(A) Water quality management.
(1) This section concerning post-construction water quality management is only applicable when the disturbed area is over one acre.
(2) If there is land disturbance over one acre, the permittee shall complete a permit application that includes a Post-Construction Water Quality Pollution Prevention Plan (P-SWPPP) to be completed, sealed and signed by a licensed professional engineer and/or land surveyor as appropriate and submitted to the city representative.
(B) Post-Construction Water Quality Pollution Prevention Plan. A SWQMP Permit requires a review and submittal of a Post-Construction Water Quality Pollution Prevention Plan (SWPPP). The Post-Construction SWPPP shall include the following information:
(1) A description of the proposed land use including amount of impervious area, directly connected impervious area and nature of the development;
(2) Location, dimensions, detailed specifications and construction details of all post-construction water quality Best Management Practices (BMPs), as defined in the city guidance documents;
(3) A sequence describing when each post-construction water quality BMP will be installed;
(4) A Long-Term Operation and Maintenance Agreement containing maintenance guidelines for all post-construction water quality measures to facilitate their proper long-term function. This Agreement shall be made available to future parties, including property owners, who will assume responsibility for the operation and maintenance of the post-construction water quality measures;
(5) The P-SWPPP shall include provisions for buffers:
(a) The waterway buffer will be used to define areas where land disturbance activities shall be permitted, but construction of any building or structure shall not be permitted.
(b) A waterway buffer shall be applied to all waterways serving more than 25 acres of tributary area or presented on a United States Geological Survey map as a blue line stream.
(c) The waterway buffer shall be defined as the greater of:
1. Area contained within a boundary established by the floodplain boundary as defined by FEMA or city master planning: or
2. Where a floodplain is not defined or calculated, the buffer will be 25-feet on each side from the top of waterway bank as defined by geomorphic shape (not by the current water surface elevation).
(e) The waterway buffer and floodplain may be used for application of water quality devices. This may only be permitted if erosion prevention and sediment control, water quality and cut-fill policies are adequately addressed as determined by the city according to the provisions of this subchapter.
(f) Exemptions are granted so long as erosion prevention and sediment control, water quality and cut-fill policies are adequately addressed. Exemptions shall be granted for:
(a) Roads and utilities crossing waterways;
(b) Pedestrian trails and walkways proximate to waterways; and
(c) Other exemptions may be made at the discretion of the city representative.
(6) A licensed professional engineer in the Commonwealth of Kentucky shall stamp all construction plans and long-term maintenance documentation. This shall include all proposed improvements or modifications to existing or new water quality infrastructure and other related improvements or modifications; and
(7) The city may require the posting of a maintenance bond to secure the structural integrity of the facilities as well as the functioning of the facilities in accordance with the approved Post-Construction SWPPP for a term of 24 months from the date of acceptance of dedication. An irrevocable letter of credit can be used as the financial assurance in lieu of a maintenance bond although the contribution shall be equivalent to the amount that would be estimated for the maintenance bond. The maintenance bond shall be calculated as 20% of the estimated construction cost and may be reduced to 10% after 12 months if there are no concerns by the city representative.
(C) BMP design requirements and criteria.
(1) The city reserves the right to develop or adopt other guidance documents to serve as design and implementation standards. Other guidance documents distributed by the city should be reviewed and considered when preparing the Post-Construction SWPPP. These documents may be applied as standards by which designs are to be prepared and controls implemented.
(2) The city shall have authority to implement this subchapter by appropriate regulations, guidance or other related materials. In this regard, technical, administrative or procedural matters may be modified as needed to meet the objectives defined herein, so long as such modifications as to technical, administrative or procedural matters are not contrary or beyond the intent of the objectives defined above.
(a) Regulations, guidance or other related materials that may be given authority by this subchapter may include, but are not limited to: Best Management Practice (BMP) manuals, design regulations and requirements, submittal checklists, review checklists, inspection checklists, certifications, water quality management manuals and operation and maintenance manuals;
(b) Materials may include information deemed appropriate by the city including guidance and specifications for the preparation of grading plans, selecting environmentally sound practices for managing water quality, minimum specifications and requirements, more complete definitions and performance standards;
(c) The above referenced documents may restrict or prevent the use of specific products, techniques or management practices (that are to be accepted by the public or are deemed to have a negative impact on public infrastructure or the MS4) that have been identified as unacceptable for performance, maintenance or other technically based reasons; and
(d) Documents referenced above may be updated periodically to reflect the most current and effective practices and shall be made available to the public. However, the failure to update the manual shall not relieve any applicant from the obligation to comply with this subchapter, and shall not prevent the city from imposing the most current and effective practices.
(3) The P-SWPPP shall include provisions for water quality BMPs functioning independently or in combination. Acceptable water quality BMPs shall be defined by policy and guidance documents as approved by the Water Quality Board.
(4) The P-SWPPP shall include provisions for water quality BMPs that are designed to achieve the following design/performance objectives:
(a) Reduce total suspended solids (TSS) from the first flush as defined by land use characteristics and contributing area; or, capture and treatment of at least one-half inch precipitation applied over the contributing area;
(b) Reduce or buffer increases in water runoff temperature caused by contact with impervious surfaces;
(c) Reduce or buffer increases in water runoff volume and flow rate caused by increases in directly connected impervious area and overall impervious area; and
(d) Water detention/retention facilities shall be designed to address the rate at which flow is released over the entire runoff discharge period and the volume of discharge over the critical design-storm period if defined by city water quality master plans. The outlet structure shall be designed as a v-notch weir or other multiple stage configurations capable of controlling the discharge rates for the first flush, two-, ten- and 25-year design-storm events. The outlet structure shall be designed to safely bypass the 100-year storm event.
(5) Soil bio-engineering, “green” and other “soft” slope and stream bank stabilization methods shall receive preference over rip rap, concrete and other hard armoring techniques.
(6) Retention supportive data must be submitted to justify the type of facility selected. If the facility is designed to retain (volume control) all or a significant portion of runoff (as opposed to temporarily detain), then appropriate soils analyses findings shall be submitted to the city. This submission shall also discuss the impacts the facility will have on local karst topography as found through a geotechnical investigation of the site. The facility may be designed to infiltrate runoff to groundwater rather than transmit it downstream under conditions up to a ten-year storm event. It must be able to bypass all other storms including 100-year event with a discharge rate equivalent to or less than pre-development conditions without negatively impacting the 100-year floodplain above or below the site. If data indicates that the facility cannot retain a significant portion of the runoff (95%), then the facility must be designed to detain runoff.
(7) If available, each P-SWPPP shall be evaluated for consistency with the Water Quality Master Plan or watershed study for the major watershed or watersheds within which the project site is located. The individual project evaluation will determine if water quantity and quality management practices can adequately serve the property and limit impacts to downstream public and private properties. The presence of a regional facility(s) will be considered in determining the extent to which water quantity and/or quality controls will be necessary.
(8) The city reserves the right to require superseding or additional treatment criteria or objectives for specific pollutant(s) as necessary to meet overall water quality management program objectives or directives under a watershed improvement or Total Maximum Daily Load (TDML) program as administered by the USEPA or Commonwealth of Kentucky.
(9) On-site BMP Coordination with regional BMPs.
(a) All properties are expected to implement on-site water quality control measures, but the extent of application may be reduced given the availability, proximity and nature of regional water quality BMPs.
(b) The extent and type of on-site water quality management practices implemented shall be proportionate to the land use, and proximity to regional water quality management practices.
(D) BMP ownership and easements.
(1) Any water management facility or BMP which services individual property owners shall be privately owned. General routine maintenance (controlling vegetative growth and removing debris) shall be provided by the owner(s). The owner shall maintain a perpetual, non-exclusive easement that allows for access for inspection and emergency maintenance by the city. The city has the right, but not the duty, to enter premises for emergency repairs.
(2) Any water quality management facility or BMP which services an individual residential subdivision in which the facility or BMP is within designated open areas or serves as an amenity with an established homeowners association shall be privately owned and maintained consistent with provisions of this subchapter. The owner shall maintain a perpetual, nonexclusive easement which allows access for inspection and emergency maintenance by the city. The city has the right, but not the duty, to enter premises for emergency repairs.
(3) Any water quality management facility or BMP which services commercial and industrial development shall be privately owned and maintained. The owner shall maintain a perpetual, nonexclusive easement which allows access for inspection and emergency maintenance by the city. The city has the right, but not the duty, to enter premises for emergency repairs.
(4) All regional water quality management control facilities proposed by the owners, if approved and accepted by the city for dedication as a public regional facility, shall be publicly owned and/or maintained. All other water quality management control facilities and BMPs shall be privately owned and/or maintained unless accepted for maintenance by the city.
(5) The city may require dedication of privately owned water quality facilities, which discharge to the city water quality system. This shall be at the approval of the City Council.
(E) Regional facilities management.
(1) The objective of a regional water quality management facility, pond or other device, is to address the water quality management concerns in a given watershed with greater economy and efficiency than possible through individual facilities. The intended result is fewer water quality management facilities to maintain in the affected watershed while sustaining efficiency.
(2) The city encourages regional water quantity and/or quality management practices, serving 25 to 250 acres of tributary area, which may be consistently and efficiently managed and maintained. These types of practices will be encouraged in order to replace or reduce the implementation of on-site water quantity and/or quality management practices, as determined to be appropriate by the city.
(3) Where a regional water quality management facility has been established by one or more local governments, or by an authority operating on behalf of one or more local governments, a development or property may participate in the program in lieu of runoff control required by this subchapter. This may be permitted provided that:
(a) Runoff from the development drains to an approved existing or proposed public regional water quality management facility that will be operational within one year;
(b) Participation in the form of contribution of funds, contribution of land, contribution of quality management facility construction work or a combination of these, the total value of which shall be in accordance with a fee schedule adopted by the city;
(c) The city finds that the water quality management plans are in compliance with all other applicable requirements and ordinances; and
(d) Each fiscal or in-kind contribution from a development owner participating in a regional water quality management facility shall be used for acquisition, design, construction or maintenance of one or more such facilities in the same watershed in which the development is located.
(4) Detention facilities may, and are encouraged, to be designed to serve multiple purposes. For example, runoff may be detained under wet-weather conditions, but also serve as common or recreational areas during dry-weather conditions. Where multi-purpose facilities are provided, or where flat grades or poorly draining soils are encountered, provisions for adequate low-flow water quality management system may be required. Where the retention/detention facility is planned to be used as a lake, pond or water quality management practice with a permanent pool, water budget calculations shall be performed and submitted to demonstrate that an adequate permanent pool depth is expected during dry summer months.
(F) Long-term operation and maintenance agreements.
(1) Long-term operation and maintenance agreements. Long-Term Operation and Maintenance Agreements shall include a maintenance plan for all water quality BMPs in new development or redevelopment that require more than general maintenance (e.g. periodic mowing).
(a) The plan will be developed to ensure that the water quality BMP(s) is (are) kept functional. The maintenance agreement will specify minimum operation and maintenance requirements and intervals to be performed by the property owner.
(b) The plan shall address schedules for inspections and techniques for operation and maintenance including vegetation clearing or mowing and removing accumulated trash, debris, sediment pollutants and other forms of pollution.
(c) The agreement shall be noted on the final plat with the appropriate notation on the particular lot(s).
(d) The agreement shall be included with property ownership title documents and shall be binding on the owner, its administrators, executors, assigns, heirs and any other successors in interest.
(e) The format for the Long-Term Operational and Maintenance Agreement shall be provided through example by the city, or through guidance documents.
(f) Care must be taken to ensure that any required facilities do not become nuisances or health hazards. Detention and retention facilities should be designed to require minimal maintenance, and maintenance expectations must be clearly stated in the Long-Term Operation and Maintenance Agreement.
(g) When a water quality BMP serves more than one parcel, a home or property owners’ association or binding contract for the purpose of operation and maintenance is required. The owners’ association shall be responsible for operation and maintenance as directed by this subchapter.
(2) Single entity ownership. Where the permanent water quality runoff control facilities are designed to manage runoff from property in a single entity ownership, the maintenance responsibility for the water quality control facilities shall be with the single entity owner.
(a) A SINGLE ENTITY shall be defined as an association, public or private corporation, partnership firm, trust, estate or any other legal entity allowed to own real estate exclusive of an individual lot owner.
(b) The stated responsibilities of the entity shall be documented in the Long-Term Operation and Maintenance Agreement. Terms including owning, operating and maintaining the facilities shall be submitted with plans in application for a SWQMP Permit for an adequacy determination. Approval of a SWQMP shall be conditioned upon the approval of these terms. These terms shall be in writing, shall be in recordable form and shall, in addition to any other terms deemed necessary by the city, contain a provision permitting inspection at any reasonable time by the city of all facilities deemed critical in the public welfare.
(c) Upon approval of the water quality BMPs by the city, the facility owner(s) shall demonstrate the ability to guarantee and apply the financial resources necessary for long-term maintenance requirements. The funding mechanism shall be in a form approved by the city. The city will only approve funding mechanism(s) for long-term maintenance responsibilities that can be demonstrated to be permanent or transferable to another entity with equivalent longevity.
(d) In the event that proposed funding is through an owners’ association, then it must be demonstrated that the association may not dissolve unless long-term operation and maintenance activities are accepted by another entity with equivalent longevity and adequate funding. Furthermore, the owners’ association’s responsibility must be stated in the association’s declaration, covenants or by-laws, as appropriate.
(e) Unless made specifically clear in the preliminary stages of the site design and construction plan review procedure, it will be assumed that all water detention, retention, treatment or storage facilities and/or devices shall be owned, operated and maintained by a single entity as defined above.
(3) City ownership. Where the city has accepted an offer of dedication of the permanent water quality BMPs, the city shall be responsible for operation and maintenance.
(Ord. 2009-1, passed 5-4-2009)