DEEP: Municipal Stormwater

Municipal Stormwater
The General Permit for the Discharge of Stormwater from Small Municipal Separate Storm Sewer Systems (MS4 General Permit) is the product of a mandate by the U.S. Environmental Protection Agency (USEPA) as part of its Stormwater Phase II rules in 1999.  This general permit requires each municipality to take steps to keep the stormwater entering its storm sewer systems clean before that stormwater enters water bodies. One important element of this permit is the requirement that towns implement public education programs to make residents aware that stormwater pollutants emanate from many of their everyday living activities, and to inform them of steps they can take to reduce pollutants in stormwater runoff.
New MS4 General Permit:  Effective Date July 1, 2017 

Please be aware that there is an error in Section 6(j)(2) of the MS4 general permit on page 45 of 50. THE ANNUAL REPORT FOR 2017 IS DUE ON APRIL 1, 2018.

The new, modified MS4 General Permit is available below followed by the Registration Form, MS4 Town Permit Numbers, MS4 Best Management Practices, a Fact Sheet, DEEP Response to Comments, the MS4 Hearing Notice of Termination, and a marked-up version comparing the original July 8, 2014 draft MS4 General Permit and the January 20, 2016 new, modified MS4 General Permit.  All existing permittees and new permittees (8 new towns plus state and federal institutions) were required to prepare and submit a new registration and Stormwater Management Plan by April 1, 2017. Coverage under this new MS4 permit became effective on July 1, 2017.
Draft DOT Separate Storm Sewer System General Permit  
Town by Town Water Quality Factsheets
The factsheets below provide a variety of water quality data in various formats for every city, town, or borough in Connecticut.
Related Information
Content Last Updated December, 2017