NPDES Phase 2 - MS4 Stormwater Permitting

The Town of Stonington is required to develop and implement a new Stormwater Management Plan (SMP) under the revised General Permit for the Discharge of Stormwater from Small Municipal Separate Storm Sewer Systems (MS4 General Permit) issued by the CT Department of Energy and Environmental Protection.  The intent of the SMP is to develop strategies and Best Management Practices (BMPs) related to stormwater which, when implemented may reduce and/or eliminate pollutants that make their way into storm sewer systems and ultimately into the town's receiving water bodies. 

The SMP will outline a program specific to Stonington that is consistent with the general permit requirements.  Implementation of the plan will occur over a five year period beginning on the effective date of the permit, July 1, 2017.  Annual reports will be filed at the end of each year outlining the level of compliance with the SMP.  The new SMP, similar to the current plan, is organized into the following six minimum control measures with a significant emphasis moving forward, placed on locations with impaired water bodies and Directly Connected Impervious Areas exceeding 11%:

  1. Public Education and Outreach
  2. Public Participation
  3. Illicit Discharge Detection and Elimination (IDDE):
  4. Construction Site Stormwater Runoff Control
  5. Post-construction Stormwater Management
  6. Pollution Prevention and Good Housekeeping

The Engineering Department is responsible for general oversight and implementation of this plan.  Below is a list of pertinent links related to: CTDEEP MS4 General Permit, CTDEEP & EPA Websites, MS4 Annual Reports, and other Educational Resources.  This information is provided to increase the community's awareness of the negative impacts of pollutants in storm sewer systems, how they get there, and what the general public can do to assist in improving our water quality. 

State Map:


State & Federal Agency Links:


Educational Data:

Watershed Studies:


Town Stormwater Ordinances & Regulations:

Town of Stonington Stormwater Management Plan


Town of Stonington Annual MS4 Reports:


Stormwater Complaints:

If you would like to report an issue or comment on a Stormwater related topic such as: Illegal/illicit discharge connections, Municipal stormdrain maintenance & operation, Stormwater quality, Illegal dumping, Concerns about proposed and ongoing land disturbance and development activities, or just helpful tips for improved overall stormwater management, Please contact the Public Works/Engineering Department by filling out this form and mailing it to Town Hall attention Director of Public works, or you can fill it out online here. You may also call the Engineering Department at (860) 535-5076