit #1
Bottom Length:11.50 ft.
Bottom Width:8.00 ft.
Depth:0.75 ft.
Side slope 1:0 To 1
Side slope 2:0 To 1
Side slope 3:0 To 1
Side slope 4:0 To 1
Filtration On
Hydraulic conductivity:24.82
Depth of filter medium:1.8
Total Volume Infiltrated (ac-ft.):135.035
Total Volume Through Riser (ac-ft.):12.771
Total Volume Through Facility (ac-ft.):147.807
Percent Infiltrated:91.36
Total Precip Applied to Facility:0
Total Evap From Facility:0
Discharge Structure
Riser Height:0.7 ft.
Riser Diameter:100 in.
Element Flows To:
Outlet 1 Outlet 2
Sand Filter Hydraulic Table
Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs)
0.0000 0.002112 0.000000 0.000 0.000
0.0083 0.002112 0.000018 0.000 0.053
0.0167 0.002112 0.000035 0.000 0.053
0.0250 0.002112 0.000053 0.000 0.053
0.0333 0.002112 0.000070 0.000 0.053
0.0417 0.002112 0.000088 0.000 0.054
0.0500 0.002112 0.000106 0.000 0.054
0.0583 0.002112 0.000123 0.000 0.054
0.0667 0.002112 0.000141 0.000 0.054
0.0750 0.002112 0.000158 0.000 0.055
0.0833 0.002112 0.000176 0.000 0.055
0.0917 0.002112 0.000194 0.000 0.055
0.1000 0.002112 0.000211 0.000 0.055
0.1083 0.002112 0.000229 0.000 0.056
0.1167 0.002112 0.000246 0.000 0.056
0.1250 0.002112 0.000264 0.000 0.056
0.1333 0.002112 0.000282 0.000 0.056
0.1417 0.002112 0.000299 0.000 0.057
0.1500 0.002112 0.000317 0.000 0.057
0.1583 0.002112 0.000334 0.000 0.057
0.1667 0.002112 0.000352 0.000 0.057
0.1750 0.002112 0.000370 0.000 0.058
0.1833 0.002112 0.000387 0.000 0.058
0.1917 0.002112 0.000405 0.000 0.058
0.2000 0.002112 0.000422 0.000 0.058
0.2083 0.002112 0.000440 0.000 0.059
0.2167 0.002112 0.000458 0.000 0.059
0.2250 0.002112 0.000475 0.000 0.059
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ1 1/11/2019 10:25:52 AM Page 7
0.2333 0.002112 0.000493 0.000 0.059
0.2417 0.002112 0.000510 0.000 0.060
0.2500 0.002112 0.000528 0.000 0.060
0.2583 0.002112 0.000546 0.000 0.060
0.2667 0.002112 0.000563 0.000 0.060
0.2750 0.002112 0.000581 0.000 0.060
0.2833 0.002112 0.000598 0.000 0.061
0.2917 0.002112 0.000616 0.000 0.061
0.3000 0.002112 0.000634 0.000 0.061
0.3083 0.002112 0.000651 0.000 0.061
0.3167 0.002112 0.000669 0.000 0.062
0.3250 0.002112 0.000686 0.000 0.062
0.3333 0.002112 0.000704 0.000 0.062
0.3417 0.002112 0.000722 0.000 0.062
0.3500 0.002112 0.000739 0.000 0.063
0.3583 0.002112 0.000757 0.000 0.063
0.3667 0.002112 0.000774 0.000 0.063
0.3750 0.002112 0.000792 0.000 0.063
0.3833 0.002112 0.000810 0.000 0.064
0.3917 0.002112 0.000827 0.000 0.064
0.4000 0.002112 0.000845 0.000 0.064
0.4083 0.002112 0.000862 0.000 0.064
0.4167 0.002112 0.000880 0.000 0.065
0.4250 0.002112 0.000898 0.000 0.065
0.4333 0.002112 0.000915 0.000 0.065
0.4417 0.002112 0.000933 0.000 0.065
0.4500 0.002112 0.000950 0.000 0.066
0.4583 0.002112 0.000968 0.000 0.066
0.4667 0.002112 0.000986 0.000 0.066
0.4750 0.002112 0.001003 0.000 0.066
0.4833 0.002112 0.001021 0.000 0.067
0.4917 0.002112 0.001038 0.000 0.067
0.5000 0.002112 0.001056 0.000 0.067
0.5083 0.002112 0.001074 0.000 0.067
0.5167 0.002112 0.001091 0.000 0.068
0.5250 0.002112 0.001109 0.000 0.068
0.5333 0.002112 0.001126 0.000 0.068
0.5417 0.002112 0.001144 0.000 0.068
0.5500 0.002112 0.001162 0.000 0.069
0.5583 0.002112 0.001179 0.000 0.069
0.5667 0.002112 0.001197 0.000 0.069
0.5750 0.002112 0.001214 0.000 0.069
0.5833 0.002112 0.001232 0.000 0.070
0.5917 0.002112 0.001250 0.000 0.070
0.6000 0.002112 0.001267 0.000 0.070
0.6083 0.002112 0.001285 0.000 0.070
0.6167 0.002112 0.001302 0.000 0.071
0.6250 0.002112 0.001320 0.000 0.071
0.6333 0.002112 0.001338 0.000 0.071
0.6417 0.002112 0.001355 0.000 0.071
0.6500 0.002112 0.001373 0.000 0.071
0.6583 0.002112 0.001390 0.000 0.072
0.6667 0.002112 0.001408 0.000 0.072
0.6750 0.002112 0.001426 0.000 0.072
0.6833 0.002112 0.001443 0.000 0.072
0.6917 0.002112 0.001461 0.000 0.073
0.7000 0.002112 0.001478 0.000 0.073
0.7083 0.002112 0.001496 0.067 0.073
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ1 1/11/2019 10:25:52 AM Page 8
0.7167 0.002112 0.001514 0.190 0.073
0.7250 0.002112 0.001531 0.349 0.074
0.7333 0.002112 0.001549 0.538 0.074
0.7417 0.002112 0.001566 0.752 0.074
0.7500 0.002112 0.001584 0.989 0.074
0.7583 0.002112 0.001602 1.246 0.075
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ1 1/11/2019 10:26:36 AM Page 19
Mitigated Schematic
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ1 1/11/2019 10:26:38 AM Page 32
Disclaimer
Legal Notice
This program and accompanying documentation are provided 'as-is' without warranty of any kind. The
entire risk regarding the performance and results of this program is assumed by End User. Clear
Creek Solutions Inc. and the governmental licensee or sublicensees disclaim all warranties, either
expressed or implied, including but not limited to implied warranties of program and accompanying
documentation. In no event shall Clear Creek Solutions Inc. be liable for any damages whatsoever
(including without limitation to damages for loss of business profits, loss of business information,
business interruption, and the like) arising out of the use of, or inability to use this program even
if Clear Creek Solutions Inc. or their authorized representatives have been advised of the
possibility of such damages. Software Copyright © by : Clear Creek Solutions, Inc. 2005-2019; All
Rights Reserved.
Clear Creek Solutions, Inc.
6200 Capitol Blvd. Ste F
Olympia, WA. 98501
Toll Free 1(866)943-0304
Local (360)943-0304
www.clearcreeksolutions.com
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WWHM2012
PROJECT REPORT
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/8/2019 12:00:52 PM Page 2
General Model Information
Project Name:WQ2
Site Name:Cedar River Apartments
Site Address:1915 Maple Valley Highway
City:Renton, WA 98057
Report Date:1/8/2019
Gage:Seatac
Data Start:1948/10/01
Data End:2009/09/30
Timestep:15 Minute
Precip Scale:1.000
Version Date:2018/03/02
Version:4.2.14
POC Thresholds
Low Flow Threshold for POC1:50 Percent of the 2 Year
High Flow Threshold for POC1:50 Year
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/8/2019 12:00:52 PM Page 4
Mitigated Land Use
Basin 1
Bypass:No
GroundWater:No
Pervious Land Use acre
C, Lawn, Mod 0.28
Pervious Total 0.28
Impervious Land Use acre
PARKING FLAT 0.37
Impervious Total 0.37
Basin Total 0.65
Element Flows To:
Surface Interflow Groundwater
Filterra Unit Filterra Unit
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/8/2019 12:00:52 PM Page 6
Mitigated Routing
Filterra Unit
Bottom Length:7.50 ft.
Bottom Width:6.00 ft.
Depth:0.75 ft.
Side slope 1:0 To 1
Side slope 2:0 To 1
Side slope 3:0 To 1
Side slope 4:0 To 1
Filtration On
Hydraulic conductivity:24.82
Depth of filter medium:1.8
Total Volume Infiltrated (ac-ft.):72.219
Total Volume Through Riser (ac-ft.):5.708
Total Volume Through Facility (ac-ft.):77.927
Percent Infiltrated:92.68
Total Precip Applied to Facility:0
Total Evap From Facility:0
Discharge Structure
Riser Height:0.7 ft.
Riser Diameter:100 in.
Element Flows To:
Outlet 1 Outlet 2
Sand Filter Hydraulic Table
Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs)
0.0000 0.001033 0.000000 0.000 0.000
0.0083 0.001033 0.000009 0.000 0.026
0.0167 0.001033 0.000017 0.000 0.026
0.0250 0.001033 0.000026 0.000 0.026
0.0333 0.001033 0.000034 0.000 0.026
0.0417 0.001033 0.000043 0.000 0.026
0.0500 0.001033 0.000052 0.000 0.026
0.0583 0.001033 0.000060 0.000 0.026
0.0667 0.001033 0.000069 0.000 0.026
0.0750 0.001033 0.000077 0.000 0.026
0.0833 0.001033 0.000086 0.000 0.027
0.0917 0.001033 0.000095 0.000 0.027
0.1000 0.001033 0.000103 0.000 0.027
0.1083 0.001033 0.000112 0.000 0.027
0.1167 0.001033 0.000121 0.000 0.027
0.1250 0.001033 0.000129 0.000 0.027
0.1333 0.001033 0.000138 0.000 0.027
0.1417 0.001033 0.000146 0.000 0.027
0.1500 0.001033 0.000155 0.000 0.028
0.1583 0.001033 0.000164 0.000 0.028
0.1667 0.001033 0.000172 0.000 0.028
0.1750 0.001033 0.000181 0.000 0.028
0.1833 0.001033 0.000189 0.000 0.028
0.1917 0.001033 0.000198 0.000 0.028
0.2000 0.001033 0.000207 0.000 0.028
0.2083 0.001033 0.000215 0.000 0.028
0.2167 0.001033 0.000224 0.000 0.029
0.2250 0.001033 0.000232 0.000 0.029
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/8/2019 12:00:52 PM Page 7
0.2333 0.001033 0.000241 0.000 0.029
0.2417 0.001033 0.000250 0.000 0.029
0.2500 0.001033 0.000258 0.000 0.029
0.2583 0.001033 0.000267 0.000 0.029
0.2667 0.001033 0.000275 0.000 0.029
0.2750 0.001033 0.000284 0.000 0.029
0.2833 0.001033 0.000293 0.000 0.029
0.2917 0.001033 0.000301 0.000 0.030
0.3000 0.001033 0.000310 0.000 0.030
0.3083 0.001033 0.000319 0.000 0.030
0.3167 0.001033 0.000327 0.000 0.030
0.3250 0.001033 0.000336 0.000 0.030
0.3333 0.001033 0.000344 0.000 0.030
0.3417 0.001033 0.000353 0.000 0.030
0.3500 0.001033 0.000362 0.000 0.030
0.3583 0.001033 0.000370 0.000 0.031
0.3667 0.001033 0.000379 0.000 0.031
0.3750 0.001033 0.000387 0.000 0.031
0.3833 0.001033 0.000396 0.000 0.031
0.3917 0.001033 0.000405 0.000 0.031
0.4000 0.001033 0.000413 0.000 0.031
0.4083 0.001033 0.000422 0.000 0.031
0.4167 0.001033 0.000430 0.000 0.031
0.4250 0.001033 0.000439 0.000 0.032
0.4333 0.001033 0.000448 0.000 0.032
0.4417 0.001033 0.000456 0.000 0.032
0.4500 0.001033 0.000465 0.000 0.032
0.4583 0.001033 0.000473 0.000 0.032
0.4667 0.001033 0.000482 0.000 0.032
0.4750 0.001033 0.000491 0.000 0.032
0.4833 0.001033 0.000499 0.000 0.032
0.4917 0.001033 0.000508 0.000 0.032
0.5000 0.001033 0.000517 0.000 0.033
0.5083 0.001033 0.000525 0.000 0.033
0.5167 0.001033 0.000534 0.000 0.033
0.5250 0.001033 0.000542 0.000 0.033
0.5333 0.001033 0.000551 0.000 0.033
0.5417 0.001033 0.000560 0.000 0.033
0.5500 0.001033 0.000568 0.000 0.033
0.5583 0.001033 0.000577 0.000 0.033
0.5667 0.001033 0.000585 0.000 0.034
0.5750 0.001033 0.000594 0.000 0.034
0.5833 0.001033 0.000603 0.000 0.034
0.5917 0.001033 0.000611 0.000 0.034
0.6000 0.001033 0.000620 0.000 0.034
0.6083 0.001033 0.000628 0.000 0.034
0.6167 0.001033 0.000637 0.000 0.034
0.6250 0.001033 0.000646 0.000 0.034
0.6333 0.001033 0.000654 0.000 0.035
0.6417 0.001033 0.000663 0.000 0.035
0.6500 0.001033 0.000671 0.000 0.035
0.6583 0.001033 0.000680 0.000 0.035
0.6667 0.001033 0.000689 0.000 0.035
0.6750 0.001033 0.000697 0.000 0.035
0.6833 0.001033 0.000706 0.000 0.035
0.6917 0.001033 0.000715 0.000 0.035
0.7000 0.001033 0.000723 0.000 0.035
0.7083 0.001033 0.000732 0.067 0.036
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/8/2019 12:00:52 PM Page 8
0.7167 0.001033 0.000740 0.190 0.036
0.7250 0.001033 0.000749 0.349 0.036
0.7333 0.001033 0.000758 0.538 0.036
0.7417 0.001033 0.000766 0.752 0.036
0.7500 0.001033 0.000775 0.989 0.036
0.7583 0.001033 0.000783 1.246 0.036
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/8/2019 12:01:39 PM Page 19
Mitigated Schematic
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WWHM2012
PROJECT REPORT
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/11/2019 10:33:14 AM Page 2
General Model Information
Project Name:WQ2
Site Name:Cedar River Apartments
Site Address:1915 Maple Valley Highway
City:Renton, WA 98057
Report Date:1/11/2019
Gage:Seatac
Data Start:1948/10/01
Data End:2009/09/30
Timestep:15 Minute
Precip Scale:1.000
Version Date:2018/03/02
Version:4.2.14
POC Thresholds
Low Flow Threshold for POC1:50 Percent of the 2 Year
High Flow Threshold for POC1:50 Year
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/11/2019 10:33:14 AM Page 4
Mitigated Land Use
Sub-basin 3A.2
Bypass:No
GroundWater:No
Pervious Land Use acre
C, Lawn, Mod 0.28
Pervious Total 0.28
Impervious Land Use acre
PARKING FLAT 0.39
Impervious Total 0.39
Basin Total 0.67
Element Flows To:
Surface Interflow Groundwater
Filterra WQ Unit #2 Filterra WQ Unit #2
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/11/2019 10:33:14 AM Page 6
Mitigated Routing
Filterra WQ Unit #2
Bottom Length:7.50 ft.
Bottom Width:6.00 ft.
Depth:0.75 ft.
Side slope 1:0 To 1
Side slope 2:0 To 1
Side slope 3:0 To 1
Side slope 4:0 To 1
Filtration On
Hydraulic conductivity:24.82
Depth of filter medium:1.8
Total Volume Infiltrated (ac-ft.):74.506
Total Volume Through Riser (ac-ft.):6.557
Total Volume Through Facility (ac-ft.):81.063
Percent Infiltrated:91.91
Total Precip Applied to Facility:0
Total Evap From Facility:0
Discharge Structure
Riser Height:0.7 ft.
Riser Diameter:100 in.
Element Flows To:
Outlet 1 Outlet 2
Sand Filter Hydraulic Table
Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs)
0.0000 0.001033 0.000000 0.000 0.000
0.0083 0.001033 0.000009 0.000 0.026
0.0167 0.001033 0.000017 0.000 0.026
0.0250 0.001033 0.000026 0.000 0.026
0.0333 0.001033 0.000034 0.000 0.026
0.0417 0.001033 0.000043 0.000 0.026
0.0500 0.001033 0.000052 0.000 0.026
0.0583 0.001033 0.000060 0.000 0.026
0.0667 0.001033 0.000069 0.000 0.026
0.0750 0.001033 0.000077 0.000 0.026
0.0833 0.001033 0.000086 0.000 0.027
0.0917 0.001033 0.000095 0.000 0.027
0.1000 0.001033 0.000103 0.000 0.027
0.1083 0.001033 0.000112 0.000 0.027
0.1167 0.001033 0.000121 0.000 0.027
0.1250 0.001033 0.000129 0.000 0.027
0.1333 0.001033 0.000138 0.000 0.027
0.1417 0.001033 0.000146 0.000 0.027
0.1500 0.001033 0.000155 0.000 0.028
0.1583 0.001033 0.000164 0.000 0.028
0.1667 0.001033 0.000172 0.000 0.028
0.1750 0.001033 0.000181 0.000 0.028
0.1833 0.001033 0.000189 0.000 0.028
0.1917 0.001033 0.000198 0.000 0.028
0.2000 0.001033 0.000207 0.000 0.028
0.2083 0.001033 0.000215 0.000 0.028
0.2167 0.001033 0.000224 0.000 0.029
0.2250 0.001033 0.000232 0.000 0.029
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/11/2019 10:33:14 AM Page 7
0.2333 0.001033 0.000241 0.000 0.029
0.2417 0.001033 0.000250 0.000 0.029
0.2500 0.001033 0.000258 0.000 0.029
0.2583 0.001033 0.000267 0.000 0.029
0.2667 0.001033 0.000275 0.000 0.029
0.2750 0.001033 0.000284 0.000 0.029
0.2833 0.001033 0.000293 0.000 0.029
0.2917 0.001033 0.000301 0.000 0.030
0.3000 0.001033 0.000310 0.000 0.030
0.3083 0.001033 0.000319 0.000 0.030
0.3167 0.001033 0.000327 0.000 0.030
0.3250 0.001033 0.000336 0.000 0.030
0.3333 0.001033 0.000344 0.000 0.030
0.3417 0.001033 0.000353 0.000 0.030
0.3500 0.001033 0.000362 0.000 0.030
0.3583 0.001033 0.000370 0.000 0.031
0.3667 0.001033 0.000379 0.000 0.031
0.3750 0.001033 0.000387 0.000 0.031
0.3833 0.001033 0.000396 0.000 0.031
0.3917 0.001033 0.000405 0.000 0.031
0.4000 0.001033 0.000413 0.000 0.031
0.4083 0.001033 0.000422 0.000 0.031
0.4167 0.001033 0.000430 0.000 0.031
0.4250 0.001033 0.000439 0.000 0.032
0.4333 0.001033 0.000448 0.000 0.032
0.4417 0.001033 0.000456 0.000 0.032
0.4500 0.001033 0.000465 0.000 0.032
0.4583 0.001033 0.000473 0.000 0.032
0.4667 0.001033 0.000482 0.000 0.032
0.4750 0.001033 0.000491 0.000 0.032
0.4833 0.001033 0.000499 0.000 0.032
0.4917 0.001033 0.000508 0.000 0.032
0.5000 0.001033 0.000517 0.000 0.033
0.5083 0.001033 0.000525 0.000 0.033
0.5167 0.001033 0.000534 0.000 0.033
0.5250 0.001033 0.000542 0.000 0.033
0.5333 0.001033 0.000551 0.000 0.033
0.5417 0.001033 0.000560 0.000 0.033
0.5500 0.001033 0.000568 0.000 0.033
0.5583 0.001033 0.000577 0.000 0.033
0.5667 0.001033 0.000585 0.000 0.034
0.5750 0.001033 0.000594 0.000 0.034
0.5833 0.001033 0.000603 0.000 0.034
0.5917 0.001033 0.000611 0.000 0.034
0.6000 0.001033 0.000620 0.000 0.034
0.6083 0.001033 0.000628 0.000 0.034
0.6167 0.001033 0.000637 0.000 0.034
0.6250 0.001033 0.000646 0.000 0.034
0.6333 0.001033 0.000654 0.000 0.035
0.6417 0.001033 0.000663 0.000 0.035
0.6500 0.001033 0.000671 0.000 0.035
0.6583 0.001033 0.000680 0.000 0.035
0.6667 0.001033 0.000689 0.000 0.035
0.6750 0.001033 0.000697 0.000 0.035
0.6833 0.001033 0.000706 0.000 0.035
0.6917 0.001033 0.000715 0.000 0.035
0.7000 0.001033 0.000723 0.000 0.035
0.7083 0.001033 0.000732 0.067 0.036
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/11/2019 10:33:14 AM Page 8
0.7167 0.001033 0.000740 0.190 0.036
0.7250 0.001033 0.000749 0.349 0.036
0.7333 0.001033 0.000758 0.538 0.036
0.7417 0.001033 0.000766 0.752 0.036
0.7500 0.001033 0.000775 0.989 0.036
0.7583 0.001033 0.000783 1.246 0.036
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/11/2019 10:33:58 AM Page 19
Mitigated Schematic
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ2 1/11/2019 10:34:00 AM Page 29
Disclaimer
Legal Notice
This program and accompanying documentation are provided 'as-is' without warranty of any kind. The
entire risk regarding the performance and results of this program is assumed by End User. Clear
Creek Solutions Inc. and the governmental licensee or sublicensees disclaim all warranties, either
expressed or implied, including but not limited to implied warranties of program and accompanying
documentation. In no event shall Clear Creek Solutions Inc. be liable for any damages whatsoever
(including without limitation to damages for loss of business profits, loss of business information,
business interruption, and the like) arising out of the use of, or inability to use this program even
if Clear Creek Solutions Inc. or their authorized representatives have been advised of the
possibility of such damages. Software Copyright © by : Clear Creek Solutions, Inc. 2005-2019; All
Rights Reserved.
Clear Creek Solutions, Inc.
6200 Capitol Blvd. Ste F
Olympia, WA. 98501
Toll Free 1(866)943-0304
Local (360)943-0304
www.clearcreeksolutions.com
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WWHM2012
PROJECT REPORT
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ3 1/11/2019 10:38:59 AM Page 2
General Model Information
Project Name:WQ3
Site Name:Cedar River Apartments
Site Address:1915 Maple Valley Highway
City:Renton, WA 98057
Report Date:1/11/2019
Gage:Seatac
Data Start:1948/10/01
Data End:2009/09/30
Timestep:15 Minute
Precip Scale:1.000
Version Date:2018/03/02
Version:4.2.14
POC Thresholds
Low Flow Threshold for POC1:50 Percent of the 2 Year
High Flow Threshold for POC1:50 Year
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ3 1/11/2019 10:38:59 AM Page 4
Mitigated Land Use
Sub-basin 3A.3
Bypass:No
GroundWater:No
Pervious Land Use acre
C, Lawn, Mod 0.01
Pervious Total 0.01
Impervious Land Use acre
PARKING FLAT 0.77
Impervious Total 0.77
Basin Total 0.78
Element Flows To:
Surface Interflow Groundwater
Filterra WQ Unit #3 Filterra WQ Unit #3
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ3 1/11/2019 10:38:59 AM Page 6
Mitigated Routing
Filterra WQ Unit #3
Bottom Length:11.50 ft.
Bottom Width:8.00 ft.
Depth:0.75 ft.
Side slope 1:0 To 1
Side slope 2:0 To 1
Side slope 3:0 To 1
Side slope 4:0 To 1
Filtration On
Hydraulic conductivity:24.82
Depth of filter medium:1.8
Total Volume Infiltrated (ac-ft.):111.328
Total Volume Through Riser (ac-ft.):9.048
Total Volume Through Facility (ac-ft.):120.376
Percent Infiltrated:92.48
Total Precip Applied to Facility:0
Total Evap From Facility:0
Discharge Structure
Riser Height:0.7 ft.
Riser Diameter:100 in.
Element Flows To:
Outlet 1 Outlet 2
Sand Filter Hydraulic Table
Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs)
0.0000 0.002112 0.000000 0.000 0.000
0.0083 0.002112 0.000018 0.000 0.053
0.0167 0.002112 0.000035 0.000 0.053
0.0250 0.002112 0.000053 0.000 0.053
0.0333 0.002112 0.000070 0.000 0.053
0.0417 0.002112 0.000088 0.000 0.054
0.0500 0.002112 0.000106 0.000 0.054
0.0583 0.002112 0.000123 0.000 0.054
0.0667 0.002112 0.000141 0.000 0.054
0.0750 0.002112 0.000158 0.000 0.055
0.0833 0.002112 0.000176 0.000 0.055
0.0917 0.002112 0.000194 0.000 0.055
0.1000 0.002112 0.000211 0.000 0.055
0.1083 0.002112 0.000229 0.000 0.056
0.1167 0.002112 0.000246 0.000 0.056
0.1250 0.002112 0.000264 0.000 0.056
0.1333 0.002112 0.000282 0.000 0.056
0.1417 0.002112 0.000299 0.000 0.057
0.1500 0.002112 0.000317 0.000 0.057
0.1583 0.002112 0.000334 0.000 0.057
0.1667 0.002112 0.000352 0.000 0.057
0.1750 0.002112 0.000370 0.000 0.058
0.1833 0.002112 0.000387 0.000 0.058
0.1917 0.002112 0.000405 0.000 0.058
0.2000 0.002112 0.000422 0.000 0.058
0.2083 0.002112 0.000440 0.000 0.059
0.2167 0.002112 0.000458 0.000 0.059
0.2250 0.002112 0.000475 0.000 0.059
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ3 1/11/2019 10:38:59 AM Page 7
0.2333 0.002112 0.000493 0.000 0.059
0.2417 0.002112 0.000510 0.000 0.060
0.2500 0.002112 0.000528 0.000 0.060
0.2583 0.002112 0.000546 0.000 0.060
0.2667 0.002112 0.000563 0.000 0.060
0.2750 0.002112 0.000581 0.000 0.060
0.2833 0.002112 0.000598 0.000 0.061
0.2917 0.002112 0.000616 0.000 0.061
0.3000 0.002112 0.000634 0.000 0.061
0.3083 0.002112 0.000651 0.000 0.061
0.3167 0.002112 0.000669 0.000 0.062
0.3250 0.002112 0.000686 0.000 0.062
0.3333 0.002112 0.000704 0.000 0.062
0.3417 0.002112 0.000722 0.000 0.062
0.3500 0.002112 0.000739 0.000 0.063
0.3583 0.002112 0.000757 0.000 0.063
0.3667 0.002112 0.000774 0.000 0.063
0.3750 0.002112 0.000792 0.000 0.063
0.3833 0.002112 0.000810 0.000 0.064
0.3917 0.002112 0.000827 0.000 0.064
0.4000 0.002112 0.000845 0.000 0.064
0.4083 0.002112 0.000862 0.000 0.064
0.4167 0.002112 0.000880 0.000 0.065
0.4250 0.002112 0.000898 0.000 0.065
0.4333 0.002112 0.000915 0.000 0.065
0.4417 0.002112 0.000933 0.000 0.065
0.4500 0.002112 0.000950 0.000 0.066
0.4583 0.002112 0.000968 0.000 0.066
0.4667 0.002112 0.000986 0.000 0.066
0.4750 0.002112 0.001003 0.000 0.066
0.4833 0.002112 0.001021 0.000 0.067
0.4917 0.002112 0.001038 0.000 0.067
0.5000 0.002112 0.001056 0.000 0.067
0.5083 0.002112 0.001074 0.000 0.067
0.5167 0.002112 0.001091 0.000 0.068
0.5250 0.002112 0.001109 0.000 0.068
0.5333 0.002112 0.001126 0.000 0.068
0.5417 0.002112 0.001144 0.000 0.068
0.5500 0.002112 0.001162 0.000 0.069
0.5583 0.002112 0.001179 0.000 0.069
0.5667 0.002112 0.001197 0.000 0.069
0.5750 0.002112 0.001214 0.000 0.069
0.5833 0.002112 0.001232 0.000 0.070
0.5917 0.002112 0.001250 0.000 0.070
0.6000 0.002112 0.001267 0.000 0.070
0.6083 0.002112 0.001285 0.000 0.070
0.6167 0.002112 0.001302 0.000 0.071
0.6250 0.002112 0.001320 0.000 0.071
0.6333 0.002112 0.001338 0.000 0.071
0.6417 0.002112 0.001355 0.000 0.071
0.6500 0.002112 0.001373 0.000 0.071
0.6583 0.002112 0.001390 0.000 0.072
0.6667 0.002112 0.001408 0.000 0.072
0.6750 0.002112 0.001426 0.000 0.072
0.6833 0.002112 0.001443 0.000 0.072
0.6917 0.002112 0.001461 0.000 0.073
0.7000 0.002112 0.001478 0.000 0.073
0.7083 0.002112 0.001496 0.067 0.073
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ3 1/11/2019 10:38:59 AM Page 8
0.7167 0.002112 0.001514 0.190 0.073
0.7250 0.002112 0.001531 0.349 0.074
0.7333 0.002112 0.001549 0.538 0.074
0.7417 0.002112 0.001566 0.752 0.074
0.7500 0.002112 0.001584 0.989 0.074
0.7583 0.002112 0.001602 1.246 0.075
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ3 1/11/2019 10:39:33 AM Page 19
Mitigated Schematic
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
WQ3 1/11/2019 10:39:35 AM Page 29
Disclaimer
Legal Notice
This program and accompanying documentation are provided 'as-is' without warranty of any kind. The
entire risk regarding the performance and results of this program is assumed by End User. Clear
Creek Solutions Inc. and the governmental licensee or sublicensees disclaim all warranties, either
expressed or implied, including but not limited to implied warranties of program and accompanying
documentation. In no event shall Clear Creek Solutions Inc. be liable for any damages whatsoever
(including without limitation to damages for loss of business profits, loss of business information,
business interruption, and the like) arising out of the use of, or inability to use this program even
if Clear Creek Solutions Inc. or their authorized representatives have been advised of the
possibility of such damages. Software Copyright © by : Clear Creek Solutions, Inc. 2005-2019; All
Rights Reserved.
Clear Creek Solutions, Inc.
6200 Capitol Blvd. Ste F
Olympia, WA. 98501
Toll Free 1(866)943-0304
Local (360)943-0304
www.clearcreeksolutions.com
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
—————————————————————————————————
MGS FLOOD
PROJECT REPORT
Program Version: MGSFlood 4.46
Program License Number: 200410007
Project Simulation Performed on: 01/08/2019 11:13 AM
Report Generation Date: 01/08/2019 11:21 AM
—————————————————————————————————
Input File Name: Sub-basin 3A.1.fld
Project Name: SRM Renton
Analysis Title:
Comments:
———————————————— PRECIPITATION INPUT ————————————————
Computational Time Step (Minutes): 15
Extended Precipitation Time Series Selected
Climatic Region Number: 1
Full Period of Record Available used for Routing
Precipitation Station : 95003205 Puget West 32 in_5min 10/01/1939-10/01/2097
Evaporation Station : 951032 Puget West 32 in MAP
Evaporation Scale Factor : 0.750
HSPF Parameter Region Number: 1
HSPF Parameter Region Name : USGS Default
********** Default HSPF Parameters Used (Not Modified by User) ***************
********************** WATERSHED DEFINITION ***********************
Predevelopment/Post Development Tributary Area Summary
Predeveloped Post Developed
Total Subbasin Area (acres) 1.080 1.080
Area of Links that Include Precip/Evap (acres) 0.000 0.000
Total (acres) 1.080 1.080
----------------------SCENARIO: PREDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3A.1 ----------
-------Area (Acres) --------
Till Grass 1.080
----------------------------------------------
Subbasin Total 1.080
----------------------SCENARIO: POSTDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3A.1 ----------
-------Area (Acres) --------
Till Grass 0.250
Impervious 0.830
----------------------------------------------
Subbasin Total 1.080
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
***********Groundwater Recharge Summary *************
Recharge is computed as input to Perlnd Groundwater Plus Infiltration in Structures
Total Predeveloped Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3A.1 108.047
_____________________________________
Total: 108.047
Total Post Developed Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3A.1 25.011
_____________________________________
Total: 25.011
Total Predevelopment Recharge is Greater than Post Developed
Average Recharge Per Year, (Number of Years= 158)
Predeveloped: 0.684 ac-ft/year, Post Developed: 0.158 ac-ft/year
***********Compliance Point Results *************
Scenario Predeveloped Compliance Subbasin: Subbasin 3A.1
Scenario Postdeveloped Compliance Subbasin: Subbasin 3A.1
*** Point of Compliance Flow Frequency Data ***
Recurrence Interval Computed Using Gringorten Plotting Position
Predevelopment Runoff Postdevelopment Runoff
Tr (Years) Discharge (cfs) Tr (Years) Discharge (cfs)
----------------------------------------------------------------------------------------------------------------------
2-Year 6.871E-02 2-Year 0.301
5-Year 0.136 5-Year 0.387
10-Year 0.182 10-Year 0.447
25-Year 0.266 25-Year 0.542
50-Year 0.340 50-Year 0.668
100-Year 0.344 100-Year 0.786
200-Year 0.357 200-Year 0.822
** Record too Short to Compute Peak Discharge for These Recurrence Intervals
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
—————————————————————————————————
MGS FLOOD
PROJECT REPORT
Program Version: MGSFlood 4.46
Program License Number: 200410007
Project Simulation Performed on: 01/08/2019 11:30 AM
Report Generation Date: 01/08/2019 11:30 AM
—————————————————————————————————
Input File Name: Sub-basin 3A.2.fld
Project Name: SRM Renton
Analysis Title:
Comments:
———————————————— PRECIPITATION INPUT ————————————————
Computational Time Step (Minutes): 15
Extended Precipitation Time Series Selected
Climatic Region Number: 1
Full Period of Record Available used for Routing
Precipitation Station : 95003205 Puget West 32 in_5min 10/01/1939-10/01/2097
Evaporation Station : 951032 Puget West 32 in MAP
Evaporation Scale Factor : 0.750
HSPF Parameter Region Number: 1
HSPF Parameter Region Name : USGS Default
********** Default HSPF Parameters Used (Not Modified by User) ***************
********************** WATERSHED DEFINITION ***********************
Predevelopment/Post Development Tributary Area Summary
Predeveloped Post Developed
Total Subbasin Area (acres) 0.720 0.720
Area of Links that Include Precip/Evap (acres) 0.000 0.000
Total (acres) 0.720 0.720
----------------------SCENARIO: PREDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3A.2 ----------
-------Area (Acres) --------
Till Grass 0.661
Impervious 0.059
----------------------------------------------
Subbasin Total 0.720
----------------------SCENARIO: POSTDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3A.1 ----------
-------Area (Acres) --------
Till Grass 0.311
Impervious 0.409
----------------------------------------------
Subbasin Total 0.720
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
***********Groundwater Recharge Summary *************
Recharge is computed as input to Perlnd Groundwater Plus Infiltration in Structures
Total Predeveloped Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3A.2 66.129
_____________________________________
Total: 66.129
Total Post Developed Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3A.1 31.113
_____________________________________
Total: 31.113
Total Predevelopment Recharge is Greater than Post Developed
Average Recharge Per Year, (Number of Years= 158)
Predeveloped: 0.419 ac-ft/year, Post Developed: 0.197 ac-ft/year
***********Compliance Point Results *************
Scenario Predeveloped Compliance Subbasin: Subbasin 3A.2
Scenario Postdeveloped Compliance Subbasin: Subbasin 3A.1
*** Point of Compliance Flow Frequency Data ***
Recurrence Interval Computed Using Gringorten Plotting Position
Predevelopment Runoff Postdevelopment Runoff
Tr (Years) Discharge (cfs) Tr (Years) Discharge (cfs)
----------------------------------------------------------------------------------------------------------------------
2-Year 5.775E-02 2-Year 0.165
5-Year 0.105 5-Year 0.209
10-Year 0.140 10-Year 0.249
25-Year 0.197 25-Year 0.320
50-Year 0.243 50-Year 0.382
100-Year 0.245 100-Year 0.423
200-Year 0.250 200-Year 0.449
** Record too Short to Compute Peak Discharge for These Recurrence Intervals
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
—————————————————————————————————
MGS FLOOD
PROJECT REPORT
Program Version: MGSFlood 4.46
Program License Number: 200410007
Project Simulation Performed on: 01/08/2019 11:34 AM
Report Generation Date: 01/08/2019 11:34 AM
—————————————————————————————————
Input File Name: Sub-basin 3A.3.fld
Project Name: SRM Renton
Analysis Title:
Comments:
———————————————— PRECIPITATION INPUT ————————————————
Computational Time Step (Minutes): 15
Extended Precipitation Time Series Selected
Climatic Region Number: 1
Full Period of Record Available used for Routing
Precipitation Station : 95003205 Puget West 32 in_5min 10/01/1939-10/01/2097
Evaporation Station : 951032 Puget West 32 in MAP
Evaporation Scale Factor : 0.750
HSPF Parameter Region Number: 1
HSPF Parameter Region Name : USGS Default
********** Default HSPF Parameters Used (Not Modified by User) ***************
********************** WATERSHED DEFINITION ***********************
Predevelopment/Post Development Tributary Area Summary
Predeveloped Post Developed
Total Subbasin Area (acres) 0.780 0.780
Area of Links that Include Precip/Evap (acres) 0.000 0.000
Total (acres) 0.780 0.780
----------------------SCENARIO: PREDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3A.3 ----------
-------Area (Acres) --------
Till Grass 0.780
----------------------------------------------
Subbasin Total 0.780
----------------------SCENARIO: POSTDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3A.3 ----------
-------Area (Acres) --------
Till Grass 0.020
Impervious 0.760
----------------------------------------------
Subbasin Total 0.780
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
***********Groundwater Recharge Summary *************
Recharge is computed as input to Perlnd Groundwater Plus Infiltration in Structures
Total Predeveloped Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3A.3 78.034
_____________________________________
Total: 78.034
Total Post Developed Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3A.3 2.001
_____________________________________
Total: 2.001
Total Predevelopment Recharge is Greater than Post Developed
Average Recharge Per Year, (Number of Years= 158)
Predeveloped: 0.494 ac-ft/year, Post Developed: 0.013 ac-ft/year
***********Compliance Point Results *************
Scenario Predeveloped Compliance Subbasin: Subbasin 3A.3
Scenario Postdeveloped Compliance Subbasin: Subbasin 3A.3
*** Point of Compliance Flow Frequency Data ***
Recurrence Interval Computed Using Gringorten Plotting Position
Predevelopment Runoff Postdevelopment Runoff
Tr (Years) Discharge (cfs) Tr (Years) Discharge (cfs)
----------------------------------------------------------------------------------------------------------------------
2-Year 4.963E-02 2-Year 0.265
5-Year 9.842E-02 5-Year 0.348
10-Year 0.131 10-Year 0.392
25-Year 0.192 25-Year 0.483
50-Year 0.245 50-Year 0.552
100-Year 0.248 100-Year 0.682
200-Year 0.258 200-Year 0.705
** Record too Short to Compute Peak Discharge for These Recurrence Intervals
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
—————————————————————————————————
MGS FLOOD
PROJECT REPORT
Program Version: MGSFlood 4.46
Program License Number: 200410007
Project Simulation Performed on: 01/08/2019 11:38 AM
Report Generation Date: 01/08/2019 11:38 AM
—————————————————————————————————
Input File Name: Sub-basin 3B.fld
Project Name: SRM Renton
Analysis Title:
Comments:
———————————————— PRECIPITATION INPUT ————————————————
Computational Time Step (Minutes): 15
Extended Precipitation Time Series Selected
Climatic Region Number: 1
Full Period of Record Available used for Routing
Precipitation Station : 95003205 Puget West 32 in_5min 10/01/1939-10/01/2097
Evaporation Station : 951032 Puget West 32 in MAP
Evaporation Scale Factor : 0.750
HSPF Parameter Region Number: 1
HSPF Parameter Region Name : USGS Default
********** Default HSPF Parameters Used (Not Modified by User) ***************
********************** WATERSHED DEFINITION ***********************
Predevelopment/Post Development Tributary Area Summary
Predeveloped Post Developed
Total Subbasin Area (acres) 0.930 0.930
Area of Links that Include Precip/Evap (acres) 0.000 0.000
Total (acres) 0.930 0.930
----------------------SCENARIO: PREDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3B ----------
-------Area (Acres) --------
Till Grass 0.930
----------------------------------------------
Subbasin Total 0.930
----------------------SCENARIO: POSTDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3B ----------
-------Area (Acres) --------
Till Grass 0.330
Impervious 0.600
----------------------------------------------
Subbasin Total 0.930
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
***********Groundwater Recharge Summary *************
Recharge is computed as input to Perlnd Groundwater Plus Infiltration in Structures
Total Predeveloped Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3B 93.040
_____________________________________
Total: 93.040
Total Post Developed Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3B 33.014
_____________________________________
Total: 33.014
Total Predevelopment Recharge is Greater than Post Developed
Average Recharge Per Year, (Number of Years= 158)
Predeveloped: 0.589 ac-ft/year, Post Developed: 0.209 ac-ft/year
***********Compliance Point Results *************
Scenario Predeveloped Compliance Subbasin: Subbasin 3B
Scenario Postdeveloped Compliance Subbasin: Subbasin 3B
*** Point of Compliance Flow Frequency Data ***
Recurrence Interval Computed Using Gringorten Plotting Position
Predevelopment Runoff Postdevelopment Runoff
Tr (Years) Discharge (cfs) Tr (Years) Discharge (cfs)
----------------------------------------------------------------------------------------------------------------------
2-Year 5.917E-02 2-Year 0.231
5-Year 0.117 5-Year 0.292
10-Year 0.157 10-Year 0.347
25-Year 0.229 25-Year 0.434
50-Year 0.293 50-Year 0.526
100-Year 0.296 100-Year 0.595
200-Year 0.307 200-Year 0.628
** Record too Short to Compute Peak Discharge for These Recurrence Intervals
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
—————————————————————————————————
MGS FLOOD
PROJECT REPORT
Program Version: MGSFlood 4.46
Program License Number: 200410007
Project Simulation Performed on: 01/02/2019 10:03 AM
Report Generation Date: 01/02/2019 10:03 AM
—————————————————————————————————
Input File Name: Sub-basin 3C.fld
Project Name: SRM Renton
Analysis Title:
Comments:
———————————————— PRECIPITATION INPUT ————————————————
Computational Time Step (Minutes): 15
Extended Precipitation Time Series Selected
Climatic Region Number: 1
Full Period of Record Available used for Routing
Precipitation Station : 95003205 Puget West 32 in_5min 10/01/1939-10/01/2097
Evaporation Station : 951032 Puget West 32 in MAP
Evaporation Scale Factor : 0.750
HSPF Parameter Region Number: 1
HSPF Parameter Region Name : USGS Default
********** Default HSPF Parameters Used (Not Modified by User) ***************
********************** WATERSHED DEFINITION ***********************
Predevelopment/Post Development Tributary Area Summary
Predeveloped Post Developed
Total Subbasin Area (acres) 3.892 3.892
Area of Links that Include Precip/Evap (acres) 0.000 0.000
Total (acres) 3.892 3.892
----------------------SCENARIO: PREDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3C ----------
-------Area (Acres) --------
Till Grass 3.880
Impervious 0.012
----------------------------------------------
Subbasin Total 3.892
----------------------SCENARIO: POSTDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3C ----------
-------Area (Acres) --------
Till Grass 1.100
Impervious 2.792
----------------------------------------------
Subbasin Total 3.892
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
**********************FLOOD FREQUENCY AND DURATION STATISTICS*******************
----------------------SCENARIO: PREDEVELOPED
Number of Subbasins: 1
Number of Links: 0
----------------------SCENARIO: POSTDEVELOPED
Number of Subbasins: 1
Number of Links: 0
***********Groundwater Recharge Summary *************
Recharge is computed as input to Perlnd Groundwater Plus Infiltration in Structures
Total Predeveloped Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3C 388.168
_____________________________________
Total: 388.168
Total Post Developed Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3C 110.048
_____________________________________
Total: 110.048
Total Predevelopment Recharge is Greater than Post Developed
Average Recharge Per Year, (Number of Years= 158)
Predeveloped: 2.457 ac-ft/year, Post Developed: 0.697 ac-ft/year
***********Compliance Point Results *************
Scenario Predeveloped Compliance Subbasin: Subbasin 3C
Scenario Postdeveloped Compliance Subbasin: Subbasin 3C
*** Point of Compliance Flow Frequency Data ***
Recurrence Interval Computed Using Gringorten Plotting Position
Predevelopment Runoff Postdevelopment Runoff
Tr (Years) Discharge (cfs) Tr (Years) Discharge (cfs)
----------------------------------------------------------------------------------------------------------------------
2-Year 0.250 2-Year 1.037
5-Year 0.494 5-Year 1.325
10-Year 0.659 10-Year 1.554
25-Year 0.964 25-Year 1.906
50-Year 1.228 50-Year 2.322
100-Year 1.242 100-Year 2.689
200-Year 1.288 200-Year 2.824
** Record too Short to Compute Peak Discharge for These Recurrence Intervals
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
—————————————————————————————————
MGS FLOOD
PROJECT REPORT
Program Version: MGSFlood 4.46
Program License Number: 200410007
Project Simulation Performed on: 01/02/2019 10:22 AM
Report Generation Date: 01/02/2019 10:22 AM
—————————————————————————————————
Input File Name: Sub-basin 3D.fld
Project Name: SRM Renton
Analysis Title:
Comments:
———————————————— PRECIPITATION INPUT ————————————————
Computational Time Step (Minutes): 15
Extended Precipitation Time Series Selected
Climatic Region Number: 1
Full Period of Record Available used for Routing
Precipitation Station : 95003205 Puget West 32 in_5min 10/01/1939-10/01/2097
Evaporation Station : 951032 Puget West 32 in MAP
Evaporation Scale Factor : 0.750
HSPF Parameter Region Number: 1
HSPF Parameter Region Name : USGS Default
********** Default HSPF Parameters Used (Not Modified by User) ***************
********************** WATERSHED DEFINITION ***********************
Predevelopment/Post Development Tributary Area Summary
Predeveloped Post Developed
Total Subbasin Area (acres) 4.330 4.330
Area of Links that Include Precip/Evap (acres) 0.000 0.000
Total (acres) 4.330 4.330
----------------------SCENARIO: PREDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3D ----------
-------Area (Acres) --------
Till Grass 0.070
Impervious 4.260
----------------------------------------------
Subbasin Total 4.330
----------------------SCENARIO: POSTDEVELOPED
Number of Subbasins: 1
---------- Subbasin : Subbasin 3D ----------
-------Area (Acres) --------
Till Grass 0.720
Impervious 3.610
----------------------------------------------
Subbasin Total 4.330
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
**********************FLOOD FREQUENCY AND DURATION STATISTICS*******************
----------------------SCENARIO: PREDEVELOPED
Number of Subbasins: 1
Number of Links: 0
----------------------SCENARIO: POSTDEVELOPED
Number of Subbasins: 1
Number of Links: 0
***********Groundwater Recharge Summary *************
Recharge is computed as input to Perlnd Groundwater Plus Infiltration in Structures
Total Predeveloped Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3D 7.003
_____________________________________
Total: 7.003
Total Post Developed Recharge During Simulation
Model Element Recharge Amount (ac-ft)
-----------------------------------------------------------------------------------------------
Subbasin: Subbasin 3D 72.031
_____________________________________
Total: 72.031
Total Predevelopment Recharge is Less than Post Developed
Average Recharge Per Year, (Number of Years= 158)
Predeveloped: 0.044 ac-ft/year, Post Developed: 0.456 ac-ft/year
***********Compliance Point Results *************
Scenario Predeveloped Compliance Subbasin: Subbasin 3D
Scenario Postdeveloped Compliance Subbasin: Subbasin 3D
*** Point of Compliance Flow Frequency Data ***
Recurrence Interval Computed Using Gringorten Plotting Position
Predevelopment Runoff Postdevelopment Runoff
Tr (Years) Discharge (cfs) Tr (Years) Discharge (cfs)
----------------------------------------------------------------------------------------------------------------------
2-Year 1.488 2-Year 1.294
5-Year 1.950 5-Year 1.663
10-Year 2.194 10-Year 1.924
25-Year 2.702 25-Year 2.318
50-Year 3.080 50-Year 2.800
100-Year 3.816 100-Year 3.352
200-Year 3.943 200-Year 3.492
** Record too Short to Compute Peak Discharge for These Recurrence Intervals
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
Cedar River Apartments – SRM Development
Appendix D
Appendix D
Bond Quantities, Facility Summaries, and Declaratio n of Covenant
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
Planning Division |1055 South Grady Way – 6th Floor | Renton, WA 98057 (425) 430-7200••Section I: Project Information•••Section II: Bond Quantities Worksheets••Section II.a EROSION CONTROL (Stabilization/Erosion Sediment Control (ESC))•Section II.b TRANSPORTATION (Street and Site Improvements)•Section II.c DRAINAGE (Drainage and Stormwater Facilities): •Section II.d WATER - ONLY APPLICABLE IF WATER SERVICE IS PROVIDED BY CITY OF RENTON•Section II.e SANITARY SEWER - ONLY APPLICABLE IF SEWER SERVICE IS PROVIDED BY CITY OF RENTON••••••Section III. Bond Worksheet• This section calculates the required Permit Bond for construction permit issuance as well as the required Maintenance Bond for project close-out submittals to release the permit bond on a project. All unit prices include labor, equipment, materials, overhead and profit. Complete the 'Quantity' columns for each of the appropriate section(s). Include existing Right-of-Way (ROW), Future Public Improvements and Private Improvements.The 'Quantity Remaining' column is only to be used when a project is under construction. The City allows one (1) bond reduction during the life of the project with the exception of the maintenance period reduction.Excel will auto-calculate and auto-populate the relevant fields and subtotals throughout the document. Only the 'Quantity' columns should need completing.Additional items not included in the lists can be added under the "write-in" sections. Provide a complete description, cost estimate and unit of measure for each write-in item. Note: Private improvements, with the exception of stormwater facilities, are not included in the bond amount calculation, but must be entered on the form. Stormwater facilities (public and private) are required to be included in the bond amount.BOND QUANTITY WORKSHEET INSTRUCTIONSThis worksheet is intended to be a "working" copy of the bond quantity worksheet, which will be used throughout all phases of the project, from initial submittal to project close-out approval. Submit this workbook, in its entirety, as follows:The following forms are to be completed by the engineer/developer/applicant as applicable to the project: The Bond Worksheet form will auto-calculate and auto-populate from the information provided in Section I and Section II.This section includes all pertinent information for the projectSection II contains a separate spreadsheet TAB for each of the following specialties: (1) electronic copy (.xlsx format) and (1) hard copy of the entire workbook for civil construction permit submittal. Hard copies are to be included as part of the Technical Information Report (TIR).(1) electronic copy (.xlsx format) and (1) hard copy of the entire workbook for final close-out submittal.This section must be completed in its entiretyInformation from this section auto-populates to all other relevant areas of the workbookPage 1 of 14Ref 8-H Bond Quantity WorksheetINSTRUCTIONSUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
Planning Division |1055 South Grady Way – 6th Floor | Renton, WA 98057 (425) 430-7200Date Prepared: Name:PE Registration No:Firm Name:Firm Address:Phone No.Email Address:Project Name: Project Owner:CED Plan # (LUA):Phone:CED Permit # (U):Address: Site Address:Street Intersection:Addt'l Project Owner:Parcel #(s):Phone:Address: Clearing and grading greater than or equal to 5,000 board feet of timber? Yes/No:Water Service Provided by:If Yes, Provide Forest Practice Permit #:Sewer Service Provided by: SITE IMPROVEMENT BOND QUANTITY WORKSHEETPROJECT INFORMATIONCITY OF RENTONCITY OF RENTON1 Select the current project status/phase from the following options: For Approval - Preliminary Data Enclosed, pending approval from the City; For Construction - Estimated Data Enclosed, Plans have been approved for contruction by the City; Project Closeout - Final Costs and Quantities Enclosed for Project Close-out SubmittalPhoneEngineer Stamp Required (all cost estimates must have original wet stamp and signature)Clearing and GradingUtility ProvidersN/AProject Location and DescriptionProject Owner InformationProject NameCity, State, ZipParcel NumberProject Owner##-######PhoneDatePrepared by:FOR APPROVALProject Phase 1Email AddressNamePE Registration No.Firm NameFirm AddressPhone No.Site AddressAddressAdditional Project OwnerStreet Intersection########AddressAbbreviated Legal Description:Abbreviated LegalCity, State, ZipPage 2 of 14Ref 8-H Bond Quantity WorksheetSECTION I PROJECT INFORMATIONUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CED Permit #:########UnitReference #PriceUnitQuantity CostBackfill & compaction-embankmentESC-16.50$ CY Check dams, 4" minus rockESC-2SWDM 5.4.6.380.00$ Each Catch Basin ProtectionESC-335.50$ Each Crushed surfacing 1 1/4" minusESC-4WSDOT 9-03.9(3)95.00$ CY DitchingESC-59.00$ CY Excavation-bulkESC-62.00$ CY Fence, siltESC-7SWDM 5.4.3.11.50$ LF Fence, Temporary (NGPE)ESC-81.50$ LF Geotextile FabricESC-92.50$ SY Hay Bale Silt TrapESC-100.50$ Each HydroseedingESC-11SWDM 5.4.2.40.80$ SY Interceptor Swale / DikeESC-121.00$ LF Jute MeshESC-13SWDM 5.4.2.23.50$ SY Level SpreaderESC-141.75$ LF Mulch, by hand, straw, 3" deepESC-15SWDM 5.4.2.12.50$ SY Mulch, by machine, straw, 2" deepESC-16SWDM 5.4.2.12.00$ SY Piping, temporary, CPP, 6"ESC-1712.00$ LF Piping, temporary, CPP, 8"ESC-1814.00$ LF Piping, temporary, CPP, 12"ESC-1918.00$ LF Plastic covering, 6mm thick, sandbaggedESC-20SWDM 5.4.2.34.00$ SY Rip Rap, machine placed; slopesESC-21WSDOT 9-13.1(2)45.00$ CY Rock Construction Entrance, 50'x15'x1'ESC-22SWDM 5.4.4.11,800.00$ Each Rock Construction Entrance, 100'x15'x1'ESC-23SWDM 5.4.4.13,200.00$ Each Sediment pond riser assemblyESC-24SWDM 5.4.5.22,200.00$ Each Sediment trap, 5' high berm ESC-25SWDM 5.4.5.119.00$ LF Sed. trap, 5' high, riprapped spillway berm section ESC-26SWDM 5.4.5.170.00$ LF Seeding, by handESC-27SWDM 5.4.2.41.00$ SY Sodding, 1" deep, level groundESC-28SWDM 5.4.2.58.00$ SY Sodding, 1" deep, sloped groundESC-29SWDM 5.4.2.510.00$ SY TESC SupervisorESC-30110.00$ HR Water truck, dust controlESC-31SWDM 5.4.7140.00$ HR UnitReference #PriceUnitQuantity Cost EROSION/SEDIMENT SUBTOTAL:SALES TAX @ 10%EROSION/SEDIMENT TOTAL:(A)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR EROSION & SEDIMENT CONTROLDescription No.(A)WRITE-IN-ITEMS Page 3 of 14Ref 8-H Bond Quantity WorksheetSECTION II.a EROSION_CONTROLUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CED Permit #:########ExistingFuture PublicPrivateRight-of-WayImprovementsImprovements(D) (E)DescriptionNo. Unit PriceUnitQuant.CostQuant.CostQuant.CostQuant.CostGENERAL ITEMS Backfill & Compaction- embankmentGI-16.00$ CYBackfill & Compaction- trenchGI-29.00$ CYClear/Remove Brush, by hand (SY)GI-31.00$ SYBollards - fixedGI-4240.74$ EachBollards - removableGI-5452.34$ EachClearing/Grubbing/Tree RemovalGI-610,000.00$ AcreExcavation - bulkGI-72.00$ CYExcavation - TrenchGI-85.00$ CYFencing, cedar, 6' highGI-920.00$ LFFencing, chain link, 4'GI-1038.31$ LFFencing, chain link, vinyl coated, 6' highGI-1120.00$ LFFencing, chain link, gate, vinyl coated, 20' GI-121,400.00$ EachFill & compact - common barrowGI-1325.00$ CYFill & compact - gravel baseGI-1427.00$ CYFill & compact - screened topsoilGI-1539.00$ CYGabion, 12" deep, stone filled mesh GI-1665.00$ SYGabion, 18" deep, stone filled mesh GI-1790.00$ SYGabion, 36" deep, stone filled meshGI-18150.00$ SYGrading, fine, by handGI-192.50$ SYGrading, fine, with graderGI-202.00$ SYMonuments, 3' LongGI-21250.00$ EachSensitive Areas SignGI-227.00$ EachSodding, 1" deep, sloped groundGI-238.00$ SYSurveying, line & gradeGI-24850.00$ DaySurveying, lot location/linesGI-251,800.00$ AcreTopsoil Type A (imported)GI-2628.50$ CYTraffic control crew ( 2 flaggers )GI-27120.00$ HRTrail, 4" chipped woodGI-288.00$ SYTrail, 4" crushed cinderGI-299.00$ SYTrail, 4" top courseGI-3012.00$ SYConduit, 2"GI-315.00$ LFWall, retaining, concreteGI-3255.00$ SFWall, rockeryGI-3315.00$ SFSUBTOTAL THIS PAGE:(B)(C)(D)(E)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR STREET AND SITE IMPROVEMENTSQuantity Remaining (Bond Reduction) (B)(C)Page 4 of 14Ref 8-H Bond Quantity WorksheetSECTION II.b TRANSPORTATIONUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CED Permit #:########ExistingFuture PublicPrivateRight-of-WayImprovementsImprovements(D) (E)DescriptionNo. Unit PriceUnitQuant.CostQuant.CostQuant.CostQuant.CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR STREET AND SITE IMPROVEMENTSQuantity Remaining (Bond Reduction) (B)(C)ROAD IMPROVEMENT/PAVEMENT/SURFACINGAC Grinding, 4' wide machine < 1000syRI-130.00$ SYAC Grinding, 4' wide machine 1000-2000syRI-216.00$ SYAC Grinding, 4' wide machine > 2000syRI-310.00$ SYAC Removal/DisposalRI-435.00$ SYBarricade, Type III ( Permanent )RI-556.00$ LFGuard RailRI-630.00$ LFCurb & Gutter, rolledRI-717.00$ LFCurb & Gutter, verticalRI-812.50$ LFCurb and Gutter, demolition and disposalRI-918.00$ LFCurb, extruded asphaltRI-105.50$ LFCurb, extruded concreteRI-117.00$ LFSawcut, asphalt, 3" depthRI-121.85$ LFSawcut, concrete, per 1" depthRI-133.00$ LFSealant, asphaltRI-142.00$ LFShoulder, gravel, 4" thickRI-1515.00$ SYSidewalk, 4" thickRI-1638.00$ SYSidewalk, 4" thick, demolition and disposalRI-1732.00$ SYSidewalk, 5" thickRI-1841.00$ SYSidewalk, 5" thick, demolition and disposalRI-1940.00$ SYSign, Handicap RI-2085.00$ EachStriping, per stallRI-217.00$ EachStriping, thermoplastic, ( for crosswalk )RI-223.00$ SFStriping, 4" reflectorized lineRI-230.50$ LFAdditional 2.5" Crushed SurfacingRI-243.60$ SYHMA 1/2" Overlay 1.5" RI-2514.00$ SYHMA 1/2" Overlay 2"RI-2618.00$ SYHMA Road, 2", 4" rock, First 2500 SYRI-2728.00$ SYHMA Road, 2", 4" rock, Qty. over 2500SYRI-2821.00$ SYHMA Road, 4", 6" rock, First 2500 SYRI-2945.00$ SYHMA Road, 4", 6" rock, Qty. over 2500 SYRI-3037.00$ SYHMA Road, 4", 4.5" ATBRI-3138.00$ SYGravel Road, 4" rock, First 2500 SYRI-3215.00$ SYGravel Road, 4" rock, Qty. over 2500 SYRI-3310.00$ SYThickened EdgeRI-348.60$ LFSUBTOTAL THIS PAGE:(B)(C)(D)(E)Page 5 of 14Ref 8-H Bond Quantity WorksheetSECTION II.b TRANSPORTATIONUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CED Permit #:########ExistingFuture PublicPrivateRight-of-WayImprovementsImprovements(D) (E)DescriptionNo. Unit PriceUnitQuant.CostQuant.CostQuant.CostQuant.CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR STREET AND SITE IMPROVEMENTSQuantity Remaining (Bond Reduction) (B)(C)PARKING LOT SURFACINGNo.2" AC, 2" top course rock & 4" borrowPL-121.00$ SY2" AC, 1.5" top course & 2.5" base coursePL-228.00$ SY4" select borrowPL-35.00$ SY1.5" top course rock & 2.5" base coursePL-414.00$ SYSUBTOTAL PARKING LOT SURFACING:(B)(C)(D)(E)LANDSCAPING & VEGETATIONNo.Street TreesLA-1Median LandscapingLA-2Right-of-Way LandscapingLA-3Wetland LandscapingLA-4SUBTOTAL LANDSCAPING & VEGETATION:(B)(C)(D)(E)TRAFFIC & LIGHTINGNo.SignsTR-1Street Light System ( # of Poles)TR-2Traffic SignalTR-3Traffic Signal ModificationTR-4SUBTOTAL TRAFFIC & LIGHTING:(B)(C)(D)(E)WRITE-IN-ITEMSSUBTOTAL WRITE-IN ITEMS:STREET AND SITE IMPROVEMENTS SUBTOTAL:SALES TAX @ 10%STREET AND SITE IMPROVEMENTS TOTAL:(B)(C)(D)(E)Page 6 of 14Ref 8-H Bond Quantity WorksheetSECTION II.b TRANSPORTATIONUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CED Permit #:########ExistingFuture PublicPrivateRight-of-WayImprovementsImprovements(D) (E)DescriptionNo. Unit PriceUnitQuant.CostQuant.CostQuant.CostQuant.CostDRAINAGE (CPE = Corrugated Polyethylene Pipe, N12 or Equivalent) For Culvert prices, Average of 4' cover was assumed. Assume perforated PVC is same price as solid pipe.) Access Road, R/DD-126.00$ SY* (CBs include frame and lid)BeehiveD-290.00$ EachThrough-curb Inlet FrameworkD-3400.00$ EachCB Type ID-41,500.00$ EachCB Type ILD-51,750.00$ EachCB Type II, 48" diameterD-62,300.00$ Each for additional depth over 4' D-7480.00$ FTCB Type II, 54" diameterD-82,500.00$ Each for additional depth over 4'D-9495.00$ FTCB Type II, 60" diameterD-102,800.00$ Each for additional depth over 4'D-11600.00$ FTCB Type II, 72" diameterD-126,000.00$ Each for additional depth over 4'D-13850.00$ FTCB Type II, 96" diameterD-1414,000.00$ Each for additional depth over 4'D-15925.00$ FTTrash Rack, 12"D-16350.00$ EachTrash Rack, 15"D-17410.00$ EachTrash Rack, 18"D-18480.00$ EachTrash Rack, 21"D-19550.00$ EachCleanout, PVC, 4"D-20150.00$ EachCleanout, PVC, 6"D-21170.00$ EachCleanout, PVC, 8"D-22200.00$ EachCulvert, PVC, 4" D-2310.00$ LFCulvert, PVC, 6" D-2413.00$ LFCulvert, PVC, 8" D-2515.00$ LFCulvert, PVC, 12" D-2623.00$ LFCulvert, PVC, 15" D-2735.00$ LFCulvert, PVC, 18" D-2841.00$ LFCulvert, PVC, 24"D-2956.00$ LFCulvert, PVC, 30" D-3078.00$ LFCulvert, PVC, 36" D-31130.00$ LFCulvert, CMP, 8"D-3219.00$ LFCulvert, CMP, 12"D-3329.00$ LFSUBTOTAL THIS PAGE:(B)(C)(D)(E)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESQuantity Remaining (Bond Reduction) (B)(C)Page 7 of 14Ref 8-H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CED Permit #:########ExistingFuture PublicPrivateRight-of-WayImprovementsImprovements(D) (E)DescriptionNo. Unit PriceUnitQuant.CostQuant.CostQuant.CostQuant.CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESQuantity Remaining (Bond Reduction) (B)(C)DRAINAGE (Continued)Culvert, CMP, 15"D-3435.00$ LFCulvert, CMP, 18"D-3541.00$ LFCulvert, CMP, 24"D-3656.00$ LFCulvert, CMP, 30"D-3778.00$ LFCulvert, CMP, 36"D-38130.00$ LFCulvert, CMP, 48"D-39190.00$ LFCulvert, CMP, 60"D-40270.00$ LFCulvert, CMP, 72"D-41350.00$ LFCulvert, Concrete, 8"D-4242.00$ LFCulvert, Concrete, 12"D-4348.00$ LFCulvert, Concrete, 15"D-4478.00$ LFCulvert, Concrete, 18"D-4548.00$ LFCulvert, Concrete, 24"D-4678.00$ LFCulvert, Concrete, 30"D-47125.00$ LFCulvert, Concrete, 36"D-48150.00$ LFCulvert, Concrete, 42"D-49175.00$ LFCulvert, Concrete, 48"D-50205.00$ LFCulvert, CPE Triple Wall, 6" D-5114.00$ LFCulvert, CPE Triple Wall, 8" D-5216.00$ LFCulvert, CPE Triple Wall, 12" D-5324.00$ LFCulvert, CPE Triple Wall, 15" D-5435.00$ LFCulvert, CPE Triple Wall, 18" D-5541.00$ LFCulvert, CPE Triple Wall, 24" D-5656.00$ LFCulvert, CPE Triple Wall, 30" D-5778.00$ LFCulvert, CPE Triple Wall, 36" D-58130.00$ LFCulvert, LCPE, 6"D-5960.00$ LFCulvert, LCPE, 8"D-6072.00$ LFCulvert, LCPE, 12"D-6184.00$ LFCulvert, LCPE, 15"D-6296.00$ LFCulvert, LCPE, 18"D-63108.00$ LFCulvert, LCPE, 24"D-64120.00$ LFCulvert, LCPE, 30"D-65132.00$ LFCulvert, LCPE, 36"D-66144.00$ LFCulvert, LCPE, 48"D-67156.00$ LFCulvert, LCPE, 54"D-68168.00$ LFSUBTOTAL THIS PAGE:(B)(C)(D)(E)Page 8 of 14Ref 8-H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CED Permit #:########ExistingFuture PublicPrivateRight-of-WayImprovementsImprovements(D) (E)DescriptionNo. Unit PriceUnitQuant.CostQuant.CostQuant.CostQuant.CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESQuantity Remaining (Bond Reduction) (B)(C)DRAINAGE (Continued)Culvert, LCPE, 60"D-69180.00$ LFCulvert, LCPE, 72"D-70192.00$ LFCulvert, HDPE, 6"D-7142.00$ LFCulvert, HDPE, 8"D-7242.00$ LFCulvert, HDPE, 12"D-7374.00$ LFCulvert, HDPE, 15"D-74106.00$ LFCulvert, HDPE, 18"D-75138.00$ LFCulvert, HDPE, 24"D-76221.00$ LFCulvert, HDPE, 30"D-77276.00$ LFCulvert, HDPE, 36"D-78331.00$ LFCulvert, HDPE, 48"D-79386.00$ LFCulvert, HDPE, 54"D-80441.00$ LFCulvert, HDPE, 60"D-81496.00$ LFCulvert, HDPE, 72"D-82551.00$ LFPipe, Polypropylene, 6"D-8384.00$ LFPipe, Polypropylene, 8"D-8489.00$ LFPipe, Polypropylene, 12"D-8595.00$ LFPipe, Polypropylene, 15"D-86100.00$ LFPipe, Polypropylene, 18"D-87106.00$ LFPipe, Polypropylene, 24"D-88111.00$ LFPipe, Polypropylene, 30"D-89119.00$ LFPipe, Polypropylene, 36"D-90154.00$ LFPipe, Polypropylene, 48"D-91226.00$ LFPipe, Polypropylene, 54"D-92332.00$ LFPipe, Polypropylene, 60"D-93439.00$ LFPipe, Polypropylene, 72"D-94545.00$ LFCulvert, DI, 6"D-9561.00$ LFCulvert, DI, 8"D-9684.00$ LFCulvert, DI, 12"D-97106.00$ LFCulvert, DI, 15"D-98129.00$ LFCulvert, DI, 18"D-99152.00$ LFCulvert, DI, 24"D-100175.00$ LFCulvert, DI, 30"D-101198.00$ LFCulvert, DI, 36"D-102220.00$ LFCulvert, DI, 48"D-103243.00$ LFCulvert, DI, 54"D-104266.00$ LFCulvert, DI, 60"D-105289.00$ LFCulvert, DI, 72"D-106311.00$ LFSUBTOTAL THIS PAGE:(B)(C)(D)(E)Page 9 of 14Ref 8-H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CED Permit #:########ExistingFuture PublicPrivateRight-of-WayImprovementsImprovements(D) (E)DescriptionNo. Unit PriceUnitQuant.CostQuant.CostQuant.CostQuant.CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESQuantity Remaining (Bond Reduction) (B)(C)Specialty Drainage ItemsDitching SD-19.50$ CYFlow Dispersal Trench (1,436 base+)SD-328.00$ LF French Drain (3' depth)SD-426.00$ LFGeotextile, laid in trench, polypropyleneSD-53.00$ SYMid-tank Access Riser, 48" dia, 6' deepSD-62,000.00$ EachPond Overflow SpillwaySD-716.00$ SYRestrictor/Oil Separator, 12"SD-81,150.00$ EachRestrictor/Oil Separator, 15"SD-91,350.00$ EachRestrictor/Oil Separator, 18"SD-101,700.00$ EachRiprap, placedSD-1142.00$ CYTank End Reducer (36" diameter)SD-121,200.00$ EachInfiltration pond testingSD-13125.00$ HRPermeable PavementSD-14Permeable Concrete SidewalkSD-15Culvert, Box __ ft x __ ftSD-16SUBTOTAL SPECIALTY DRAINAGE ITEMS:(B)(C)(D)(E)STORMWATER FACILITIES (Include Flow Control and Water Quality Facility Summary Sheet and Sketch)Detention PondSF-1Each Detention TankSF-2Each Detention VaultSF-3Each Infiltration PondSF-4Each Infiltration TankSF-5Each Infiltration VaultSF-6Each Infiltration TrenchesSF-7Each Basic Biofiltration SwaleSF-8Each Wet Biofiltration SwaleSF-9Each WetpondSF-10Each WetvaultSF-11Each Sand FilterSF-12Each Sand Filter VaultSF-13Each Linear Sand FilterSF-14Each Proprietary FacilitySF-15Each Bioretention FacilitySF-16Each SUBTOTAL STORMWATER FACILITIES:(B)(C)(D)(E)Page 10 of 14Ref 8-H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CED Permit #:########ExistingFuture PublicPrivateRight-of-WayImprovementsImprovements(D) (E)DescriptionNo. Unit PriceUnitQuant.CostQuant.CostQuant.CostQuant.CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESQuantity Remaining (Bond Reduction) (B)(C)WRITE-IN-ITEMS (INCLUDE ON-SITE BMPs)WI-1WI-2WI-3WI-4WI-5WI-6WI-7WI-8WI-9WI-10WI-11WI-12WI-13WI-14WI-15SUBTOTAL WRITE-IN ITEMS:DRAINAGE AND STORMWATER FACILITIES SUBTOTAL:SALES TAX @ 10%DRAINAGE AND STORMWATER FACILITIES TOTAL:(B) (C) (D) (E)Page 11 of 14Ref 8-H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CED Permit #:########ExistingFuture PublicPrivateRight-of-WayImprovementsImprovements(D) (E)DescriptionNo. Unit PriceUnitQuant.CostQuant.CostQuant.CostQuant.CostConnection to Existing WatermainW-12,000.00$ EachDuctile Iron Watermain, CL 52, 4 Inch DiameterW-250.00$ LFDuctile Iron Watermain, CL 52, 6 Inch DiameterW-356.00$ LFDuctile Iron Watermain, CL 52, 8 Inch DiameterW-460.00$ LFDuctile Iron Watermain, CL 52, 10 Inch DiameterW-570.00$ LFDuctile Iron Watermain, CL 52, 12 Inch DiameterW-680.00$ LFGate Valve, 4 inch DiameterW-7500.00$ EachGate Valve, 6 inch DiameterW-8700.00$ EachGate Valve, 8 Inch DiameterW-9800.00$ EachGate Valve, 10 Inch DiameterW-101,000.00$ EachGate Valve, 12 Inch DiameterW-111,200.00$ EachFire Hydrant AssemblyW-124,000.00$ EachPermanent Blow-Off AssemblyW-131,800.00$ EachAir-Vac Assembly, 2-Inch DiameterW-142,000.00$ EachAir-Vac Assembly, 1-Inch DiameterW-151,500.00$ EachCompound Meter Assembly 3-inch DiameterW-168,000.00$ EachCompound Meter Assembly 4-inch DiameterW-179,000.00$ EachCompound Meter Assembly 6-inch DiameterW-1810,000.00$ EachPressure Reducing Valve Station 8-inch to 10-inchW-1920,000.00$ EachWATER SUBTOTAL:SALES TAX @ 10%WATER TOTAL:(B) (C) (D) (E)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR WATERQuantity Remaining (Bond Reduction) (B)(C)Page 12 of 14Ref 8-H Bond Quantity WorksheetSECTION II.d WATERUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
CED Permit #:########ExistingFuture PublicPrivateRight-of-WayImprovementsImprovements(D) (E)DescriptionNo. Unit PriceUnitQuant.CostQuant.CostQuant.CostQuant.CostClean OutsSS-11,000.00$ EachGrease Interceptor, 500 gallonSS-28,000.00$ EachGrease Interceptor, 1000 gallonSS-310,000.00$ EachGrease Interceptor, 1500 gallonSS-415,000.00$ EachSide Sewer Pipe, PVC. 4 Inch DiameterSS-580.00$ LFSide Sewer Pipe, PVC. 6 Inch DiameterSS-695.00$ LFSewer Pipe, PVC, 8 inch DiameterSS-7105.00$ LFSewer Pipe, PVC, 12 Inch DiameterSS-8120.00$ LFSewer Pipe, DI, 8 inch DiameterSS-9115.00$ LFSewer Pipe, DI, 12 Inch DiameterSS-10130.00$ LFManhole, 48 Inch DiameterSS-116,000.00$ EachManhole, 54 Inch DiameterSS-136,500.00$ EachManhole, 60 Inch DiameterSS-157,500.00$ EachManhole, 72 Inch DiameterSS-178,500.00$ EachManhole, 96 Inch DiameterSS-1914,000.00$ EachPipe, C-900, 12 Inch DiameterSS-21180.00$ LFOutside DropSS-241,500.00$ LSInside DropSS-251,000.00$ LSSewer Pipe, PVC, ____ Inch DiameterSS-26Lift Station (Entire System)SS-27LSSANITARY SEWER SUBTOTAL:SALES TAX @ 10%SANITARY SEWER TOTAL:(B) (C) (D) (E)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR SANITARY SEWERQuantity Remaining (Bond Reduction) (B)(C)Page 13 of 14Ref 8-H Bond Quantity WorksheetSECTION II.e SANITARY SEWERUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
Planning Division |1055 South Grady Way – 6th Floor | Renton, WA 98057 (425) 430-7200Date:Name:Project Name: PE Registration No:CED Plan # (LUA):Firm Name:CED Permit # (U):Firm Address:Site Address:Phone No.Parcel #(s):Email Address:Project Phase: Site Restoration/Erosion Sediment Control Subtotal (a)Existing Right-of-Way Improvements Subtotal (b)(b)-$ Future Public Improvements Subtotal(c)-$ Stormwater & Drainage Facilities (Public & Private) Subtotal(d)(d)-$ (e)(f)Site RestorationCivil Construction PermitMaintenance Bond-$ Bond Reduction2Construction Permit Bond Amount 3Minimum Bond Amount is $10,000.001 Estimate Only - May involve multiple and variable components, which will be established on an individual basis by Development Engineering.2 The City of Renton allows one request only for bond reduction prior to the maintenance period. Reduction of not more than 70% of the original bond amount, provided that the remaining 30% willcover all remaining items to be constructed. 3 Required Bond Amounts are subject to review and modification by Development Engineering.* Note: The word BOND as used in this document means any financial guarantee acceptable to the City of Renton.** Note: All prices include labor, equipment, materials, overhead and profit. Phone No.Email AddressProject Name##-######Site AddressParcel NumberFOR APPROVAL########Firm Address-$ P (a) x 100%SITE IMPROVEMENT BOND QUANTITY WORKSHEET BOND CALCULATIONSDateNamePE Registration No.Firm NameR((b x 150%) + (d x 100%))S(e) x 150% + (f) x 100%Bond Reduction: Existing Right-of-Way Improvements (Quantity Remaining)2Bond Reduction: Stormwater & Drainage Facilities (Quantity Remaining)2T(P +R - S)Prepared by:Project InformationCONSTRUCTION BOND AMOUNT */**(prior to permit issuance)EST1((b) + (c) + (d)) x 20%-$ MAINTENANCE BOND */**(after final acceptance of construction)-$ -$ -$ -$ -$ -$ -$ Page 14 of 14Ref 8-H Bond Quantity WorksheetSECTION III. BOND WORKSHEETUnit Prices Updated: 06/14/2016Version: 04/26/2017Printed 10/26/2018DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
OtherN/AN/AN/AN/AN/AN/Axx3Lower Cedar River BasinCedar River Basin17230590261915 Maple Valley HighwayRenton, WA 98057Cedar River ApartmentsDocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
(91% of runoff volume)N/AContech (Filterra system)3Lower Cedar River BasinCedar River Basin1915 Maple Valley HighwayRenton, WA 98057Cedar River ApartmentsDocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1
Cedar River Apartments – SRM Development
Appendix E
Appendix E
Special Reports and Studies
Not included.
DocuSign Envelope ID: 99BA427F-FE67-49CC-B142-9BE0760232C1