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This chapter applies to development areas having new or relocated projects involving highways, underground cables, pipelines, subdivisions, industrial projects, commercial projects, building activities on farms, redevelopment of urban areas and all other land uses not specifically exempted. This chapter does not apply to:
(a) Land-disturbing activities related to producing agricultural crops or Silviculture operations regulated by the Ohio Agricultural Sediment Pollution Abatement Rules (1501: 15-3-01 to 1501: 15-3-09 of the Ohio Administrative Code) and existing at the time of passage of this regulation.
(b) Strip mining operations regulated by Chapter 1513 of the Ohio Revised Code and existing at the time of passage of this regulation.
(c) Surface mining operations regulated by Chapter 1514 of the Ohio Revised Code and existing at the time of passage of this regulation.
(d) Construction activities that do not include the installation of any impervious surface (e.g., soccer fields), abandoned mine reclamation activities regulated by the Ohio Department of Natural Resources, stream and wetland restoration activities, and wetland mitigation activities.
(e) Linear construction projects, (e.g., pipeline or utility line installation), which do not result in the installation of impervious surface and are independent of other construction projects (not part of a larger common plan of development or sale). However, linear construction projects must be designed to minimize the number of stream crossings and the width of disturbance and achieve final stabilization of the disturbed area as defined in the "Definitions" section of this chapter.
(f) Transportation projects that are subject to industry specific Ohio EPA Rules are exempt from these rules.
(g) It is not the role of the community to point out each and every part of the rules and how to implement them on the individual job sites. It is the project owner's responsibility to be proactive in meeting the intent, purpose and requirements of these regulations.
(Ord. 2013-41. Passed 9-24-13.)
In implementing these regulations the Community Engineer or other Community officials may consult with the local county SWCD, state and federal agencies and other technical experts as necessary. Any costs associated with such consultations may be assessed to the applicant or his or her designated representative.
(Ord. 2013-41. Passed 9-24-13.)
In order to control Post-Construction water quality damage and damage to public and private lands, the owner of each development area shall be responsible for developing a Post-Construction Storm Water Management Plan.
(a) This plan will be combined with the Construction Site Conservation Plan that is also developed for the site.
(b) This plan will contain a description of controls appropriate for each construction operation covered by these regulations, and the operator will implement such controls in a timely manner.
(c) The BMPs used to satisfy the conditions of these regulations shall meet the standards and specifications in the current edition of the Ohio Rain Water and Land Development manual, ODOT Post-Construction storm water standards, or other manual that is acceptable to the Community Engineer or Ohio EPA.
(d) The plan must make use of the practices that preserve the existing natural condition to the Maximum Extent Practicable (MEP).
(e) To meet the Post-Construction requirements of this regulation, the Post-Construction Water Quality Plan must contain a description of the Post-Construction Best Management Practices (BMPs) that will be installed during construction for the site and the rationale for their selection. The rationale must address the anticipated impacts on the channel and floodplain morphology, hydrology, and water quality.
(f) Structural post-construction BMPs cannot be installed within a State surface water (e.g., wetland or stream) unless it is authorized by a Clean Water Act Section 401 water quality certification and/or Clean Water Act Section 404 Permit.
(g) This plan will identify 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.
(h) Long-term maintenance requirements and schedules of all BMPs for both the construction and Post- Construction phases of the development will be provided as a stand alone document to the Post- Construction operator and the Community.
(i) This plan will contain long-term maintenance inspection schedules, including the printed name and contact point of the Post-Construction landowner (e.g., president of the homeowners association, store manager, apartment complex manager, etc.).
(j) This plan will identify the person or entity that will serve as the Post-Construction operator who will be financially responsible for maintaining the perpetual inspection and maintenance of permanent storm water conveyance and storage structures and other conservation practices.
(k) 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 will be identified.
(l) Maintenance plans must ensure that pollutants collected within structural Post-Construction practices, be disposed of in accordance with local, state, and federal regulations.
(m) Maintenance plans must include legally binding perpetual maintenance easements and agreements. Easement documents must provide for community access.
(n) The Post-Construction Plan will also contain the following information depending on the size of the development sites as well as any additional information required by the community engineer:
(1) Development Sites Smaller than Five Acres: A development site that will disturb one (1) or more, but less than five (5) acres of land and is not a part of a larger common plan of development or sale which will disturb five or more acres of land shall identify:
A. Storm Water Issues: A statement as to how the decreased storm water quality that will be caused by the planned development project will be handled
B. Description of Measures: A description of the BMPs that will be installed during the construction process to control pollutants in storm water discharges that will occur after construction operations have been completed.
C. Upland Areas: Structural measures placed on upland areas to the degree attainable.
D. Map: A map of the entire site showing the overall development.
E. Riparian and/or Wetland Setback: All riparian and wetland setback areas will be identified on the plans. They will also be marked in the field prior to the start of construction.
F. BMPs: Best Management Practices used in the Post-Construction Water Quality Plan may include but are not limited to:
1. Permanent Storm Water Detention ponds that provide extended detention of the water volume.
2. Flow attenuation by use of open vegetated swales and natural depressions
3. Onsite infiltration of runoff
4. Sequential systems that combine several practices
5. Permanent conservation easements, preferably with the easement being held by a third party with no vested interest in ever seeing the property developed
6. Natural Channel Design for drainage ways
7. Bioengineering in drainage ways
8. Recreating floodplains
9. Chemical and biological filters in storm sewer inlets
10. Sand Filters
11. Allowing roof water from buildings to run across lawn areas to remove pollutants
12. Onsite sewage disposals system replacement or conversion to sanitary sewers
13. Low Impact Development Design
14. Countryside Development Design meeting the criteria of the Western Reserve Resource Conservation and Development Area.
15. Aquatic benches in Retention Basins and ponds.
C. Technical Basis: The plan will contain a statement of the rationale utilized to select the BMPs used to control pollution and to maintain and protect water quality.
(2) Development Sites 5 Acres or Larger: A development site that disturbs five (5) or more acres of land or will disturb less than five (5) acres, but is a part of a larger common plan of development or sale, which will disturb five (5) or more acres of land shall identify:
A. Storm Water Detention: The Post-Construction BMP(s) chosen must be able to detain storm water runoff for protection of the stream channels, stream erosion control, and improved water quality.
B. Structural BMPs: Structural (designed) Post-Construction storm water treatment practices shall be incorporated into the permanent drainage system for the site.
C. Properly Sized BMPs: The BMP(s) chosen must be sized to treat the water quality volume (WQv) and ensure compliance with Ohio's Water Quality Standards in OAC Chapter 3745- 1. The WQv shall be equivalent to the volume of runoff from a 0.75-inch rainfall and shall be determined according to the following equation:
1. WQv = C * P * A / 12 where: WQv = water quality volume in acre-feet C = runoff coefficient appropriate for storms less than 1 inch (either using Table 1 or the following formula: C=0.858i - 0.78i2 + 0.774i + 0.04 where i=fraction of post-construction impervious area) P = 0.75 inch precipitation depth A = area draining into the BMP in acres.
Table 1 Runoff Coefficients Based on the Type of Land Use
Land Use | Runoff Coefficient |
Industrial & Commercial | 0.8 |
High Density Residential (> dwellings/acre) | 0.5 |
Medium Density Residential (4 to 8 dwellings/acre) | 0.4 |
Low Density Residential (< 4 dwellings/acre) | 0.3 |
Open Space and Recreational Areas | 1.2 |
D. Where the land use will be mixed, the runoff coefficient should be calculated using a weighted average. For example, if 60% of the contributing drainage area to the storm water treatment structure is Low Density Residential, 30% is High Density Residential, and 10% is Open Space, the runoff coefficient is calculated as follows (0.6)(0.3) + (0.3)(0.5) + (0.1)(0.2) = 0.35.
E. An additional volume equal to 20 percent of the WQv shall be incorporated into the BMP for sediment storage and/or reduced infiltration capacity. The BMPs will be designed according to the methodology included in the Ohio Rainwater and Land Development manual, ODOT Post-Construction storm water standards, or other manual that is acceptable to Ohio EPA. .
F. The BMPs listed in Table 2 below shall be considered standard BMPs approved for general use. However, communities with a regulated MS4 may limit the use of some of these BMPs. BMPs shall be designed such that the drain time is long enough to provide treatment, but short enough to provide storage available for successive rainfall events and avoid the creation of nuisance conditions. The outlet structure for the post-construction BMP must not discharge more than the first half of the WQv in less than one-third of the drain time.
Table 2: Target Drain Times for Structural Post-Construction BMPs
BMPs Suitable for Drainage Areas 5 Areas | BMPs Suitable for Drainage Areas < 5 Acres | ||
Best Management Practice | Drain Time | Best Management Practice | Drain Time |
Dry Extended Detention Basin* | 48 hours | Infiltration Basins^ | 24-48 hours |
Wet Extended Detention Basin ** | 24 hours | Bio retention Cells | 40 hours |
Constructed Wetlands+ | 24 hours | Sand & Other Media Filters | 40 hours |
Infiltration Basins^ | 24-48 hours | Enhanced Water Quality Swales | 24 hours |
Pocket Wetlands# | 24 hours | ||
Vegetated Filter Strips | 24 hours | ||
* Dry basins must include forebay and micropool each sized at 10% of the WQv
** Provide both a permanent pool and an EDv above the permanent pool, each sized at 0.75 WQv + Extended detention shall be provided for the full WQv above the permanent water pool.
^ The WQv shall completely infiltrate within 48 hours so there is no standing or residual water in the BMP.
# Pocket wetlands must have a wet pool equal to the WQv, with 25% of the WQv in a pool and 75% in marshes. The EDv above the permanent pool must be equal to the WQv.
G. The owner may request approval from the Community Engineer to use alternative structural Post-Construction BMPs if the owner can demonstrate, in a way that is acceptable to Ohio EPA rules and regulations, that the alternative BMPs are equivalent in effectiveness to those listed in Table 2 above. The use of alternative or vender supplied Post-Construction BMPs should be limited to redevelopment projects where justification is provided that the traditional BMPs in Table 2 are technically and economically infeasible.
H. Construction activities shall be exempt from this condition if it can be demonstrated that the WQv is provided within an existing structural Post-Construction BMP that is part of a larger common plan of development or sale or if structural Post-Construction BMPs are addressed in a regional or local storm water management plan. A municipally operated regional storm water BMP can be used as a post-construction BMP provided that the BMP can detain the WQv from the entire drainage area and release it over a 24 hour period upon written permission from the Community Engineer.
I. For redevelopment projects (i.e., developments on previously developed property), Post-Construction practices shall either ensure a 20 percent net reduction of the site impervious area, provide for treatment of at least 20 percent of the WQv, or a combination of the two. Where projects are a combination of new development and redevelopment, the total WQv that must be treated shall be calculated by a weighted average based on acreage, with the new development at 100 per cent WQv and redevelopment at 20 percent WQv.
J. Site Description:
1. The prior land uses of the site
2. The nature and type of construction activity (e.g., low density residential, shopping mall, highway, etc.)
3. 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. Amount of the impervious area and percent imperviousness created by the construction activity
5. 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.
K. A vicinity sketch locating:
1. The development area
2. The larger common plan of development or sale
3. All pertinent surrounding natural features within 200 feet of the development site including, but not limited to:
4. Water resources such as wetlands, springs, lakes, ponds, rivers and streams (including intermittent streams with a defined bed and bank)
5. Conservation Easements
6. Other sensitive natural resources and areas receiving runoff from the development
L. The existing and proposed topography shown in the appropriate contour intervals as determined by the community engineer (generally one-foot contours are used).
M. 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.
N. Existing and proposed watershed boundary lines, direction of flow and watershed acreage.
O. The person or entity responsible for continued maintenance of all permanent vegetative and/or mechanical Post-Construction water quality conservation practices (BMPs).
P. The location of any existing or planned riparian and/or wetland setback areas on the property.
(Ord. 2013-41. Passed 9-24-13.)
Future access to all permanent vegetative and/or mechanical Post-Construction water quality conservation practices (BMPs) and other areas, as required by the Community Engineer, shall be secured by means of perpetual easements.
(a) The easements shall be recorded in the name of the Community and, in single-family residential developments, the homeowners association. Recorded easements must provide for community access.
(b) Such easements shall be not less than twenty-five (25) feet in width, in addition to the width of the ditch, channel, or other facility it is to serve. Further, an easement of this type shall be provided on one (1) side of the flood control or storm drainage ditch, channel, or similar-type facility.
(c) Access along the initial drainage system shall be by means of easements. Such easements shall be not less than twenty-five (25) feet in width, with a minimum ten (10) foot width on either side of the centerline.
(d) Access adjacent to storage facilities shall consist of a twenty-five (25) foot easement in the case of detention (dry) basins, and a twenty-five (25) foot easement with a twenty-five 25 foot level bench in the case of retention (wet) basins, measured from the top of the bank, and shall include the storage facility itself.
(e) Easements for the emergency flow ways shall be a minimum of twenty-five (25) feet in width, or larger if required by the Community Engineer.
(f) Flood control or storm drainage easements containing underground facilities shall have a minimum width of twenty-five (25) feet.
(g) The easements shall be restricted against the planting within said easement of trees, shrubbery or plantings with woody growth characteristics, and against the construction therein of buildings, accessory buildings, fences, walls or any other obstructions to the free flow of storm water and the movement of inspectors and maintenance equipment and also restricted against the changing of final grade from that described by the grading plan.
(Ord. 2013-41. Passed 9-24-13.)
Any portion of the permanent Post-Construction water quality management systems, including on-site and off-site treatment/storage facilities that are constructed by the owner, will be continuously maintained into perpetuity.
(a) Detail drawings and maintenance plans must be provided for all Post-Construction Best Management Practices (BMPs).
(b) Maintenance plans must ensure that pollutants collected within structural Post-Construction BMP practices are disposed of in accordance with local, state and federal guidelines.
(c) Maintenance plans shall be provided by the permittee to both the Community Engineer and the Post- Construction operator of the BMP (including homeowner associations) upon completion of construction activities and prior to the Community Engineer giving final approval for the completed construction.
(d) Single-Family Residential Developments: A Homeowners' Association shall be created and placed in title of the affected lands and shall be continuously responsible for Post-Construction maintenance and inspections into perpetuity unless such maintenance and inspections become officially accepted by the Community.
(e) Multi-Family, Commercial and Industrial Developments: The plans will clearly state that the owner of the property shall be continuously responsible for Post-Construction maintenance and inspections into perpetuity unless such maintenance and inspections become officially accepted by the Community.
(f) Maintenance Design: Low maintenance requirements are a priority in the design and construction of all facilities. Multi-use facilities incorporating assets such as aesthetics and recreation may be incorporated into the design of the drainage facilities. All permanent drainage, soil erosion, sediment control, water quality management systems and BMPs, including on-site and off-site structures and vegetation that are constructed or planted, must be inspected and maintained into perpetuity by the responsible party designated in the plans and the requirements of this ordinance. Inspections and maintenance will be incorporated periodically throughout the year to ensure that the facilities are properly operational.
(g) Perpetual Maintenance Inspections: One (1) inspection with a written report will be performed each year. The written report will be given to the Community Engineer by May 1 of each and every year after the Best Management Practice (BMP) has been completed.
(1) Structures that require a permit from the Ohio Division of Water: A written and stamped report from a professional engineer on the status of all structural BMPs that require a permit from the Ohio Department of Natural Resources (ODNR) Division of Water. This applies to all BMPs that require a permit either at the time of construction or fall under the jurisdiction of ODNR Division of Water at any time after construction is completed.
(2) Easements: A written report from an inspector on the status of all storm water management easements for each project shall be submitted to the Community Engineer by May 1 of each year into perpetuity. These reports will document if restricted plantings, fences and structures are on the easement and will identify the location of the noted easement restriction violations.
(3) Best Management Practices (BMPs) that do not have a high risk for loss of life, bodily injury, or damage to structures or infrastructure related to imminent failure as determined by the Community Engineer: A written and stamped report from a professional engineer, landscape architect or Certified Professional In Erosion and Sediment Control (CPESC) on the status of permanent soil erosion, sediment control, water quality management systems and the status of the related easements shall be submitted to the Community Engineer by May 1 of each year into perpetuity.
(4) BMPs that have a potential loss of Life: A written and stamped report covering the status of all BMPs that have a potential for loss of life, bodily injury, or damage to structures or infrastructure will be prepared by a professional engineer or other individual possessing a valid state license that authorizes them to design the same type of BMP for construction.
(Ord. 2013-41. Passed 9-23-14.)
In order to control pollution of water resources, the owner or person responsible for the development area shall use conservation planning and practices to maintain the level of conservation established in the following standards.
(a) Standards and Specifications: Post-Construction runoff practices used to satisfy these standards shall meet the standards and specifications in the current edition of the Rainwater and Land Development manual, NRCS Field Office Technical Guide for the local county, or the Ohio EPA, which ever is most stringent. The construction of new roads and roadway improvement projects by public entities shall implement Post-Construction BMPs in compliance with the current version of the Ohio Department of Transportation's Location and Design Manual, Volume Two: Drainage Design that has been accepted by Ohio EPA.
(b) Water Quality Basins:
(1) Pool Geometry: The minimum length-to-width ratio for the pond is 3:1 (the length will be three (3) times the width).
(2) Riser in Embankment: The riser shall be located within the embankment for purposes of maintenance access. Access to the riser will be by manholes.
(3) Water Drains: Each retention basin shall have a drainpipe that can completely drain the pond. The drain shall have an elbow within the pond to prevent sediment deposition from plugging the drain.
(4) Adjustable Gate Valves: Both the Water Quality and the Storm Water Management Basin drains shall have adjustable gate valves. Valves shall be located inside of the riser at a point where they will remain dry and can be operated in a safe and convenient manner. During the annual inspections the valves shall be fully opened and closed at least once, and the certifying official shall attest to this on the inspection form. To prevent vandalism, the handwheel shall be chained to a ringbolt or manhole step.
(5) Principal Spillway: Each principal spillway shall be designed in accordance with the Natural Resources Conservation Service (NRCS) standards and specifications for the office serving the local county. Each principal spillway shall have the capacity to pass the 100 year design storm flows. The inlet or riser size for the pipe drops shall be designed so that the flow through the structure goes from weir flow control to pipe flow control without going into orifice control in the riser. The crest elevation of the primary spillway shall be no less than one foot below the emergency spillway crest. Premium joint pipe is required and a removable trash rack shall be installed at each location. Anti-seep collars shall be provided for all pipe conduits through an embankment.
(6) Emergency Spillway: An emergency spillway shall be provided on each Water Quality and Storm Water Management basin. Emergency spillways shall convey flood flows safely past the embankment, and shall be designed in accordance with NRCS standards and specifications for the office serving the local county. Emergency spillways shall have a 100-year design storm capacity unless exempted in writing by the Community Engineer.
(7) Embankments: Each dam embankment shall be designed in accordance with the NRCS standards and specifications for the office serving the county that the project is located in. Anti-seep collars shall be provided for all pipe conduits through an embankment.
(8) Safety Features:
A. The primary spillway opening shall not permit access to the public and other non-maintenance personnel.
B. The perimeter of all water pool areas that are deeper than three (3) feet shall be surrounded by benches that meet the following:
1. A safety bench, with a maximum slope of 3%, which extends outward, on dry land, from the shoreline. This bench will be a minimum of 25 feet wide to provide for the safety of individuals and maintenance vehicles that are adjacent to the water pool. The safety bench may be landscaped, without the use of structures, to prevent access to the water pool.
2. Side slopes between the safety bench and the aquatic bench shall not be steeper than 3:1 (3 feet horizontal for every 1 foot vertical).
3. An aquatic bench that extends inward from the shoreline far enough to ensure public safety and has a maximum depth of 15 inches below the normal water surface elevations. The aquatic bench may be landscaped to prevent access to the deeper water pool. The aquatic bench may also be incorporated into the Post-Construction Water Quality Plan.
4. Side slopes beyond the aquatic bench and below the permanent water level shall not be steeper than 2:1 (2 feet horizontal for every 1 foot vertical).
5. The contours of the pond will be designed and managed to eliminate drop-offs and other hazards. Side slopes getting to the pond shall not exceed 3:1 and shall terminate on a safety bench.
(9) Water Quality Basin: If a Water Quality Basin is needed and cannot be incorporated into an existing or planned Detention or Retention Basin then a separate Water Quality Basin will need to be planned, designed, constructed and maintained into perpetuity.
(10) Water Quality Basins will not be constructed in any permanent or intermittent stream channel.
(11) Flexibility: These standards are general guidelines and shall not limit the right of the Community Engineer to impose at any time additional and/or more stringent requirements nor shall the standards limit the right of the Community Engineer to waive, in writing, individual requirements.
(12) If the Community Engineer waives, in writing, individual requirements the owner will provide the Community Engineer with the information and documentation required to assure Ohio EPA that the waived requirement will not degrade water quality.
(Ord. 2013-41. Passed 9-24-13.)
Sites that have been previously developed where no Post-Construction BMPs were installed shall either ensure a 20 percent net reduction of the site impervious area, provide for treatment of at least 20 percent of the WQv, or a combination of the two. A one-for-one credit towards the 20 percent net reduction of impervious area can be obtained through the use of pervious pavement and/or green roofs. Where projects are a combination of new development and redevelopment, the total WQv that must be treated shall be calculated by a weighted average based on acreage, with new development at 100 percent and redevelopment at 20 percent WQv.
(Ord. 2013-41. Passed 9-24-13.)
Where the Community Engineer determines that site constraints exist in a manner that compromises the intent of this ordinance to improve the management of storm water runoff as established in this ordinance, practical alternatives may be used to result in an improvement of water quality and/or a reduction of storm water runoff. Such alternatives must be in keeping with the intent and likely cost of those measures that would otherwise be required to meet the objectives of this section. All practical alternatives shall be implemented within the drainage area of the proposed development project unless specifically authorized in writing by the community engineer.
(a) Implementation of Off-site Storm Water Management Practices: The use of any off-site Post- Construction BMPs requires written approval from Ohio EPA and this approval must be received prior to design approval and/or issuance of any building permits. Practical alternatives to be considered include:
(1) Retrofitting of an existing storm water management practice.
(2) Watershed or stream restoration.
(3) Fees paid in an amount specified by the Community Engineer. The Community shall apply these fees to storm water management practices that improve the existing water quality.
(b) Use of Alternative Post-Construction BMPs: Permitees must supply written approval from Ohio EPA to use Post-Construction BMPs that have been demonstrated to be equivalent to the effectiveness of those listed in Table 2 above. Approval from Ohio EPA must be received prior to design approval and/or issuance of any building permits.
(c) Other practices approved by the Community Engineer in keeping with the intent of this section. (Ord. 2013-41. Passed 9-24-13.)
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