Legal Documents of Jefferson City

1. Adoption. The city adopts as its MS4 stormwater design and Best Management Practices (BMP) manuals for stormwater management, construction and permanent, the following publications, which are incorporated by reference in this ordinance as if fully set out herein:
   1. TDEC Erosion Prevention and Sediment Control Handbook; most current edition.
   2. The Tennessee Permanent Stormwater Management and Design Guidance Manual; most current edition.
   3. A collection of MS4 approved BMPs developed or collected by the MS4 that comply with the goals of the MS4 permit and/or the CGP.
2. The city's BMP manual(s) include a list of acceptable BMPs including the specific design performance criteria and operation and maintenance requirements for each stormwater practice. These include city approved BMPs for permanent stormwater management including green infrastructure BMPs.
3. The city manual(s) may be updated and expanded from time to time, at the discretion of the governing body of the city, upon the recommendation of the director of public works and utilities based on improvements in engineering, science, monitoring and local maintenance experience, or changes in federal or state law or regulation. Stormwater facilities that are designed, constructed and maintained in accordance with these BMP criteria will be presumed to meet the minimum water quality performance standards.

Land development. This section shall be applicable to all land development, including, but not limited to, site plan applications, subdivision applications, land disturbance applications and grading applications. These standards apply to any new development or redevelopment site that meets one (1) or more of the following criteria:

1. One (1) acre or more;
   1. New development that involves land development activities of one (1) acre or more;
   2. Redevelopment that involves other land development activity of one (1) acre or more;
2. Projects or developments of less than one (1) acre of total land disturbance may also be required to obtain authorization under this ordinance if:
   1. The director of public works and utilities has determined that the stormwater discharge from a site is causing, contributing to, or is likely to contribute to a violation of a state water quality standard;
   2. The Director of public works and utilities has determined that the stormwater discharge is, or is likely to be a significant contributor of pollutants to waters of the state;
   3. Changes in state or federal rules require sites of less than one (1) acre that are not part of a larger common plan of development or sale to obtain a stormwater permit;
   4. Any new development or redevelopment, regardless of size, that is defined by the director of public works and utilities to be a hotspot land use; or
   5. Minimum applicability criteria set forth in item (a) above if such activities are part of a larger common plan of development, even multiple, that is part of a separate and distinct land development activity that may take place at different times on different schedules.

Note: Any discharge of stormwater or other fluid to an improved sinkhole or other injection well, as defined, must be authorized by permit or rule as a Class V underground injection well under the provisions of Tennessee Department of Environment and Conservation (DEC) Rules, chapter 1200-4-6.

Submittal of a copy of the NOC, SWPPP and NOT to the local MS4. Permittees who discharge stormwater through an NPDES-permitted municipal separate storm sewer system (MS4) who are not exempted in section 1.4.5 (Permit Coverage through Qualifying Local Program) of the Construction General Permit (CGP) must provide proof of coverage under the Construction General Permit (CGP); submit a copy of the Stormwater Pollution Prevention Plan (SWPPP); and at project completion, a copy of the signed Notice of Termination (NOT) to the director of public works and utilities. Permitting status of all permittees covered (or previously covered) under this general permit as well as the most current list of all MS4 permits is available at the DEC's data viewer web site.

Copies of additional applicable local, state or federal permits (i.e.: ARAP, etc.) must also be provided upon request.

If requested, these permits must be provided before the issuance of any land disturbance permit or the equivalent.

1. Project description - Briefly describe the intended project and proposed land disturbing activity including number of units and structures to be constructed and infrastructure required.
2. A topographic map with contour intervals of five feet (5') or less showing present conditions and proposed contours resulting from land disturbing activity.
3. All existing drainage ways, including intermittent and wet-weather. Include any designated floodways or flood plains.
4. A general description of existing land cover. Individual trees and shrubs do not need to be identified.
5. Stands of existing trees as they are to be preserved upon project completion, specifying their general location on the property. Differentiation shall be made between existing trees to be preserved, trees to be removed and proposed planted trees. Tree protection measures must be identified, and the diameter of the area involved must also be identified on the plan and shown to scale. Information shall be supplied concerning the proposed destruction of exceptional and historic trees in setbacks and buffer strips, where they exist. Complete landscape plans may be submitted separately. The plan must include the sequence of implementation for tree protection measures.
6. Approximate limits of proposed clearing, grading and filling.
7. Approximate flows of existing storm water leaving any portion of the site.
8. A general description of existing soil types and characteristics and any anticipated soil erosion and sedimentation problems resulting from existing characteristics.
9. Location, size and layout of proposed stormwater and sedimentation control improvements.
10. Existing and proposed drainage network.
11. Proposed drain tile or waterway sizes.
12. Approximate flows leaving site after construction and incorporating water run-off mitigation measures. The evaluation must include projected effects on property adjoining the site and on existing drainage facilities and systems. The plan must address the adequacy of outfalls from the development: when water is concentrated, what is the capacity of waterways, if any, accepting stormwater off-site; and what measures, including infiltration, sheeting into buffers, etc., are going to be used to prevent the scouring of waterways and drainage areas off-site, etc.
13. The projected sequence of work represented by the grading, drainage and sedimentation and erosion control plans as related to other major items of construction, beginning with the initiation of excavation and including the construction of any sediment basins or retention/detention facilities or any other structural BMPs.
14. Specific remediation measures to prevent erosion and sedimentation run-off. Plans shall include detailed drawings of all control measures used; stabilization measures including vegetation and non-vegetation measures, both temporary and permanent, will be detailed. Detailed construction notes and a maintenance schedule shall be included for all control measures in the plan.
15. Specific details for: the construction of stabilized construction entrance/exits, concrete washouts, and sediment basins for controlling erosion; road access points; eliminating or keeping soil, sediment, and debris on streets and public ways at a level acceptable to the city. Soil, sediment, and debris brought onto streets and public ways must be removed by the end of the work day to the satisfaction of the city. Failure to remove the sediment, soil or debris shall be deemed a violation of this ordinance.
16. Proposed structures: location and identification of any proposed additional buildings, structures or development on the site.
17. A description of on-site measures to be taken to recharge surface water into the ground water system through runoff reduction practices.
18. Specific details for construction waste management. Construction site operators shall control waste such as discarded building materials, concrete truck washout, petroleum products and petroleum related products, chemicals, litter, and sanitary waste at the construction site that may cause adverse impacts to water quality. When the material is erodible, such as soil, the site must be treated as a construction site.

1. Site design standards for all new and redevelopment require, in combination or alone, management measures that are designed, built and maintained to infiltrate, evapotranspire, harvest and/or use, at a minimum, the first inch of every rainfall event preceded by seventy-two (72) hours of no measurable precipitation. This first inch of rainfall must be one hundred percent (100%) managed with no discharge to surface waters.
2. Limitations to the application of runoff reduction requirements include, but are not limited to:
   1. Where a potential for introducing pollutants into the groundwater exists, unless pretreatment is provided;
   2. Where pre-existing soil contamination is present in areas subject to contact with infiltrated runoff;
   3. Presence of sinkholes or other karst features.
3. Pre-development infiltrative capacity of soils at the site must be taken into account in selection of runoff reduction management measures.
4. Incentive standards for re-developed sites: a ten percent (10%) reduction in the volume of rainfall to be managed for any of the following types of development. Such credits are additive such that a maximum reduction of fifty percent (50%) of the standard in the paragraph above is possible for a project that meets all five (5) criteria:
   1. Redevelopment;
   2. Brownfield redevelopment;
   3. High density (>7 units per acre);
   4. Vertical density, (Floor to Area Ratio (FAR) of 2 or >18 units per acre); and
   5. Mixed use and transit oriented development (within one half (1/2) mile of transit).
5. For projects that cannot meet one hundred percent (100%) of the runoff reduction requirement unless subject to the incentive standards, the remainder of the stipulated amount of rainfall must be treated prior to discharge with a technology documented to remove eighty percent (80%) Total Suspended Solids (TSS) unless an alternative provided under this ordinance is approved. The treatment technology must be designed, installed and maintained to continue to meet this performance standard.
6. For projects that cannot meet one hundred percent (100%) of the runoff reduction requirements, the director of public works and utilities may allow runoff reduction measures to be implemented at another location within the same USGS twelve (12) digit Hydrologic Unit Code (HUC) as the original project. Off-site mitigation must be a minimum of one and one half (1.5) times the amount of water not managed on site. The off-site mitigation location (or alternative location outside the twelve (12) digit HUC) and runoff reduction measures must be approved by the director of public works and utilities. The director of public works and utilities shall identify priority areas within the watershed in which mitigation projects can be completed. The director of public works and utilities must create an inventory of appropriate mitigation projects, and develop appropriate institutional standards and management systems to value, evaluate and track transactions. Mitigation can be used for retrofit or redevelopment projects, but should be avoided in areas of new development.
7. To protect stream channels from degradation, specific channel protection criteria shall be provided as prescribed in the MS4 BMP manual.
8. Stormwater discharges to critical areas with sensitive resources (i.e., cold water fisheries, shellfish beds, swimming beaches, recharge areas, water supply reservoirs) may be subject to additional performance criteria, or may need to utilize or restrict certain stormwater management practices.
9. Stormwater discharges from hot spots may require the application of specific structural BMPs and pollution prevention practices. In addition, stormwater from a hot spot land use may not be infiltrated.
10. Prior to or during the site design process, applicants for land disturbance permits shall consult with the director of public works and utilities to determine if they are subject to additional storm water design requirements.
11. The calculations for determining peak flows as found in the MS4 BMP manual shall be used for sizing all stormwater facilities.

1. Stormwater designs shall meet the multi-stage storm frequency storage requirements as identified in the MS4 BMP manual.
2. If hydrologic or topographic conditions warrant greater control than that provided by the minimum control requirements, the director of public works and utilities may impose any and all additional requirements deemed necessary to control the volume, timing, and rate of runoff.

1. Topographic base map: topographic base map of the site which extends a minimum of one hundred feet (100') beyond the limits of the proposed development and indicates:
   1. Existing surface water drainage including streams, ponds, culverts, ditches, sink holes, wetlands; and the type, size, elevation, etc., of nearest upstream and downstream drainage structures;
   2. Current land use including all existing structures, locations of utilities, roads, and easements;
   3. All other existing significant natural and artificial features;
   4. Proposed land use with tabulation of the percentage of surface area to be adapted to various uses; drainage patterns; locations of utilities, roads and easements; the limits of clearing and grading.
2. Proposed structural and non-structural BMPs;
3. A written description of the site plan and justification of proposed changes in natural conditions may also be required;
4. Calculations: hydrologic and hydraulic design calculations for the pre-development and post-development conditions for the design storms specified in the MS4 BMP manual. These calculations must show that the proposed stormwater management measures are capable of controlling runoff from the site in compliance with this chapter and the guidelines of the MS4 BMP manual. Such calculations shall include:
   1. A description of the design storm frequency, duration, and intensity where applicable;
   2. Time of concentration;
   3. Soil curve numbers or runoff coefficients including assumed soil moisture conditions;
   4. Peak runoff rates and total runoff volumes for each watershed area;
   5. Infiltration rates, where applicable;
   6. Culvert, stormwater sewer, ditch and/or other stormwater conveyance capacities;
   7. Flow velocities;
   8. Data on the increase in rate and volume of runoff for the design storms referenced in the MS4 BMP manual; and
   9. Documentation of sources for all computation methods and field test results.
5. Soils information: If a stormwater management control measure depends on the hydrologic properties of soils (e.g., infiltration basins), then a soils report shall be submitted. The soils report shall be based on on-site boring logs or soil pit profiles and soil survey reports. The number and location of required soil borings or soil pits shall be determined based on what is needed to determine the suitability and distribution of soil types present at the location of the control measure.

1. Construction.
   1. Construction requires buffer zone widths of a minimum of thirty feet (30'). The thirty foot (30') criterion for the width of the buffer zone can be established on an average width basis. As long as the minimum width of the buffer zone is fifteen feet (15'). The buffer zone shall meet all the other applicable requirements of § 14-402(5) and (6).
   2. Construction on impaired or exceptional waters. The width of the buffer zone shall be a minimum of sixty feet (60'). The sixty feet (60') criterion for the width of the buffer zone can be established on an average basis at a project as long as the minimum width of the buffer is more than thirty feet (30') at any measured location. The buffer zone shall meet all the other applicable requirements of 14-402(5) and (6).
2. Permanent.
   1. More than one (1) square mile drainage area will require buffer zones of a minimum of sixty feet (60'). The sixty foot (60') criterion for the width of the buffer zone can be established on an average width basis, as long as the minimum width of the buffer zone is more than thirty feet (30') at any measured location.
   2. Less than one (1) square mile drainage area. Less than one (1) square mile drainage area will require buffer zones of a minimum of thirty feet (30'). The thirty foot (30') criterion for the width of the buffer zone can be established on an average width basis, as long as the minimum width of the buffer zone is more than thirty feet (30') at any measured location. The buffer zone shall meet all the other applicable requirements of § 14-402(5) and (6). (as added by Ord. #2016-06, June 2016, and amended by Ord. #2023-03, April 2023 Ch17_06-18-24)