bld20141182_OldWoodway-playfields-1.docx
City of Edmonds
TH
121 5 AVENUE NORTH • EDMONDS, WA 98020 • (425) 771-0220 FAX(425) 771-0221
Website: www.edmondswa.gov
PUBLIC WORKS DEPARTMENT
Engineering Division
Plan Review Corrections
Plan Check : Date:
# BLD20141182 December 19, 2014
Project Name/Address:
Edmonds School District 15 Old Woodway Playfields 23200 100th Ave W
Contact Person/Address/Fax:
Matt Finch finchm@edmonds.wednet.edu
Reviewer: JoAnne ZulaufDivision:Engineering
During review of the subject submittal, it was found that the following information, corrections, or
clarifications would need to be addressed. All Handouts and Standard Details referred to in these
comments can be accessed at our website: www.edmondswa.gov by choosing Permit Assistance:
1. Please add note to erosion sediment control plan sheets F-0.2 and F0.2A regarding the wet
weather “work surface” requirement described on pg 11 of the Associated report.
2. Please add notes to demo and grading plan sheets stating that Special Inspections by the
geotech of record are required for determining suitable subgrade and structural fill per the
Associated report.
3. Add note to drainage plans regarding the requirement of Special Inspection for drainage
aggregate testing as stated in the Associated report.
4. Attached is a Special Inspection report agreement. Please complete and return prior to
permit issuance.
5. CB#5, shown on sheet F1.2, appears to be located exactly where the phase 3 Field
House/Concessions building will be constructed. Please revise location keeping in mind
that the future building downspouts will need to connect to the storm system.
6. On sheet F1-3, please determine the outlet connection at the sw corner of the field and add
to plans.
Stormwater Engineer comments:
Jerry.Shuster@edmondswa.gov
425-771-0220 x1323
Stormwater Site Plan
Section 4, page 4 – all the minimum requirements should apply to the converted pervious surfaces as shown in
the figure. The ESCS Table 4-4 has a typo. Disturbed pervious surfaces should have compost-amended soils (as
described on page 6, minimum requirement #5)
Section 4, page 5 – Minimum Requirement #2 – The proposed project disturbs over 1 acre. A Construction
Stormwater General Permit form the Dept. of Ecology is required. Please provide the Notice of Intent (NOI) for
this permit.
DATE FAXED/E-MAILED 7/2/2017 PAGE ___ OF __
12
Section 4, page 6– Minimum Requirement #8 –The City acknowledges that under the 2005 Ecology Stormwater
Management Manual for Western Washington (SWMMWW) turf fields such as the ones proposed for this
project are not called out as pollution generating impervious surfaces (PGIS). As you know, the 2012 version of
the SWMMWW does classify synthetic turf fields as PGIS. While the science to support this unclear, the City
does have potential liability from zinc-containing runoff entering its stormwater system. Especially in this
particular situation where the discharge from the City’s stormwater system will discharge into Deer Creek, a
drinking water source for Olympic View Water & Sewer District. Under these circumstances the City will require
treatment of the discharge from the proposed field prior to discharging to the City’s stormwater system.
Section 3.4 , Volume V of the 2005 SWMMWW, provides a menu of treatment option for dissolved metals. As
you point out in your November 12, 2014 memorandum (from Nichole Hernandez, PE to Jerry Shuster PE), a
basic sand filter vault followed by a media filter will meet the 2005 SWMMWW requirements. The City would
approve a system that just has a sand filter vault without the media filter. It would provide us with some degree
of liability coverage without burdening the project with excessive capital or on-going maintenance costs.
Plan Sheets
Sheet F-1.1 and F-1.3 – Does the underdrain system capture rainfall that infiltrates through the rubberized
track? It’s hard to tell from the drawings, although it has been included in the modeling calculations.
Sheet F-1.3 – There is new piping and catch basins proposed for the areas southeast and southwest of the
proposed fields. Where to these areas discharge to and how were they accounted for in the modeling? Is this
part of the bypass?
Sheet F-2.1, Detail 4, Seeded Site Soil Restoration – Replace the note for “… planting soil” with compost-
amended soil per Ecology BMP T5.13.
Sheet F-2.1, Details 5 and 8, Rubberized surface section and Pervious Concrete Paving – The subgrade should
NOT be compacted under porous asphalt or previous concrete. Also, provide a callout for the type of rock that
will be used in the permeable aggregate base. What is the porosity of the rubberized surfacing?
Sheet F-2.2, Detail 4, Flow Control Structure (FCS) – The City no longer accepts shear gates. Please use City
standard detail E5.4 for a the FCS (.dwg file available at: http://www.edmondswa.gov/services/permits-
development/handouts-forms/services-permits-std-details-main-page-menu/services-std-details-storm-
drainage-section-5-menu.html ). Note that the v-notch weir on top of the rise in the detail is not
required. Change as needed.
Also in in Detail 4, the modeling uses a riser height of 3.55 feet. Detail 4 has 3.45 feet between the outlet invert
and the riser top. Please reconcile.
Jerry Shuster, P.E.
Stormwater Engineering Program Manager
Jerry.Shuster@edmondswa.gov
425-771-0220 x1323
Please resubmit 3 copies of the revised plans/documents and written responses to each comment to a
Development Services Coordinator. Please contact me at 425-771-0220 if you have specific questions
regarding these plan corrections.
DATE FAXED/E-MAILED 7/2/2017 PAGE ___ OF __
22