Talbot Rd 17808-White -Drainage review comments.pdf
DATE: February 4, 2009
TO: File
FROM: Jerry Shuster, P.E., Stormwater Engineering Program Manager
RE: Application #: BLD20090043
Project: White Property
Project Address: 17808 Talbot Rd.
During review of the above noted application, it was found that the following information,
corrections, or clarifications are needed.
Items reviewed:
Limited Subsurface Exploration and Geotechnical Report, White Residence Remodel,
·
Associated Earth Sciences, Inc. dated January 14.2009
Drainage Calculations for WESCO Group, 17808 Talbot Rd., Prepared by HN Lehtinen
·
Engineering, dated December 19. 2008
Site Plan 17808 Talbot Rd., prepared by WESCO Group, received by the City of
·
Edmonds, January 20, 2009.
The Limited Subsurface Exploration and Geotechnical Report is primarily contains geotechnical
information to facilitate the design the proposed building foundations. The one paragraph on
page 9 that discusses site drainage does not contain he information necessary to assess the
feasibility of an on-site infiltration system. A draft handout is enclosed in this review
(Attachment A) that explains the requirements. Basically, a perc test or soil grain size analysis is
required to assess the feasibility of an on-site infiltration system.
The paragraph that also dicusses site drainage refers to a creek that borders the property. This
creek is not shown n the Site Plan. There may be buffer issues depending on type of creek and
proximity to structures. Also, the copy of the Limited Subsurface Exploration and Geotechnical
Report I received was missing Figures 1 and 2.
The Drainage Calculations document is extremely brief and difficult to follow. Page 1 refers to
volumes from selected storm events and says From computer output. No computer output was
found in the copy of this report I received. Please refer to the handout referred to in the
proceeding paragraph for guidance on design of an infiltration system. Using infiltration rates
from publications is not acceptable.
Site Plan The infiltration system shown on this drawing should be re-sized if it shown to be
feasible based on the attached handout.
Please contact me at 425-771-0220 or by e-mail at mcconnell@ci.edmonds.wa.us if you have
specific questions regarding these plan corrections.
Talbot Rd 17808-White -Drainage review comments
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