APRIL 2, 2007SHAWNEE PLANNING COMMISSION MINUTESPAGE 17
The applicant is responsible for submitting final street improvement plans as an integral part of the site development plans to be submitted for a building permit.
12.The storm drainage improvements required for this development shall be designed in accordance with Division 4600, Storm Drainage, of the Shawnee Manual of Technical Specifications and Design Criteria. The enclosed and open components of the drainage system must be designed to convey the stormwater runoff from a 4 percent (25-year return period) design storm. The overflow components designed to convey the runoff from a 1 percent (100-year return period) design storm.
The applicant has submitted a preliminary storm drainage study with the site plan showing a conceptual drainage system, a drainage area map, and a drainage table summarizing the hydrologic and hydraulic analysis for the development site and all upstream tributaries. The preliminary study is adequate for the purposes of reviewing the site plan although the following design issues and any additional issues discovered during the review of the site development plans must be resolved prior to the issuance of a building permit.
While the additional stormwater runoff produced by the development site does not exceed the threshold where a private storm sewer system is required, City standards also do not allow runoff to discharge into a street from a driveway. Engineering staff has recommended that the applicant investigate using a pervious pavement product as an alternative to a convention drainage system. However, if the applicant determines that it would not be practical or cost effective, then the applicant is responsible for constructing a collection system at both approaches.
The required street improvements will necessitate the removal of a grate inlet near the northwest corner of the development site and the removal and replacement of a curb inlet near the northeast corner with a junction box.
Complete information will need to be provided for the drainage system, including drainage areas and gutter flow directions, within the public street rights-of-way.
The applicant is responsible for submitting a final storm drainage plan as an integral part of the site development plans to be submitted for a building permit.
13.The applicant is responsible for submitting an impervious area plan prior to the issuance of any Certificate of Occupancy. A printed copy of the plan must be submitted together with an electronic copy in AutoCAD© format, using coordinates based in the Kansas North State Plane Coordinate System of 1983, North Zone (NAD-83), to the City’s