(A) A stormwater management system shall be designed and installed for the development that will contain features to provide for flood protection, erosion control, and pollution abatement. The stormwater management system design shall conform to the Stormwater Design Standards contained in § 53.090, the Stormwater Master Plan and other standards specified by the City Engineer. The intent of these design standards is to encourage environmentally sound stormwater management practices; they should go beyond providing drainage facilities. Developments that sacrifice recharge and upland controls in order to maximize the number of lots will not be allowed. The city's stormwater management perspective includes the management of both water quantity and water quality. Stormwater management design shall blend into the natural environment and be aesthetically integrated into site design.
(B) Streams and wetlands subject to protection under Section 404 of the Clean Water Act shall be protected from the impacts of development. Setbacks from streams and wetlands shall be established and regulated to protect structures from flooding and erosion as well as to maintain water quality within the stream and wetland. The stormwater system design shall ensure that the quantity and quality of stormwater flows directed to these stream and wetlands are maintained as previous to development. Constructed wetlands (including bio-retention basins) shall be considered subject to these requirements. Existing wetlands shall not be used for stormwater management or stormwater runoff quality treatment.
(C) All development activity within a special flood hazard area designated by the Federal Emergency Management Agency (FEMA) or any other area as designated by the City Engineer shall comply with Chapter 151 of the Dublin Code of Ordinances. All development shall be designed to maintain the flood carrying capacity of the floodway such that the base flood elevations are not increased, either upstream or downstream. Furthermore, no fill shall be allowed to be placed in the 100-year floodplain without an equivalent volume of soil removed to compensate for the loss of the flood storage as defined in §53.200(G).
(D) The stormwater management system shall not create an adverse impact on stormwater quantity or quality in either upstream or downstream areas. Offsite areas which discharge to or across a site proposed for development shall be accommodated in the stormwater management plans for the development. No stormwater management plan shall be approved until it is demonstrated that the runoff from the project shall not overload or otherwise adversely impact any downstream areas.
(E) All proposed stormwater management systems shall be designed to prevent the pollution of groundwater resources by stormwater, promote safety, minimize health hazards, preserve natural features, and provide for recharge where appropriate. Neither submission of a plan under the provision herein nor compliance with the provisions of these regulations shall relieve any person from responsibility for damage to any person or property otherwise imposed by law.
(F) Where deemed necessary by the City Engineer, the applicant shall construct storm drains to handle on-site runoff; provide on-site drainage easements; provide off-site drainage easements; and provide for the conveyance of off-site runoff to an acceptable outlet in the same watershed. However, the on-site drainage easements may not encroach on required perimeter landscaping.
(G) Guidance on stream corridor protection zones (SCPZ) shall be referenced from § 53.200.
(H) Illicit discharges shall not be permitted. Any natural or man-made conveyance or drainage system, pipeline, conduit, inlet, or outlet (including natural surface flow patterns, depressions or channels traversing one or more properties) through which the discharge of any pollutant (including illegal sanitary sewer connections) to the stormwater management system shall not occur unless the connection is authorized under a discharge permit issued by the OEPA.
(Ord. 48-05, passed 9-6-05) Penalty, see § 53.999