bld20140871-Harter-ADU.pdf
CITY OF EDMONDS
PLAN REVIEW COMMENTS
ENGINEERING DIVISION
(425) 771-0220
City Website: www.edmondswa.gov
DATE:September 24, 2014
TO:Riverside Architecture
Jeff Price
jeff@riverarch.net
FROM:Jeanie McConnell
Engineering Program Manager
RE:Plan Check #:BLD20140871
th
Project& Address :Harter –9630–238St SW
During review of the above noted application, it was found that the following information,
corrections, or clarifications are needed. 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.
City of Edmonds handouts and standard details can be referenced on the City website under Permit
Assistance.
1)Please show all utility information on one plan, preferably the site grading and drainage plan.
Information related to the gas meter and the side sewer appears to be complete on the site plan
only.Other utility related information has been noted in the comments below. Please address
these comments on the site grading, drainage and utility plan.
Please provide the impervious surface calculations as shown on the plans in the table format
2)
provided below.
IMPERVIOUS SURFACE CHART
LineTypeArea (square feet)
1.Non-Regulated
ExemptRegulated
2.Replaced
3.New (Post 1977)+
Total Regulated ImperviousArea
4.=
Mitigation required if in excess of 2000sf
-
5.Total Area Mitigated by Existing Stormwater Management System(s)
6.Regulated Area Not Yet Mitigated=
7.Area Proposed to be Mitigated by Low Impact Development Techniques=
8.Area Proposed to be Mitigated through Conventional SWM Techniques=
3)Show location of the existing water service line from the meter to the house.
4)The proposed improvements appear to create more than 2000 square feet of new impervious
surface area. City stormwater regulations went into effect in 1977. Per Edmonds Community
Development Code 18.30, sites that create 2000sf or more impervious surface area from 1977
forward shall provide stormwater management. Please refer to the City’s stormwater handouts
(E72 series)found in the Stormwater Managementsection on the City website.
a.Low impact development techniques are encouraged to be used whenever feasible.
b.Stormwater management systems designed for impervious surface areas greater than
5000sf shall be designed by a licensed engineer.
c.Two downspout infiltration systems have been shown on the plans, but design
calculations, including infiltration pit test information,hasnotbeen provided to support
the sizing.
d.Indicate on the plans how on site impervious surface areas will be collected and
discharged to the stormwater management system(s).
5)Clearly show/label impervious surface areas and proposed materials on the drainage plan.
a.Label the driveway surface material. The site plan indicates asphalt, however the
drainage plan hatching is typical of concrete. If concrete is the desired surface material,
it will need to stop at the property line and transition to asphalt for that portion located
within the City right-of-way.
b.Will there be a walkway connection between the new driveway and the ADU entry?
c.Label the deck on the drainage plan and note as pervious or impervious.
6)As the proposed retaining wall supportsa surcharge,thedesign and calculations will need to be
prepared by a licensed engineer and submitted to the City.
7)The wall drain outlets are shownboth in the right-of-way and on private property at or near
property lines and slopingtoward adjacent properties. Stormwater runoff shall be managed on
site and not directed to a neighboring parcel. Please revise plans as needed.
8)It appears as though theexistingCATV locationmay be in conflict with the proposed addition.
Please indicate rerouting as needed.
Please contact me at 425-771-0220 or by e-mail atJeanie.mcconnell@edmondswa.govif you have
specific questions regarding these plan corrections.
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