(a) Comprehensive Storm Water Management Plans required by this Chapter shall meet the minimum technical requirements listed in Ohio EPA's Construction General Permit, methods established in the Rain Water and Land Development Manual or other recognized design manuals approved by the Director of Engineering Services, and the following design criteria:
(1) Storm water management practices shall function as an integrated system that controls flooding and minimizes the degradation of the physical, biological and chemical integrity of the water resources receiving storm water discharges from the site.
(2) Storm water management practices shall be designed to achieve the storm water management objectives of this Chapter, to be compatible with the proposed post-construction use of the site, to protect the public health, safety, and welfare, and to function safely with minimal maintenance.
(3) To the extent that site characteristics allow, proposed redevelopment project designs shall include storm water management practices that are designed to result in treatment of twenty percent (20%) of the WQv of the previously developed area using a practice meeting Table 4a/4b requirements of the Ohio EPA’s Construction General Permit.
A. “Redevelopment” refers to alterations of a property that change the footprint of a site or building which results in greater than one (1) acre of land disturbance.
B. When possible, all practical alternatives permitted above shall be implemented within the drainage area of the proposed redevelopment project.
(4) All storm water management practices shall have easements sufficient to provide access to the City of Sandusky for maintenance and inspection purposes.
(5) When developing a Comprehensive Storm Water Management Plan, a combination of nonstructural and structural storm water management practices shall be used to control storm water quantity and protect water quality. In meeting this requirement, the following shall apply:
A. Nonstructural and structural storm water management practices shall be designed in accordance with the most recent version of the Rainwater and Land Development Manual, as specified within this Chapter, and/or in accordance with specifications provided by the Director of Engineering Services.
B. Nonstructural storm water management practices shall be recorded on all property deeds and shall remain unaltered by subsequent property owners.
C. In designing storm water basins, properly designed detention and/or retention basins with water quality benefits shall be used to the maximum extent practicable. Detention/retention basins shall not be constructed in streams. The applicant must demonstrate the water quality benefits achieved to the Director of Engineering Services.
D. Where feasible, Infiltration Post-Construction Practices, as depicted in Table 4b of the Ohio EPA’s Construction General Permit must be the water quality storm water control measures used. Separate storm water control measures may be used for peak discharge control and water quality treatment.
(6) Calculation Methods.
A. The engineer selecting the calculation method and/or performing the calculations shall do so with full knowledge of the method's limitations, applicable conditions, and degree of accuracy and shall state these in the calculations submitted to the Director of Engineering Services for review.
B. The Director of Engineering Services may reject any calculation method he/she deems inappropriate for the given situation.
C. The preferred design method is the Critical Storm Method as outlined in the Rain Water and Land Development Manual. Rational Method shall be the minimum design.
(Ord. 22-061. Passed 3-28-22.)