1999-10-28 Drainage CalculationsKUUSISTO LTD
SST. 1959
Engineering • Planning ~ Surveying • Landscape Architecture
October 28, 1999
Peter J. Carlson, P.E.
City Engineer, City of Albertville.
S.E.H.-R.C.M.
605 Franklin Avenue NE
P.O. Box 51
St. Cloud, MN 56302-0051
RE: Drainage Calculations
Mooney Development Corporation
Albertville, MN (A-ALBEV 0001.00. 14.00),
Dear Mr. Carlson:
Attached are the drainage calculations for the Mooney Addition project. The project
proposes construction of a gas station/convenience store on the south portion of the site.
During the review process, City officials requested that we develop a concept site plan
for the north portion of the site as well to assure that the remaining portion of the site
adequately provides for future development. We have revised our proposal to
conceptually show a future fast food restaurant on the north portion of the site.
Although :this ,project will be constructed in two stages, the gas station/convenience store
being the first, our drainage calculations are based on the site being fully developed. This
includes all paved surfaces and the pond sized assuming the retaining wall is in place.
All calculations were performed with HydroCAD software. At this time, the runoff from
the proposed site flows through a swale ko the west .across .the north portion of the site.
The existing flow rate for the 100-year storm event was calculated to be 5.29 cfs. The
post-development outflow from the on-site retention pond was calculated to be 3:86 cfs
for the 100-year event. The 100-year HWL for the pond is 956.6.
If you have any questions regarding these calculations, please feel free to call. My direct
dial phone number is (612) 933-8258, ext. 130.
Sincerely,
Lee Koppy, Project Engineer (E.LT.)
RLK-Kuusisto, Ltd.
Offices: Hibbing Minnetonka St. Paul Twin Ports
(612) 933-0972 6110 Blue Circle Drive Suite 100 Minnetonka, MN 55343 fAX (612) 933-1153