City of New London
The City of New London has been issued a "General Permit for the Discharge of Stormwater from Small Municipal Separate Storm Sewer Systems" by Connecticut Department of Energy & Environmental Protection (CTDEEP). The permit is issued to ensure the City of New London is compliant with the requirements of EPA’s Clean Water Act (CWA) for municipalities and the developed areas within them.
The City of New London has created a Stormwater Management Plan, and prepares an annual report to be submitted to CT DEEP to demonstrate compliance with the permit and stormwater management plan. There are six minimum control measures for the plan:
- Public Education and Outreach on Stormwater Impacts
- Public Involvement and Participation
- Illicit Discharge Detection and Elimination
- Construction Site Stormwater Runoff Control
- Post-construction Stormwater Management in New Development and Redevelopment
- Pollution Prevention and Good Housekeeping for Municipal Operations
The annual report, submitted July 16, 2014, highlights each of these measures and explains what the City has been doing for each minimum measure. At this time the city of New London does not have an ordinance for the discharge of stormwater, but zoning regulations and the stormwater plan are the mechanisms that drive compliance with the permit. Developed areas that disturb more than or equal to 1 acre are required to have stormwater controls in place, and the property owner is responsible for an adequate long-term operations and maintenance plan for the BMPs installed onsite.
ZONING REGULATIONS OF THE CITY OF NEW LONDON
ARTICLE VI – SUPPLEMENTARY REGULATIONS
AMENDED TO SEPTEMBER 15, 2014
C. Design, Layout and Location
Drainage - In addition to the requirements of other sections of these regulations, the use of on-site natural filtration functions is encouraged as part of currently accepted Best Management Practices in the reduction of sediment and pollutants. Additionally; drainage shall not be directly channeled to wetlands or watercourses through new piping, flow though natural existing drainage systems shall be maintained as much as possible, and shall not result in a net increase of runoff from the site for the 25-year storm. Also, for previously undeveloped sites, the stormwater management system shall include the retention and filtration of the first inch of runoff from impervious surfaces (excluding roofs).
20) Stormwater Drainage
a) Parking areas shall be graded and drained to dispose of all surface water in accordance with sound engineering principles.
b) No storm water drainage shall be allowed to cross any sidewalk area or public streets.
c) Drainage shall be designed by a professional engineer licensed in the State of Connecticut.
d) The commission shall require that a stormwater management plan is submitted for all proposed parking lots consisting of twenty-five (25) or more parking spaces. However, the Commission may require a stormwater management plan for any proposal if it determines that the site disturbance and proposed use may cause significant nonpoint source pollution. The stormwater management plan shall provide, but not be limited to at a minimum the following information: (The City’s Office of Development and Planning (ODP) has been charged with the responsibility to prepare a recommended format for stormwater management plan submissions to the Commission under these regulations. All applicants are encouraged to consult with ODP staff prior to application submission.)
- Soil characteristics including soil types, hydrologic soil group, and depth to bedrock and groundwater where necessary.
- DEP ground/surface water quality classification of the site.
- Location and description of all proposed best management practices (BMPs) both for construction activities and post-construction long-term nonpoint source pollution control.
- Proposed maintenance and operation manual or schedule for any stormwater control methods.
- Hydrologic analysis and calculations of stormwater runoff rates and water quality pollutant concentrations including suspended solids removal rates for pre and post development.
- To the extent practicable, maintain post-development peak runoff rate and average volume at levels that are similar to pre-development levels and reduces post-development average annual total suspended solid (TSS) loads by 80%.
e) Stormwater management systems shall be designed and maintained to manage site runoff in order to prevent flooding, control peak discharges where required, and maximize retention and water quality treatment on-site.
f) On proposed sites with discharges of stormwater within five-hundred (500) feet of coastal waters, the stormwater management system shall be designed to retain and treat the volume generated by the first one (1) inch of rainfall unless a demonstration can be made that specific site constraints prevent meeting this goal. In such case, the stormwater management system should be designed to retain and treat the maximum amount that is technically feasible.
Inland Wetlands & Watercourses Regulations of the City of New London – Amended January 23, 2012
Any development activity occurring in this area is subject to more stringent standards. The map of regulated areas delineates the general location and boundaries of inland wetlands and the general location of watercourses. The link to these regulations is at the bottom of the page.
New London Stormwater Management Plan
This Stormwater Management Plan (SMP) was developed by the City of New London to protect water quality and reduce the discharge of pollutants from the municipality’s storm sewer system to the maximum extent practicable (MEP). This SMP addresses the requirements established by the CT Department of Energy and Environmental Protection’s (DEEP) General Permit for the Discharge of Stormwater from Small Municipal Separate Storm Sewer Systems (MS4 General Permit). This permit is the local enforcement mechanism of the U.S. Environmental Protection Agency’s (EPA) National Pollutant Discharge Elimination System (NPDES) Stormwater Phase II Rule. SMP Structure The plan outlines a program of best management practices (BMPs), measurable goals, responsible individuals or departments, and implementation schedules for the following six minimum control measures:
(1) Public education and outreach
(2) Public involvement and participation
(3) Illicit discharge detection and elimination
(4) Construction site stormwater runoff control
(5) Post-construction stormwater management in new development and redevelopment
(6) Pollution prevention/good housekeeping
In developing this legal authority, the City will consider the following watershed protection elements to manage the impacts of stormwater on receiving waters:
- Minimize the amount of impervious surfaces (roads, parking lots, roofs, etc.) within each municipality by minimizing the creation, extension, and widening of parking lots, roads, and associated development and encourage the use of Low Impact Development or green infrastructure practices.
- Preserve, protect, create and restore ecologically sensitive areas that provide water quality benefits and serve critical watershed functions. These areas may include, but are not limited to; riparian corridors, headwaters, floodplains and wetlands.
- Implement stormwater management practices that prevent or reduce thermal impacts to streams, including requiring vegetated buffers along waterways, and disconnecting discharges to surface waters from impervious surfaces such as parking lots.
- Seek to avoid or prevent hydromodification of streams and other water bodies caused by development, including roads, highways, and bridges.
- Implement standards to protect trees, and other vegetation with important evapotranspirative qualities.
- Implement policies to protect native soils, prevent topsoil stripping, and prevent compaction of soils.
- Coordinate with state or local health officials to ensure no interference with performance of on-site septic systems.
- Limit turf areas.
In addition, the City will review its current regulations - site planning requirements, zoning regulations, street design regulations, and infrastructure specifications with minimum size criteria for impervious cover (roads, parking lots, etc.) to identify and, where appropriate, reduce or eliminate existing regulatory barriers to implementation of LID and runoff reduction practices to the MEP.
5.2 Enforce LID/runoff reduction requirements for development and redevelopment projects
The City will enforce the LID and runoff reduction requirements defined in Section 5.1 for development and redevelopment projects.
5.3 Implement long-term maintenance plan for stormwater basins and treatment structures
The City will develop a maintenance plan for retention / detention ponds and stormwater treatment structures that it owns or over which it holds an easement or other authority and that are located in the City’s priority areas to ensure their long-term effectiveness. This plan will require an annual inspection of those retention / detention ponds and stormwater treatment structures and removal of accumulated sediment and pollutants in excess of 50% design capacity.
New London Stormwater Documents