HomeMy WebLinkAboutLot Certifications - 07/15/1997 (3)AYRES
ASSOCIATES
July 15, 1997
Mr. Basil Hamdan
City of Fort Collins Water Utilities
Stormwater Department
235 Mathews Street
Fort Collins, Colorado 80522
Re : Swallow 's Nest drainage certification
Dear Basil ,
STORMWATER
RECEIVED
JUL 1 5 1997
During the last week we have worked closely with RD Stewart to grade the above mentioned
site such that the des ign detention pond volume is met. As I told you during our phone
conversation on July 14, 1997, it has proved pract ically impossible to meet the des ign volume.
There are a couple of reasons for this :
• The building floor plan requires that the sidewa lks be raised over the design elevations in
order to meet handicap access requirements . As a result of raising the sidewalks , some
storage vo lume in the parking lot is lost.
• A playground constructed by CARE Housing on the above-referenced site was extended
into the detention pond in question (in a easement). The playground was built at then
exist ing grades without accounting for future grad ing in the detention pond (which would
have involved a couple feet of cut). ·
As a result of these items , it proves to be impossible to meet the detention pond design volume .
I have observed the site and the contractor has done everything he can to fully maximized the
detention storage avai lable (aside from tearing out the playground). The pond spillway has
been graded such that sto rmwater will sp ill out of the pond before infringing into the 1-foot
freeboard buffer for the bu ildings . The result ing detention volume is 0.44 acre-feet (versus 0 .52
acre-feet in the design ).
All other grad ing aspects have been constructed according to our design and the surface
drainage patterns will follow the intended patterns . A blueline print of the design showing as
built spot elevations has been included for your review .
As of my last visit , the orifice plate on the pond outlet had not been installed . The contractor
indicated that the plate has been ordered and should arrive within the next week. He is willing
to install a temporary plate until the arrival of the final plate if necessary to secure the release of
occupancy perm its .
Owen Ayres & Associates, Inc.
Engineers/Scientists /Surveyors
3665 JFK Parkway, Building 2, Suite 300, P.O. Box 270460, Fort Collins, CO 80527
(970) 223-5556, Denver Metro (303) 572-1806, FAX (970) 223-5578
Printed on recycled paper
HAMD-7 .LTR
34-0541 .00
Mr. Basil Hamdan
Page Two
July 15, 1997
If you need further clarification, please call me as soon as possible . I will be out of the office
between July 17 (Thursday) and July 21 (Monday) and need to get this issue resolved before I
leave.
Sincerely ,
ries & Associates, Inc.
Scott Queen, P.E.
Civil Engineer
SQ:sp
Enclosure
HAMD-7 .LTR
34-0541 .00