(A) It is recognized that most streams and drainage channels serving the city do not have sufficient capacity to receive and convey stormwater run-off from continued urbanization. Accordingly, the storage and controlled release of excess stormwater run-off shall be required for all developments and redevelopments (as defined in § 56.003) located within the city. Release rate requirements, downstream restriction considerations, acceptable outlet, adjoining property impact considerations and compensatory floodplain storage rates are detailed in the City of Lebanon Stormwater Technical Standards Manual.
(B) (1) The city Stormwater Management Board is authorized, but not required, to classify certain geographical areas as “designated drainage areas.” In determining designated drainage areas, the city Stormwater Management Board shall consider such factors as topography, soil type, capacity of existing drains, and distance from adequate drainage facility. Land that does not have an adequate outlet, taking into consideration the capacity and depth of the outlet, may be designated as a designated drainage area by the city Stormwater Management Board. Special terms and conditions for development within any designated drainage area shall be included in the stormwater management permit.
(2) The city Stormwater Management Board may establish an infrastructure development fee (“IDF”) rate for a designated drainage area. The city Stormwater Management Board may also waive an established infrastructure development fee for consideration of land rights, construction costs, or other agreeable interests.
(3) The magnitude of the IDF for a given parcel will be determined by the declared IDF rate and the volume of detention storage necessary to prevent an increase in downstream flow rates and/or upstream flooding elevations. A master hydrologic and hydraulic model for the designated drainage area will be developed and maintained under the direction of the city Stormwater Management Board.
(4) All developments and redevelopments must submit a hydrologic model with accompanying hydrologic parameter calculations for the parcel(s) being developed. The model and hydrologic parameters will be incorporated into the master hydrologic and hydraulic models, under the direction of the city Stormwater Management Board, to determine the detention storage necessary to mitigate any detrimental effect of the development on the stormwater drainage for the city. The resulting detention volume will be multiplied by the IDF rate to establish the IDF for the development. The IDF rate established by the city Stormwater Management Board shall be subject to approval by the Common Council for the city.
(Ord. 06-15, passed 11-13-2006; Ord. 2015-01, passed 1-26-2015)