Maximum allowable run-off shall be limited to:
(A) One cfs/acre (one cubic foot per second per acre) for development on unimproved sites of two acres or less;
(B) Limited to the flow that would occur during a five-year storm under existing conditions for any undeveloped sites larger than two acres;
(C) For developed sites undergoing redevelopment or expansion:
(1) If 30% or more of the impervious area is increased or modified, detention must be provided for the entire site and outflow is not to exceed what would occur for a five-year storm under existing conditions. For example, if more than 30% of an area that will not absorb storm water such as a parking lot or roof area is increased, then a water detention facility must be provided for the entire site to control and detain the storm water outflowed so that it will not exceed that of a five-year storm.
(2) If less than 30% of the site is affected, then detention shall be provided for only the area that is developed or modified.
(D) Limited to the flows that will not cause damage or exceed the capacity of any downstream drainage facilities within the village.
(2001 Code, § 34-6-38)