HomeMy WebLinkAboutSite Certifications - 03/02/2000March 15, 2000
Mr. Jay Barber
City of Fort Collins
Utility Services Stormwater
700 Wood Street
Fort Collins, Colorado 80522
RE: Landings Bay Drainage Certification
Dear Jay:
N O R T H E R N
ENGINEERING
SERVICES INC
The following letter is a partial certification of the drainage facilities as installed at Landings Bay.
It covers the existing detention pond volume, the overflow weir dimensions, and the new 36"
storm sewer invert and location. This certification is based on site visits March 10, 2000 by
Northern Engineering Services and by a field survey by RJL Surveys in February 2000. Attached
is a plot of the proposed grading by Northern Engineering Services and the field verified storm
drainage improvements located by RJL Surveys.
Essentially, all of the improvements required for a partial drainage certification were installed at
the time of the inspection. The 36" storm sewer with flared -end section was in place and the weir
constructed alongside the ditch. The remainder of the Landings Bay site is presentlybeing
constructed and will require a future drainage certification inclusive of the entire site.
The volume of the existing detention pond has been estimated and the following results were
obtained: .11
Required Design Volume — 53,017 cubic -feet at WSEL 5030.57
Actual Volume — 51,585 cubic -feet at WSEL 5030.43 (lowest overflow elevation)
Volume at 100-year WSEL 5030.57 — 54,272 cubic -feet
Items that will need to be completed for Landings Bay:
The outlet to the existing 18" storm sewer at the north end of
the pond will need to be cleaned out.
The remainder, of the site, aside from the detention pond, 36"
storm sewer, and the weir will need to be constructed.
The detention pond area will need to be landscaped.
Thank you for your time and consideration. Please feel free to contact Northern Engineering
Services if you have any further questions or comments concerning Landings Bay.
Sincerely,
NORTHERN E INEERING SER
Veg*an. Ne
Project Engineer
RoW Curtis, P.E.
Project Manager
420 SOUTH HOWES, SUITE 202, FORT COLLINS, COLORADO 8052.1, (970) 221-4158, FAX (970)
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