The development drainage map shall include sufficient data for the Village to check the feasibility of the drainage system as proposed by the developer. The following data shall be provided:
(a) Hydrologic Calculation. At all critical points within the development including catch basins:
(1) Tributary drainage areas delineated on the map.
(2) Times of concentration.
(3) Intensity.
(4) Runoff coefficients.
(5) Design flow.
(b) Hydraulic Calculations.
(1) Sufficient documentation to indicate the results of the investigation into the adequacy of the downstream drainage system to handle the runoff from the proposed development.
(2) This will determine the maximum allowable release rate for the proposed development and, in turn, the amount of storm water storage that will be required.
(3) The plan and profile of all drainage ways shall be provided, imposed upon which shall be the design energy and hydraulic grade lines.
(4) Sizes and types of drainage improvements, including special structures, typical sections, right-of-way width and fencing.
(5) Supporting calculations for upstream and downstream channel capacities as they affect overflow, erosion or backwater within the development. Such calculations shall be substantiated by such additional information as is required to determine profile and cross section of the upstream and downstream channel reaches under consideration.
(6) Sufficient contours and grading details to indicate proposed street grades and elevations throughout the development.
(Ord. 2021-08. Passed 12-13-21.)