(A) It is recognized that (with the possible exception of the White River and Mississinewa River) the smaller streams and drainage channels serving the county may not have sufficient capacity to receive and convey storm water runoff resulting from continued urbanization. Accordingly, the storage and controlled release rate of excess storm water runoff shall be required for any new major subdivision residential development, commercial, industrial or institutional development, and any commercial, industrial or institutional redevelopment in the county.
(B) Exceptions to the requirement are minor subdivisions as described in the county Subdivision Control Ordinance. In addition, the Board, after thorough investigation and evaluation, may waive the requirement of controlled runoff set out in this chapter.
(C) The release rate of storm water from development, redevelopments, and new construction requiring controlled release may not exceed the storm water runoff from the land area in its present state of development. The developer must submit to the Board detailed computations of runoff before and after development, redevelopment or new construction, which demonstrate that runoff will not be increased. These computations must show that the peak runoff rate after development for the 100-year return period storm of critical duration must not exceed the 10-year return period pre-development peak runoff rate.
(Ord. 00-22, passed 12-28-00; Am. Ord. 2001-17, passed 1-14-02)