SW_Review_Comments.pdf
City of Edmonds
TH
121 5 AVENUE NORTH
EDMONDS, WA 98020
(425) 771-0220
FAX(425) 771-0221
Website: www.ci.edmonds.wa.us
DEVELOPMENT SERVICES DEPARTMENT
Planning Building Engineering
Stormwater Review Comments
Permit : Date:
# BLD20061302 10/05/2007
Project Name/Address:
Emerson SFR/7211 Meadowdale Beach Road
Contact Person/Address/Fax:
Larry E. Steward, PE/24738 SE Mirrormont Drive,
__
Issaquah, WA 98027/Email lesteward@hotmail.com/Fax /Fax (425) 392-6111
Reviewer: Division: Engineering
Blaine Chesterfield
During review of the subject submittal it was found that the following information,
corrections, or clarifications will need to be addressed:
1.
The rain fall distribution per the City of Edmonds codes is 2-yr, 24-hr storm --
-- 1.5 inches; 10-yr, 24-hr storm ---- 2.0 inches; and 100-yr, 24-hr storm ----
3.0 inches. The Storm Drainage Report used 1.75 for the 2-yr storm, 2.25
inches for the 10-yr storm and 3.5 inches for the 100-yr storm. The analysis
can continue to use those rainfall totals, the intent is to make you aware that
you exceeded the Citys requirements regarding the rainfall data.
2.
For the existing conditions the time of concentration (Tc) is 6.3 minutes. 6.3
minutes is the minimum and needs to be higher for the existing conditions.
Please take a second look at the existing conditions Tc and adjust up to a more
appropriate level.
3.
For the proposed conditions a curve number (CN) of 86 should be used for
any areas that will be lawn.
Please resubmit three copies of the revised plans/documents to a Development
Services Coordinator. You may contact me at 425-771-0220 if you have specific
questions regarding these plan corrections.