(a) Comprehensive Stormwater Management Plan Required. The applicant shall develop a Comprehensive Stormwater Management Plan describing how the quantity and quality of stormwater will be managed during and after construction is complete. The Comprehensive Stormwater Management Plan shall be prepared by a Professional Engineer and shall include supporting calculations, plan sheets and design details. The Plan will illustrate the type, location, and dimensions of every stormwater management practice incorporated into the site design. The chosen stormwater management practices, facilities and improvements must address runoff within the site as well as flooding that may be caused by the development upstream and downstream of the site. The chosen stormwater management practices, facilities and improvements must also minimize impacts to the physical, chemical, and biological characteristics of on-site and downstream water resources and avoid predictable degradation of water resources.
(b) Contents of Comprehensive Stormwater Management Plan. The Comprehensive Stormwater Management Plan shall meet the requirements of the latest edition of Ohio EPA's General Permit Authorization For Stormwater Discharges Associated With Construction Activity Under The National Pollutant Discharge Elimination System and shall provide the following information:
(1) Plans must include the following notes:
A. At the end of construction, all stormwater pipes, basins, channels, etc. shall be cleaned out of all sediment accumulation and restored to the original design as shown per these plans.
B. Forty-eight hours prior to any earth disturbance work, the Contractor shall notify the City of Springfield, Service Department.
C. All mud/dirt tracked onto roads from the site, due to construction, shall be promptly removed at the end of each day.
D. No construction shall commence until all City of Springfield permits and connection fees have been issued as required.
E. Stormwater control facilities composed of straw are not permitted.
F. Clearing, grading, and equipment storage is prohibited within twenty-five (25) feet of all water resources unless otherwise approved by the Service Director or desginee.
G. Where construction activity is necessary within ten (10) feet of a water resources high water mark, perimeter protection using Filtrexx erosion control socks or similar material shall be used.
H. Construction projects scheduled to last six (6) months or more shall not use silt fence as perimeter protection; instead, Filltrexx erosion control sock or similar material shall be used.
I. Dewatering discharges shall not be directed into the City of Springfield's stormwater system without the prior approval of the Service Director or designee.
(2) Location of all existing easements, covenants and restrictions impacting each stormwater management practice, facility, or improvement.
(3) An Inspection and Maintenance Plan designed to ensure that all pipes and channels built to convey stormwater to the stormwater control facility, as well as all structures, improvements, and vegetation provided to control the quantity and quality of the stormwater discharged from the facility serves its designed purpose through its expected period of use shall be submitted as a stand-alone document for review and approval by the Service Director or designee during the Plan approval process. At a minimum, the Inspection and Maintenance Plan shall include a method and frequency for the following activities:
A. Inspection of all permanent structures,
B. Debris/clogging control through appropriate removal and disposal,
C. Vegetation control (mowing, harvesting, eradication of undesirable plants),
D. Erosion repair,
E. Non-routine maintenance should include pollutant and sediment removal and the "rejuvenation" or replacement of filters and appropriate soils, and
F. Disposal of collected pollutants, sediments, and filter media in accordance with local, state, and federal regulations.
G. Inspection and Maintenance Plans shall include language affirming the following:
(i) The City of Springfield has the authority and right to enter upon the development area to conduct inspections as necessary to verify that the stormwater management practices are being maintained and operated in accordance with this regulation.
(ii) Notice that the City of Springfield maintains public records of the results of site inspections for the period of time specified in the City of Springfield's record retention schedule, shall inform the site owner(s) or organization responsible for maintenance (by written notice served on the tax mailing address for the subject land) of the inspection results, and shall specifically indicate any corrective actions required to bring the stormwater practices into proper working condition.
(iii) If the City of Springfield notifies the site owner(s), or other entity responsible for maintenance, of maintenance deficiencies that require correction, the specific corrective actions shall be taken within thirty (30 days of the service of the notice; unless the City grants an extension of time to complete correcting deficiencies due to the impracticality of completing the correction of deficiencies within thirty (30) days.
(iv) Maintenance deficiencies not corrected within thirty (30) days may be declared a public nuisance in accordance with Chapter 1323 of these codified ordinances.
(v) The method of funding long-term maintenance and inspections of all stormwater management practices, facilities and improvements.
(4) Calculations required. The applicant shall submit calculations for projected stormwater runoff flows, volumes, and timing into and through all stormwater management facilities for flood control, channel protection, water quality, and the condition of the habitat, stability, and incision of each water resource and its the floodplain, as required in Section 961.10 of this regulation. These submittals shall be completed for both pre- and post-development land use conditions and shall include the underlying assumptions and hydrologic and hydraulic methods and parameters used for these calculations. The applicant shall also include critical storm [See Section 961.10(c)] determination and demonstrate that the runoff from upper watershed areas have been considered in the calculations. Redevelopment projects shall only submit calculations at the request of the City.
(5) The Comprehensive Stormwater Management Plan shall include a time schedule for completing all elements of the work to construct Comprehensive Stormwater Management Plan facilities and achieve final stabilization.
(6) Detention exemption. When the total detention required on a development area is under 1,000 cubic feet, the City may, upon the request of the developer, waive the detention requirements of this chapter; provided, however that the City shall not grant a waiver if it is determined that storm water drainage would be a threat to adjacent properties if no detention were to be provided or if it is determined that the public sewer system downstream of the development area is not adequate to handle the increased storm flow.
A. Residential development of three units or less that are not part of a larger common plan of development or redevelopment are exempt from the detention requirements of this chapter; provided, however that the City shall not determine that storm water drainage would be a threat to adjacent properties if no detention were to be provided or if it is determined that the public sewer system downstream of the development area is not adequate to handle the increased storm flow.
(7) The Comprehensive Stormwater Management Plan shall conform to the performance standards specified in Section 961.10.
(Ord. 19-289. Passed 12-10-19.)