A profile and mapping of floodwater depths and coverage shall be prepared for the property for the 2-year, 10-year, and 100-year events. Directions of flow and velocities shall also be reported for critical points in the drainage system.
(A) Detention. Minimum available storage to be provided in a detention basin shall be based upon the stormwater runoff from the 100-year, 24-hour event and reservoir routing (also called level pool), or equivalent.
(B) Streets. Detention storage on streets is strongly discouraged, and will only be allowed after other methods have been exhausted. Detention storage on streets will then only be allowed according to the following criteria:
(1) Detention storage will only be allowed on collector, or side streets that do not provide the sole access to an area.
(2) Detention storage on streets shall not cause ponding depths to exceed curb heights by more than one inch, or a total of seven inches, whichever is greater. No street shall remain flooded for more than eight hours for any event less than or equal to the 100-year event.
(3) The Village accepts no liability for any property damage or personal injury resulting from inundation of any street caused by storing of stormwater detention on the pavement. The developer and the developer's engineer must provide a letter to the Village accepting all such liability.
(C) Parking Lots. Detention storage will be allowed on parking lots on private developments according to the following criteria:
(1) The maximum ponding depth for parking lots is seven inches.
(2) The Village accepts no liability for any property damage or personal injury resulting from inundation of any parking lot caused by storing of stormwater detention on the pavement. The developer and the developer's engineer must provide a letter to the Village accepting all such liability.
(Ord. 05-2528, passed 7-26-05)