HomeMy WebLinkAboutDrainage Reports - 09/12/1991STEWART&ASSOCIATEc-f"'a1 roved Report
Consulting Engineers and Surveyors Date 1Al
September 3, 1991
Storm Drainage Utility
City of Fort Collins
P.O. Box 580
Fort Collins, Colorado 80522
Dear Glen:
The Helmshire Inn is located at the Southeast corner of South College
Avenue and Edwards Street. It is an existing bed and breakfast establishment
that is adding 1000 square feet of asphalt parking. There is some interior
remodeling that is also being done.
The site drains from Southwest to Northeast. College Avenue has a high
point in this block and drains both North and South. There is a catch basin
in the College Avenue gutter at the Edwards Street corner. It accepts only
College Avenue runoff, and I believe the storm drain flows back South to
Pitkin Street. There does not appear to be any storm water overtopping of
College Avenue at this intersection.
Edwards Street drains East in the South gutter. The alley drains from
South to North in the inverted crown of the existing asphalt. The main parking
area has an inverted crown that drains from West to East and flows North
in the alley to the Edwards Street gutter. The existing asphalt parking
spaces on both sides of the alley drain to the center of the alley.
It is proposed to construct the six new parking spaces so that they
also drain to the centerline of the alley.
The existing site does not have any offsite drainage entering it other
than the alley flows entering from the South. The runoff from this site
does not flow onto any private property. The entire runoff flows to the
Edwards Street south gutter.
The existing site does not have onsite storm water detention. The
proposed additional asphalt parking develops 0.10 cubic feet per second of
runoff in a ten—year storm. .
Because of the very small increase of runoff and no practical means
of detention, we are requesting a variance to the onsite detention
requirement. We are not proposing any erosion control devices for this small
James H. Stewart
and Associates, Inc.
214 N. Howes Street
P.O. Box 429
Ft. Collins, CO80522
3031482-9331
ff
Mr. Glen Schlueter
September 3, 1991
Page 2
construction project. When the 1000 square feet is stripped of topsoil,
it will be lower than the alley asphalt and, therefore, not cause silting
onto the alley. It is expected the base and asphalt will be placed in a
very short period of time so that no erosion will occur.
The runoff calculations and the drainage plan are enclosed as part of
this report. If you have any questions regarding thissite, please call.
Sincerely,
Richard A. Rutherford, P. E. & L.S.
President
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