NPDES / Stormwater Management Program

As part of the Environmental Protection Agency (EPA) National Pollutant Discharge Elimination System (NPDES) permitting program, the Town is required to take steps to reduce the impact of stormwater pollution. The Town of Watertown stormwater drainage system operates as a Municipal Separate Storm Sewer System (MS4) under this permit.

The Town’s program includes the following elements:

View Presentation to Public Works Subcommittee February 2016

2016 General Permit

The EPA issued a new, updated general permit effective July 1, 2018. This permit replaces the 2003 permit and contains updated and new requirements that the Town will have to meet. The entire contents of the permit are available at the EPA’s web-site.

September 2021:

View our Year 3 Annual Report here:  Annual Report

January 2021:

The Stormwater Advisory Committee reviewed and discussed the Town’s Stormwater Management Plan at its January 21, 2021 meeting. View the presentation here. Watch the full meeting here.

September 2020:

View our Year 2 Annual Report here: Annual Report

The Stormwater Management Plan has also been updated to reflect changes made to-date: Watertown Final SWMP - Sept 2020

February 2020:

DPW provided updates on implementation of Year 2 permit requirements to the Stormwater Advisory Committee at their February 19, 2020 meeting.

October 2019:

The Town submitted its annual report for year one to the EPA.

July 2019:

The final Stormwater Management Plan (SWMP) is available here:

Stormwater Management Plan - Final

May 2019:

The EPA reviewed the notice of intent and issued the town this authorization letter.

April 2019:

The Town is developing an updated stormwater management plan which outlines the steps the Town will take to comply with the new permit requirements in greater detail than in the Notice of Intent (NOI).

View the draft Stormwater Management Plan (SWMP):

Stormwater Management Plan

Stormwater Management Plan Appendices

View Stormwater Advisory Committee Presentation

Comments on the draft SWMP will be accepted through May 15, 2019. Please submit comments to When submitting comments please reference "Stormwater Management Plan" in subject line of email.  

October 2018:

On October 1, 2018, the Town submitted a Notice of Intent (NOI) for coverage under the 2016 permit. The NOI contains basic information about the Town’s stormwater system and a general outline of steps the Town will take to comply with the new permit requirements.

Previous Annual Reports

View Most Recent Report (PDF) | View Past Reports