04-0180 Eng Review No 2 042405
City of Yelm
Community Development Department
105 Yelm Avenue West
P.O. Box 479
Yelm, WA 98597
April 24, 2005
Bob Tauscher
Jerome W. Morrissette and Assoc.
1700 Cooper Point Road SW #B2
Olympia, Washington 98502
RE: Ridgeline Middle School - SPR-04-0180-YL
Second Review of Civil – Site Construction Documents
Mr. Tauscher:
The City of Yelm has completed the second review of the proposed junior high school referred to as Ridgeline Middle School. Your application included:
Civil Engineering Plans dated 4/4/2005
We have reviewed the plans for compliance with the City of Yelm Development Guidelines, the DOE Stormwater Manual and general standards of civil engineering practice. The following
comments need to be addressed before the plans may be approved for construction. The plans have been reviewed as submitted. If you have made any changes to the plans since the initial
submittal they should be shown the revised plans. Our comments are summarized below:
Site Plan (sheet C1.2):
The parking stalls do not meet the City of Yelm standards. Please review city details and revise as necessary.
STEP Plan (sheets C3.1, 3.4, 3.5, 3.7):
A hose bib will be required within 40’ of this STEP tank for maintenance. The callout for the hose bib is connecting it to the irrigation system. This hose bib will need to be connected
to a “constant on” water source.
Please add a callout to the civil plans with the size of the grease interceptor.
The sewer mainline connecting at the existing main and running to the step tank needs to be run parallel and at least 10’ horizontally from the proposed sewer main.
The step tank invert should not be deeper than six feet from invert to finished grade.
Water Plan (sheets C3.0, 3.2, 3.3):
The water meter will be required to be a compound meter meeting City standards. Following a discussion between Bob Tauscher and myself it was the school’s preference to have a bypass
installed in the vault. This has been shown on the plans however the bypass meter is not shown. Please add the second meter to the detail.
A Reduced Pressure Backflow Assembly will be required after the water meter. This must be installed immediately after the water meter. No exceptions can be made.
A double check valve will be required after the irrigation meter. Please call out the need for the DDCV on the civil plans. The specifications may be located on the landscape plans.
Water usage calculations have been submitted and are being reviewed.
Stormwater Report:
The proposed Vortechnics stormwater treatment system will be allowed if the following provisions can be met per the DOE General Use Designation:
The sizing of the vault is in compliance with the Department of Ecology’s Use Designation which specifies 35 gpm/sf using the Western Washington Hydrology Model (WWHM). When using the
SBUH or SCS methods the accepted standard is 15 gpm/sf.
It is recommended that the Vortechnics is installed following a flow splitter. This splitter should be designed with stand pipes, separating the 6 month flows from the 100 year flows.
Please show the stand pipes within the catch basin.
The landscaping plans are still being reviewed and a letter will be issued.
Please note that all conditions of land use approval must be met prior to building permit issuance, including condition #4 and #17.
Please review and revise the plans to address the above referenced comments. When the project is resubmitted you will need to submit 4 sets of plans, 2 stormwater reports. The project
engineer should include a written response with the resubmittal, indicating how all the review comments above have been addressed or responded to. This will significantly expedite our
review of the project. If you have any additional questions or comments please do not hesitate to call or contact me at jimg@ci.yelm.wa.us.
Community Development Department
Respectfully,
Jim Gibson
Development Review Engineer
Cc Grant Beck, Tami Merriman, Gary Carlson, City of Yelm
Rocky Birkland, Yelm Schools
enc. Redlined Landscape Plans