HomeMy WebLinkAboutCHICK-FIL-A, MINOR AMENDMENT - MA0900004 - CORRESPONDENCE - DRAINAGE REPORTThe undisturbed portion of the site (1,461 square feet or 10% of the site) includes the existing slope and
banks of the No. 2 Canal which will retain its historic flow patterns. Upon completion, the proposed site
will consist of 10,360 square feet impervious area, or approximately 70.5% of the site. The total net
impervious area of our site will be increased by approximately 160 square feet or 0.5% to a total site
imperviousness of 70.5%.
In summary, the proposed Chick-fil-A development will improve the existing drainage patterns of the site
by providing area inlets and water quality. The site's imperviousness area will increase by approximately
160 square feet or 0.5%. The existing Latimer County No. 2 Canal will be minimally affected by the
construction of the proposed storm outfall, and erosion control methods will be implemented on the site to
protect the Canal as well as reduce sedimentation of the site.
Thank you for your time regarding this matter
Very truly yours,
MERRICK & COMPANY
Todd Hepworth
Project Engineer
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❑❑❑ BUILDING QUALITY SOLUTIONS
Merrick & Company
2450 S. Peoria Street
Aurora, CO 80014.5475
Phone: 303-751.0741 / Fax: 303-751-2581
www.merrick.com
March 9, 2009
Merrick Proj. #03015950
Mr. Glen Schlueter
City of Fort Collins
281 North College Ave.
Fort Collins, CO 80522-0580
RE: Chick-fil-A at the Cottonwood Shopping Center — Commercial Drainage
Dear Mr. Schlueter:
The intent of this letter is to address drainage patterns with regard to the proposed Chick-fil-A
development at the Cottonwood Shopping Center located at the southwest corner of Horsetooth Rd. and
College Ave. The site is located in Lot 1, Block 1 replat of Lots 1, 2, 3, and 4 of the Cregger Plaza
Subdivision, northeast quarter of Section 35, Township 7 North, Range 69 West of the 6 ' Principal
Meridian in the city of Fort Collins, Colorado. The Chick-fil-A site consists of 14,701 square feet or 0.34
acres.
Currently, the existing site is occupied by a vacant restaurant building with outdoor seating patios,
sidewalks, landscaping and utilities. The ground is characterized as developed landscaping and irrigated
short grasses. The existing Larimer County No. 2 Canal also flows on the site along the northeastern
edge. Existing drainage patterns consist of overland sheet flows east and south either directly into the
existing canal or traveling offsite over the existing adjoining parking/drive areas within the shopping
center and into the Canal via a concrete Swale located southeast of the site. The existing imperviousness
of the site is roughly 10,200 square feet, or approximately 70% of the site.
The proposed development will replace the existing building with a free-standing quick -service restaurant
with drive-thru service and improve existing landscaping on the site. Disturbed areas include
approximately 13,240 square feet or 90% of the site, however the existing No. 2 Canal will be minimally
impacted. Erosion control measures will be implemented to minimize sedimentation and protect the
existing Canal. The proposed site includes drainage improvements with area inlets that collect runoff at
the southwest and southeast comers of the site. Runoff is conveyed via storm sewer pipe and discharged
to the existing No. 2 Canal. A portion of the south bank of the No. 2 Canal approximately 60 square feet
in size will be disturbed for the construction of the outfall.
Water quality is also provided with a "snout structure" built in to the farthest downstream area inlet. This
structure is a hood device installed inside an inlet at the outlet pipe to prevent oil and debris from exiting
and passing through the remainder of the storm sewer system. (Please see attached cut sheet.) Chick-fil-
A will be responsible for the oil/debris removal and maintenance of this structure.
An Employee -Owned Corporation
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