05-0058 Civil Review 2 013006
City of Yelm
Community Development Department
105 Yelm Avenue West
P.O. Box 479
Yelm, WA 98597
January 30, 2006
Robert Holcomb
KPFF Engineering
4200 6th Ave Suite 301
Lacey, Washington 98503
RE: Green Village Subdivision –SUB–05-0058-YL
Initial Review of Site Construction Documents
Mr. Holcomb:
The City of Yelm has completed the initial review of the proposed 52 lot single family subdivision. Your application included:
Construction documents dated 10/12/05 received 10/13/05.
Stormwater Drainage Report October 2005 received 10/13/05
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. Our comments are summarized below:
Cover Sheet and Plat Map (sheets C2):
The locations of the mailboxes can not be located in the cul-de-sac planter islands. They must be located between the sidewalks and curb so the pedestrians can have access to the mail
boxes from the sidewalk. Please revise the locations to be adjacent to the current locations. Please note the post offices requirements on the original approval.
Roadway Plan and Profile (sheet C3):
Revise the driveway apron at the entrance to the community center it should be a type 1 approach.
After much deliberation and research you can remove the bypass designs from the stormwater systems. Current stormwater methodology is to allow all water to be routed through the wet
tank treatment before the infiltration galleries.
The stormwater conveyance system needs to be located in the right of way or in
easements that will not be buildable. See redlined plans for areas.
Water Plan (sheet C8):
The fire flow calculations should show what the fire flow is going to be at the fire hydrants. They may be easily done by revising the information submitted.
All meters should be shown in the planter strip not behind the sidewalk including in the cul-de-sacs.
The air vac release exit pipe needs to come out side of box not thru lid. Please revise the detail to show this.
Water meter boxes in driveways need to be traffic bearing. Call out the meter box to be load bearing in design not the meter.
STEP Plan (sheet C9):
Gate valves are required to be installed at Sta. 4+50 and 9+50 in the subdivision. Show on the plan.
Show step tank location for the Community Building. This should be shown to make sure the connection can be made without conflicting with the water and storm systems.
Grading Details (sheet 10):
Use City of Yelm standard detail for roadway sections. Add these details to the plans.
The elevations shown on the infiltration galleries are approximately 17 feet below the finish grade at the property line. (lot no. 11) You will be required to have substantial shoring
to install this design without affecting the adjacent properties. If you chose to continue with this design please show detailed information on the plans and how the installation will
be performed without affecting the adjacent properties or the fence line.
Same comment as No. 10 for the wet tank installation.
Stormwater Report:
The report only shows that you are routing the 10-year storm in basin A. The 100-year needs to be routed.
The stormwater manual caps the infiltration rate at 20 in/hr. You have shown the infiltration rate at approximately 36 in/hr. Please revise the rate to be no more than 20 in/hr maximum.
Landscape and Irrigation Plan:
The required landscape and irrigation plan was not submitted as part of this package. The construction plans will not be approved until landscape and irrigation plans have been approved.
Please coordinate with Tami Merriman at (360) 458-8496.
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 is required to 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 P.E.
Development Review Engineer
cc.
enc. Redlined plans