Storage facilities located within the regulatory floodplain shall:
(B) Store the required amount of site runoff to meet the release rate requirement under all stream flow and backwater conditions in the receiving stream up to the 10-year flood elevation;
(C) Detention volume provided by enlarging existing regulatory floodplain storage without providing a structure controlling discharge (on-stream detention) will be allowed only as a variance. The applicant must demonstrate that flood damages are not increased and the development will not increase flood flows for both the 2-year and 100-year floods on the stream with developed conditions on the site; and
(D) The Administrator may approve designs which can be shown by detailed hydrologic and hydraulic analysis to provide a net watershed benefit not otherwise realized by strict application of the requirements in divisions (A) through (C) above.
(Ord. 06-0383, passed 3-15-06)