20081208162150.pdfNovember 25, 2008
Mr. Jerry Shuster
Engineering Department
City of Edmonds
121 5`" Avenue, North
Edmonds, WAS 98020
NOV (5 2008
RE: Columbia Rim Warehouse
Proposed Revisions to Storm Drainage
Permit #2007-0684
Dear Mr. Shuster:
The purpose of this letter is to document the proposed field changes to the Columbia Rim
Warehouse construction plans and to certify that these changes will not result in any
negative perfbrmance. We are proposing two changes to the approved construction
plans.
The 2-60" x 71' long detention pipes and the 3-36" connector pipes, located on the ends
of the detention pipes, would be changed to HDPE pipes. The proposed detention pipes
and the connector pipes all meet the minimum cover requirements for HDPE pipes (2,
minimum cover) and shall be constructed in the field to this standard.
The contractor would additionally hike to change the sizes of the 3-36" connecter pipes to
24" pipes, for ease of construction with the 2-48" and 2-54" catchbasins. The inverts will
remain per plan for construction. The 36" connector pipes were not designed for
detention storage area, so the detention storage volume of the detention system will
remain as approved.
Per our phone conversation, we understand that these changes are permitted, and we will
proceed with these changes,
20021 1201h Ave NE Tel (425) 415 6144 www.esmciviLcom J 1" I [I ft j I
Suite 103 Fax (425) 416 0924
Bothell, WA 90011 Tok Free 0661 615 6144 and it v iiI insd " �-I AI'
Mr. Jerry Shuster
November 25, 2008
Page 2
Please do not hesitate to contact me if you have any additional questions or require any
additional information,
Sincerely,
ESM CONSULTING ENGINEERS, LLC.
KRISTAL GREENHAW, P.E.
Associate
mu$TIT,rs. I W.- my
44esm4lengr4esmjobM1324001 QMdocumentletter-004,doc