Storm Water Management Plan required by this regulation shall contain the following information:
(a) Soil Erosion and Sediment Control: the plan shall include measures to insure that earth disturbing activities at the site during and after development will be managed in a manner that will not result in increased erosion and sedimentation from the site resulting in impact to water quality and that meet the standards set forth in Section 1311.09
.
(b) Post-Construction Water Quality and Quantity Control: the plan shall include measures to insure that the peak discharge rate of surface water runoff from the development site during and after construction will be 75% less than the pre-development peak discharge rate and to insure pollutants are reduced to the maximum extent practicable. The plan shall meet the standards set forth in Section 1311.11
and 1311.10
for post-construction water quality control.
(c) Preparation of Plans: All Storm Water Management Plans shall be prepared by a Professional Engineer experienced in the design and implementation of standard erosion and sediment controls and storm water management practices addressing all phases of construction.
(d) Compliance with all other Setback/Green Infrastructure Requirements: as necessary.
(e) Contents of Storm Water Management Plans: Shall include the Storm Water Pollution Prevention Plan (SWP3) required by either an individual NPDES Construction Activity Permit or Ohio EPA's NPDES Construction activity permit and incorporated here by reference. In addition to the SWP3, the applicant shall include the supplemental information set forth in Section 1311.06
. The contents of the Ohio EPA SWP3 include those requirements set forth in Section 1311.09
pertaining to soil erosion, sediment control and Section 1311.10
pertaining to post-construction water quality control and the following information:
(1) Description of the Plan of Construction: The following information shall be included in the Storm Water Management Plan:
A. Site Description:
1. Description of the prior land uses of the site.
2. A description of the nature and type of construction activity (e.g., low density residential, shopping mall, highway, etc.).
3. A description of the total area of the site and the area of the site that is expected to be disturbed (i.e., grubbing, clearing, excavating, filling or grading, including off-site borrow, fill or spoil areas and off-site utility installation areas).
4. An estimate of the impervious area and percent imperviousness for both the pre-construction and post-construction site conditions.
5. Existing soil data describing the soil and, if available, the quality of any discharge from the Site, including any potential sources of pollution which may reasonably be expected to affect the quantity of storm water discharges associated with construction activities.
6. A calculation of the runoff coefficients for both the pre-construction and post-construction site conditions.
7. The name and/or location of the immediate receiving stream or surface water(s) and the first subsequent named receiving water and the major river watersheds in which it is located and description of wetlands or other special aquatic sites at or near the site which will be disturbed or which will receive discharges from disturbed areas of the project.
B. A site map locating:
1. The larger common plan of development or sale
2. The development area
3. All pertinent surrounding natural features within 200 feet of the development site including, but not limited to:
- Water resources such as wetlands, springs, lakes, ponds, rivers and streams (including intermittent streams with a defined bed and bank)
- Conservation Easements
- Other sensitive natural resources
- The sensitive areas receiving runoff from the development
4. All off-site utility installation areas that are related to the planned project
5. Limits of earth disturbing activity of the site including associated off-site borrow or spoil areas.
6. Locations of unstable or highly erodible soils.
C. The existing and proposed topography shown in the appropriate contour intervals as approved by the Building Commissioner (generally one-foot contours are used).
D. The location and description of existing and proposed drainage patterns and facilities, including any allied drainage facilities beyond the development area and the larger common plan of development or sale.
E. Existing and proposed watershed boundary lines, direction of flow and watershed acreage.
F. Existing and planned locations of buildings, roads, parking facilities and utilities.
G. The location of all erosion and sediment control practices, including the location of areas likely to require temporary stabilization during the course of site development.
H. Sediment and storm water management basins noting their sediment settling volume and contributing drainage area.
I. Permanent storm water management practices to be used to control pollutants in storm water after construction operations have been completed.
J. The location of designated areas for the storage or disposal of solid, sanitary and toxic wastes, including dumpster areas, areas designated for cement truck washout and vehicle fueling.
K. The person or entity responsible for continued maintenance of all vegetative and/or mechanical BMPs for both the construction and post-construction phases of the development.
L. Long-term maintenance requirements and schedules of all BMPs for both the construction and post-construction phases of the development.
1. Long-term maintenance inspection schedules.
2. The person or entity financially responsible for conducting the inspections of, and the maintenance of, permanent storm water conveyance and storage structures and all other conservation practices.
3. The method of ensuring that funding will be available to conduct the long-term maintenance and inspections of all permanent storm water, soil erosion and sediment control and water quality practices.
M. The location of any existing or planned riparian and/or wetland setback areas on the property.
N. An implementation schedule which describes the sequence of major construction operations, the appropriate BMPs and the general timing (or sequence) during the construction process of when the measures will be implemented; and, who (which contractor) will be responsible for implementation (e.g., Contractor A will clear, grub and install perimeter controls and Contractor B will maintain perimeter controls until final stabilization; Contractor C will conduct and document the scheduled inspections.)
O. Location and description of any storm water discharges associated with dedicated asphalt and concrete plants covered by this regulation and the Best Management Practices to address pollutants in these storm water discharges.
P. Boundaries of wetlands and stream channels the owner intends to fill or relocate for which the owner is seeking approval from the US Army Corps of Engineers and/or Ohio EPA.
Q. The Storm Water Management Plan shall include a description of the Storm Water Management (SWM) practices to be used on the site. The SWM element of the Plan shall include, at a minimum, the following:
1. A map showing the location, drawn to scale, of permanent SWM conveyance, detention and retention structures, other SWM control structures and the SWM easements.
2. A general description of the SWM strategy proposed to meet this chapter.
3. Design calculations for all permanent SWM conveyance, detention and retention structures, and other SWM control structures.
4. Any other SWM related items required by the Building Commissioner.
R. This plan shall identify the subcontractors engaged in activities that could impact storm water runoff and information provided that these subcontractors understand their roles and responsibilities in complying with the practices required for storm water management.
(Ord. 70-12. Passed 11-13-12.)