HomeMy WebLinkAboutStormwater Pollution Prevention and Spill Control Rev1Stormwater Pollution Prevention and Spill Control – Wet Weather Plan
Canopy PUD, C21000838
4196 Lincoln Ave, Renton
The purpose of this stormwater pollution prevention plan (SWPPP) is to prevent, reduce, or
eliminate the discharge of pollutants to onsite or adjacent stormwater systems or watercourses
from construction of the Canopy project. This plan specifically addresses the wet weather
period of October 1, 2022, thru April 30, 2023, and was developed in accord with Appendix D of
the City of Renton Surface Water Design Manual.
Specific wet season provisions of Appendix D are:
1. The allowed time that disturbed areas can remain unworked without cover is two (2)
days.
2. Stockpiles, steep cuts, and fill slopes are to be covered or protected with mulch, sod,
plastic covering, jute matting, etc. if unworked for more than 12 hours.
3. Cover materials (plastic, matting, etc.) sufficient to cover all disturbed areas, shall be
stockpiled and available onsite.
4. All areas that are to be unworked during the wet season shall be seeded within one
week of the beginning of the wet season.
5. Mulch is required to protect all seeded areas.
6. Fifty lineal feet of silt fence, with posts, per disturbed acre must be stockpiled onsite. 8
acres = 400 lineal feet required.
7. Properly installed silt fence is mandatory along the downslope of all disturbed areas of
the site. Perimeter protection filters runoff and reduces the amount of sediment that may
leave site.
8. Construction road and parking lot stabilization are required for all sites.
9. Sediment retention is required unless no offsite discharge is anticipated for the specific
design flow.
10. Surface water controls are required unless no offsite discharge is anticipated for the
specific design flow.
11. Phasing and more conservative BMP’s must be evaluated for construction activity near
surface waters.
12. Any runoff generated by dewatering may be required to discharge to the sanitary sewer
(with appropriate authorization), portable sand filters systems, and holding tanks.
13. The frequency of maintenance review should increase from weekly to daily where
warranted.
Project specific provisions instituted by Goodfellow Bros:
1. Non-paved roadways, alleys, and laydown areas to be stabilized with 4” minimum
thickness 1-1/4” aggregate. Fill slopes and stockpiles to be plastic covered (BMP C123).
All other areas to be surface roughened and hydroseeded (BMP C120).
2. Surface water to be conveyed via rock lined ditches with check dams (BMP C200).
Steep slopes to have 8” pipe slope drains to transfer water from bench swale to rock
lined ditch (BMP C204).
3. All surface water to be directed to the south vault for storage and treatment. Water will
be pumped from the vault through a Watertectonics 300-gpm electrocoagulation (non-
chemical) treatment unit and sand filters before testing and discharge.
It is anticipated that all turbid water in the work areas will be captured and treated,
however, should water leave the work area, turbidity is not to exceed 25 ntu. Run-off
from the site that reaches receiving water shall not increase turbidity of the receiving
water by more than 5 ntu. Monitoring will occur weekly and after rain events. Water
quality readings at the sample location as well as regular CESCL inspections will dictate
the need for additional actions and maintenance.
4. For any work during the wet season, excavated soils shall be direct loaded into dump
trucks for off-haul or stockpile. Plastic will be kept onsite to cover stockpiles if unworked
for more than 12-hours. Area of active work will be restricted in size and any area that is
excavated will be backfilled and stabilized daily. No work will take place during a “rain
event”.
All mass excavation and grading activities will be completed or paused prior to
September 30th in accordance with Hearing Examiner Condition 1 a. “Clearing and
grading of the subject property shall be limited to May 1 to September 30.”
5. Stabilize disturbed areas immediately after completion of work or in anticipation of a rain
event.
6. Street sweeping shall be performed regularly and during off-haul activities.
Activities scheduled to be performed during this period include the installation of CCUD sewer
mainline as well as City of Renton storm drain mainline including stormwater vault construction.
Installation of water mainline for both CCUD and City of Renton is additional work to be
completed.
Ongoing inspection of Appendix D requirements as well as the Project specific provisions will be
performed by both the Project CESCL and Goodfellow Representative to ensure the above
activities can take place while successfully maintaining a stabilized site.
Project CESCL:
Jessie Gilbert – Earth Solutions NW
ECO-3-6132204
(206) 468-0991
Goodfellow Representative:
Kyle Williams
EF8183376
(253) 293-4993
Canopy - Stromwater Detention/Treatment Plan
Wet Weather Plan 2022/23
Work Area
6.5 Acres - Disturbed 283,140 sf
1.1 Acres - Gravel 47,920 sf
Estimated Contribution Area 331,060 sf
10-yr 24-hr event volume 449,590 gallons
(sf x run-off CN(.74) x 2.95" storm depth x 7.48 gal/cf)
Design Storm Event Requirement 674,380 gallons
(10-yr volume x 1.5, per BMP C250/251)
Detention Treatment Requirement
qty gpm/system
Electrocoagulation Treatment Rate 1 300
Treatment Volume 8 Hours/day 144,000 gallons
South Vault 613,960 gallons
Detention/Treatment Provided 757,960 gallons
Detention/Treatment provide greater than the Design Strom Evenet Requirement Volume
ALLEY 1
ROAD ALINCOLN AVE NE
VAULT ACCESS RD
TR. K
TR. J
TRACT G
TRACT HTRACT A
9
8
7
10
16
15
14131211
2
4
1
5 63
TRACT D
NORTH VAULT ACCESS RD.VAULTACCESS AIN COMPLIANCE WITH CITY OF RENTON STANDARDS
DESIGN
12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877
CIVIL ENGINEERING
LANDSCAPE ARCHITECTURE
PLANNING
SURVEYING
CANOPY CANOPYCANOPY4196 LINCOLN AVE NE, RENTON, WA 98056 C: 21000838LUA: 19-000223PR: 19-000387SEE SHEET C3.02
KEY MAP
LINCOLN NE 40TH STAVENE
GRADING PLAN C3.01SEE SHEET C3.04C3.01LEGEND
SOIL AMENDMENTTED-40-4179R-417920
Plastic cover fill slopes
Plastic cover fill slopes
DEVELOPMENT ENGINEERING
msippo 05/10/2022
Storm water conveyance ditch rock lined
Down slope pipe drain 8"
Inlet protection
Sediment Trap
Straw Wattle
Storm Water weir tanks
Water treatment Electrocoagulation
Sand Filter
Generator
Permanent Pipe Used for Temp Conveyance
Discharge Piping
Plastic sheeting
Hydroseed
Aggregate Surfacing
Discharge Testing
Point
Construction Entrance
ROAD A
ALLEY 2
ALLEY 3
TRACT C
TRACT F
45 44
43
42 41
50 5352 54
49
48
5551
46
47
TRACT BALLEY 2A IN COMPLIANCE WITH CITY OF RENTON STANDARDS
DESIGN
12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877
CIVIL ENGINEERING
LANDSCAPE ARCHITECTURE
PLANNING
SURVEYING
CANOPY CANOPYCANOPY4196 LINCOLN AVE NE, RENTON, WA 98056 C: 21000838LUA: 19-000223PR: 19-000387SEE SHEET C3.01
KEY MAP
LINCOLN NE 40TH STAVENE
GRADING PLAN
C3.02SEE SHEET C3.03C3.02LEGENDSOIL AMENDMENTTED-40-4179R-417921
Plastic cover fill slopes
DEVELOPMENT ENGINEERING
msippo 05/10/2022
Storm water conveyance ditch rock lined
Down slope pipe drain 8"
Inlet protection
Sediment Trap
Straw Wattle
Permanent Pipe Used for Temp Conveyance
Plastic Sheeting
Hydroseed
Aggregate Surfacing
ALLEY 3
ROAD A
NE 40TH STTRACT F
TRACT C
40
30
22 23 24
17
25
18
26
19 20
27
21
28 29
3435
31
39
32
373737 3638
33
TRACT G IN COMPLIANCE WITH CITY OF RENTON STANDARDS
DESIGN
12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877
CIVIL ENGINEERING
LANDSCAPE ARCHITECTURE
PLANNING
SURVEYING
CANOPY CANOPYCANOPY4196 LINCOLN AVE NE, RENTON, WA 98056 C: 21000838LUA: 19-000223PR: 19-000387SEE SHEET C3.04
KEY MAP
LINCOLN NE 40TH STAVENE
GRADING PLAN
C3.03SEE SHEET C3.02C3.03LEGENDSOIL AMENDMENTTED-40-4179R-417922
Topsoil Stockpile - Track walk and Plastic Cover
Plastic cover fill slopes
Storm water conveyance ditch rock lined
Down slope pipe drain 8"
Inlet protection
Sediment Trap
Straw Wattle
Permanent Pipe Used for Temp Conveyance
Plastic Sheeting
Hydroseed
Aggregate Surfacing
DEVELOPMENT ENGINEERING
msippo 05/10/2022
Gravel Laydown/Staging Area
NE 40TH STLINCOL
N
A
V
E
N
E
TRACT G
IN COMPLIANCE WITH CITY OF RENTON STANDARDS
DESIGN
12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877
CIVIL ENGINEERING
LANDSCAPE ARCHITECTURE
PLANNING
SURVEYING
CANOPY CANOPYCANOPY4196 LINCOLN AVE NE, RENTON, WA 98056 C: 21000838LUA: 19-000223PR: 19-000387KEY MAP
LINCOLN NE 40TH STAVENE
GRADING PLAN C3.04SEE SHEET C3.01SEE SHEET C3.03
LEGENDC3.04SOIL AMENDMENTTED-40-4179R-417923
DEVELOPMENT ENGINEERING
msippo 05/10/2022