The following information shall be submitted to the Village Engineer as the plan required under Section 1481.02.
(a) An overall drainage plan of the proposed development area showing existing and proposed grading, existing and proposed runoff flow paths and drainage facilities, contributing areas draining to the drainage system, and the predominant soil types with runoff coefficients.
(b) Plan view, typical cross-sections and pertinent details of the proposed detention basin and its primary and emergency outlet control structure(s).
(c) Detention basin reservoir capacity versus reservoir water surface elevation calculations.
(d) Outlet control structure discharge versus reservoir water surface elevation hydraulic calculations, including the assumptions or calculations made to determine the existing drainage system hydraulic gradient or water surface elevation at the outlet control structure discharge point.
(e) Inflow-outflow hydrographs, both in tabular and graphical form for the one year storm, the Critical Storm and all storms exceeding the Critical Storm. The required inflow hydrographs shall include both pre-development and post- development conditions.
(f) The assumptions and/or calculations utilized in determining the inflow hydrographs in accordance with the accepted hydrologic methods.
(g) Hydraulic gradient calculations for the proposed storm drainage system emptying into the detention basin based on the Critical Storm. Design year and other storm design year frequencies may be required by the Village Engineer for the storm drainage system hydraulic grading calculations, should the Engineer deem necessary. (Ord. 1990-13. Passed 2-12-90.)