HomeMy WebLinkAboutMAPLE HILL, PHASE ONE - PDP - 29-00A - SUBMITTAL DOCUMENTS - ROUND 1 - VARIANCE REQUESTY
January 28, 2003
Mr. Dave Stringer
City of Fort Collins
Engineering Department
281 N. College Ave.
PO Box 580
Fort Collins, CO 80522-0580
Re: Maple Hill Storm Sewer cover variance request
Project No.: 0953-003
Dear Dave,
This letter is regarding the Maple Hill storm sewer minimum cover variance request.
Due to site constraints associated with the existing Larimer/Weld No.8 irrigation outlet
elevation, the proposed 100-year discharge and existing topographic elevations for the
development, the proposed Maple Hill project has one area of storm sewer that does not
meet the minimum cover criteria of the LCUASS manual. Storm sewer line ST5 and 5B
(intersection of Maple Hill Drive and Thoreau Drive) have between. 1.00-1.88 feet of
cover, instead of the recommended 2.0 feet as stated in Section 12.2.2 of the LCUASS
manual, this is a 0.12-1.00-foot difference. Per our conversation with you on January 8,
2003, it was stated that the installation of a stabilization fabric (geo fabric), per the City of
Fort Collins Construction Standards, would be supported and approved by the City of
Fort Collins Engineering Department. This stabilization fabric will be installed within the
intersection of Maple Hill Drive and Thoreau Drive to mitigate vibration degrigation of the
street base course and asphalt.
The stabilization fabric will be installed by the developer and will not result in any
additional capital or maintenance costs to the city. The installed fabric will not create
any safety, welfare or public health issues, nor will it reduce the design life of the public
streets. The allowance of the variance will create a better design of all storm sewer and
drainage facilities, resulting in reduced negative affects created by storm generated
runoff.
We appreciate you review and approval of said variance. If you have any questions or
concerns, please feel free to give our office a call.
t— x
KGS/sjk
TST, INC. 748 Whalers Way - Building D
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