HomeMy WebLinkAboutCorrespondence: Kimley-Horn Detention Sizing/ROW Waiver Request
Suite 2125
205 W. Wacker Drive
Chicago, IL
60606
August 23, 2012
Gary Duncan
Assistant City Engineer, City of Carmel
One Civic Square
Carmel, IN 46032
(317) 571-2441
Re: Olive Garden Restaurant – 10206 Michigan Rd., Carmel IN
Detention Sizing Including Adjacent Right-of-Way Waiver Request
Dear Mr. Duncan:
Per the City of Carmel Stormwater Technical Standards Manual Section 302.06, “Detention basins shall be
sized to detain the runoff from the fully developed right-of-way per the City of Carmel 20-year Thoroughfare
Plan across all frontages, regardless of existing watershed boundaries or drainage breaks/divides. The acreage
of the full right-of-way width shall be included in the overall acreage of the development in determining the
allowable release rate”.
Due to site constraints, the site cannot detain the fully developed Michigan Road right-of-way adjacent to the
development. Instead, the proposed site detention calculation has been designed for the developed Michigan
Road right-of-way to the centerline of Michigan Road which includes 0.49 acres of impervious area. Michigan
Road right-of-way in its current condition is built out with a minimum of two-lanes in each direction with
additional turn lanes. Michigan Road right-of-way also has its own storm sewer drainage system in which the
current roadway drains. If Michigan Road were to add additional lanes, the current roadway storm sewer
system would be upgraded/sized to accommodate.
Further detention cannot be included within the Olive Garden development as the current site already
includes three detention areas all reaching their maximum elevation of 4 feet per City code. In addition,
pavement areas are not available to be used as detention as we’re at the City codes minimum parking count
requirement.
While site constraints prevent full compliance Section 302.06 of the Stormwater Technical Standards Manual, we are
still providing detention for half of the Michigan Road right-of-way. Therefore, we respectfully request a waiver of
the right-of-way detention requirement.
Please contact me if you have any further questions or require any additional information.
Sincerely,
Kimley-Horn and Associates, Inc.
Justin Muller, P.E.
1