Stormwater Management Program (SWMP)

NPDES General Permit for Stormwater Discharges

The 2016 NPDES General Permit for Stormwater Discharges from Small Municipal Separate Storm Sewer Systems in Massachusetts (MS4 General Permit) is a jointly issued EPA-MassDEP permit. The Town submitted a Notice of Intent (NOI) for coverage under this MS4 General Permit and received authorization by EPA and MassDEP on March 5, 2019. The authorization allows the Town to discharge stormwater from its MS4 in accordance with the applicable terms and conditions of the MS4 General Permit.

Stormwater Management Program (SWMP)

To meet the terms and conditions of the MS4 General Permit, the Town has developed a stormwater management program (SWMP). The SWMP has been designed, to the maximum extent practicable, to reduce the discharge of pollutants from Belmont’s storm sewer system; to protect water quality, and to satisfy the water quality requirements of the Clean Water Act. The SWMP identifies Best Management Practices (BMPs) with measurable goals to address each of the six minimum control measures established by EPA. The minimum control measures are as follows:

  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 Construction and Redevelopment
  6. Pollution Prevention and Good Housekeeping in Municipal Operations

The Town is subject to additional requirements of Appendix F and H of the MS4 Permit for areas that discharge to waterbodies with approved Total Maximum Daily Loads (TMDLs) and certain waterbody impairments as identified in the MS4 Permit.

1 - Public Education and Outreach

The Town distributes educational stormwater flyers and brochures on a quarterly basis with utility bills. The information is also posted on the Town Hall bulletin boards and provided at the following links:

2 - Public Involvement and Participation

The Town’s SWMP is updated annually and available for public review and comment on a rolling basis.

3 - Illicit Discharge Detection and Elimination (IDDE) Program

The Town has developed and implemented an Illicit Discharge Detection and Elimination (IDDE) Program to systematically identify and eliminate illicit sources of non-stormwater discharges to its municipal separate storm sewer system and implement procedures to prevent and eliminate such discharges. The Town’s IDDE Plan was most recently updated in 2023 and is provided as Appendix E to the SWMP.

4 and 5 - Construction Stormwater Management and Post Construction Stormwater Management

The Town’s Stormwater Management and Erosion Control Bylaw and associated regulations aim to protect, maintain, and enhance the public safety, environment, health, and general welfare by establishing minimum requirements and procedures to manage stormwater runoff.

6 - Pollution Prevention and Good Housekeeping

The Town has developed operation and maintenance (O&M) procedures and Stormwater Pollution Prevention Plans (SWPPPs) to prevent and reduce pollutant runoff and protect water quality from Town-owned properties and operations.

Draft Phase I Phosphorus Control Plan (PCP)

The Town has developed a Draft Phase I Phosphorus Control Plan (PCP) for the Charles River watershed. This effort was undertaken to comply with Appendix F of the Town’s NPDES Permit for MS4 stormwater discharges, which is administered by the EPA. The NPDES Permit requires that the Town reduce its phosphorus load within the Charles River watershed by 52% (231 lb/year) by the Year 2038. The Draft Phase I PCP outlines a plan to achieve an interim milestone of 58 lb/year by the Year 2028. Phosphorus reduction will be achieved through existing and proposed stormwater best management practices (BMPs) within the Charles River watershed.

Actions for Water Quality Limited Waterbodies

Waterbodies with impairments triggering requirements of Appendix H of the MS4 Permit include Little River, Beaver Brook, and Spy Pond.

Phosphorous Source Identification Report (link coming soon)

2016 MS4 Permit Annual Reports

Previous MS4 Permit Documents

EPA and DEP Stormwater Links

Other Useful Links

Staff Contacts

Name Title Phone
Glenn R. Clancy, P.E. Town Engineer (617) 993-2665