8345 civil no 1July 1, 2003
Bob Tauscher
JWM & A
1700 Cooper Point Road SW #B2
Olympia, WA 98502-1110
RE: Yelm Middle School Parking Lot
Civil Engineering Review No. 1
Yelm Project Civ-03-8345-YL
Dear Mr. Tauscher:
The following are comments or concerns with the above referenced project. When resubmitting the plans resubmit 4 sets and 2 drainage reports.
The stormwater calculations do not appear to match the plan submitted with them. The infiltration gallery size does not reflect the submitted calculations.
My calculations show that the stormwater basin size contributing to the new stormwater system should be 6,669 square feet or 0.153 acres. This number is from the following numbers shown
on the plan:
New sidewalk area 2,316 sf
Old sidewalk area to asphalt 2,049 sf
Grass to new asphalt area 2,304 sf
When using the DDECM table 4.1, the table shows the minimum required amount of volume for the gallery. Please revise the calculations.
The gallery size in not consistent with the calculations. I am not sure what size gallery is being proposed. Please review and revise the gallery to be consistent.
The method of stormwater treatment chosen for this parking lot has not been approved for use in the City of Yelm. Please revise or contact me for further information.
The parking lot layout appears to meet the City of Yelm Development Guidelines as proposed.
Please see attached landscape comments. You will need to submit a landscape plan showing the improvements. This plan can be on the same sheets as the grading and storm drainage plan.
If you have any additional question please do not hesitate to call me at 360-458-8438.
Respectfully,
Community Development Department
James Gibson
Development Review Engineer
Cc