BLD20151302-Jimenez_ENG2.docx
CITY OF EDMONDS
PLAN REVIEW COMMENTS
ENGINEERING DIVISION
(425) 771-0220
City Website: www.edmondswa.gov
DATE: March 22, 2016
TO: Kristin Hanson
hansondesign@hotmail.com
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FROM: Jennifer Lambert-JoAnne Zulauf (2 review)
Engineering Technician
RE: Application #: BLD20151302
Project: Jimenez - Addition
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Project Address: 7520 – 215 St SW
During review of the above noted application, it was found that the following information, corrections, or
clarifications are needed. Reviews by other divisions, such as Planning and Building, may result in
additional comments. Please redline plans or submit three (3) sets of revised plans/documents with a
written response to each of the items below to a permit coordinator.
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Resubmittals can be made at the Development Services Department on the 2 floor of City Hall. Permit
Center hours are M, T, Th & F from 8am-4:30pm. The Permit Center is closed on Wednesdays.
City of Edmonds handouts, standard details and development code can be referenced on the City website.
Please Note: Building Handouts do not include updated Engineering Division Requirements. Refer to
Engineering Handouts for all Engineering Requirements.
1)
Based on City documents, it appears that the gravel area adjacent to the driveway was added after
1977. Therefore, this area shall be included in the impervious surface calculations.
a.
Per the numbers provided, the gravel area and the proposed addition creates more than
2000sqft of impervious area constructed after 1977.
i.
Show the required stormwater mitigation system designed as directed per the
Edmonds Community Development Code (18.30) and the Stormwater Supplement.
Please refer to the #E72 City handouts for additional information.
ii.
Or, remove impervious area; such that the impervious surface area added after 1977
does not exceed 2000sqft.
2)
It appears that the gravel area extends to the roadway. Please revise the plans and the impervious
surface calculations to include this area.
3)
No credit is given for impervious area that is removed. Please remove the 500 sqft credit notation
shown.
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4)
Please note what type of deck (i.e. spaced deck with permeable surface below, deck with
impervious surface below, impervious deck, etc.) so that it can be determined if the deck shall be
included in the impervious surface calculations. If the deck is impervious or an impervious
surface is being added below the deck, please revise the impervious surface calculations
accordingly.
5)
A cleanout is required on the side sewer within 2’ of the structure. If a cleanout will need to be
added (due to the addition), please note as such on the plans.
6)
Please show temporary erosion control measures and reference the appropriate City Standard
Details.
Response to Submittal of New Drainage Report and Plans
1. Site plan does not reflect the information shown on the civils, please provide plans that are
consistent.
2. A Low Impact Development Covenant is required when using dispersion for stormwater
mitigation. Please find the covenant attached. The covenant exhibit should show clearly all the
dispersion areas of vegetation and soils amending to be retained as part of the overall mitigation for
this project.
Stormwater Engineer Consultant Review Comments:
After reviewing the stormwater report and plans for the improvements proposed for 7520 215th St. SW
(Jimenez Single Family House), we have the following comments:
Targeted Drainage Report for Jimenez Single Family House (1/29/16)
1.If splashblocks are used for downspout dispersion, the minimum vegetated flowpath is 50’, not
25’. Options for a 25’ flowpath include perforated stub-out connections or a gravel-filled
dispersion trench.
2.Drainage Report (1/29/16) lists 2,885 sf on the site classification report and the Driveway and
Drainage Plan (1/29/16) lists 2,855 sf.
3.The Drainage Report lists BMP T5.12 (Sheet Flow Dispersion) as one of the project BMPs;
however, this is not shown on the Driveway and Drainage Plan. The minimum vegetated flowpath
for sheet flow dispersion would be 50’.
Driveway and Drainage Plan (1/29/16)
1.The Post Construction Amended Soil Placement Exhibit lists “Area of post construction imported
topsoil placement per BMP T5.13 in order to achieve full dispersion per BMPT5.30” is not a true
statement. The design would have to retain 65% of the site in a forested condition to achieve full
dispersion.
2.The Post Construction Soil Quality and Depth notes list four options for compost-amending soils;
however, the City’s handout (E72-C) only lists two options:
a.Compost-amending existing soils
b.Importing a topsoil/compost mix
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The following should also be included in the information conveyed to the applicant, but does not require
substantial revisions to the submittal:
Minimum requirement #3 – Source Control is not required for single family residential projects.
The statement “However, the LID flow dispersion into a vegetated area, via a transition zone from
the paved driveways, provides source control” is not a true statement since dispersion is not
considered to be a source control BMP.
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