Surface Water Discharge Permitting (NPDES)

MassDEP and US EPA administer surface water discharge permits in Massachusetts.

Although jointly administered by EPA and MassDEP in the past, as of June 20, 2020, the National Pollutant Discharge Elimination System (NPDES) permit program is administered solely by the US EPA. MassDEP administers a parallel surface water discharge permitting program. Both programs control water pollution​ by regulating point sources that discharge pollutants to surface waters.

Table of Contents

State-specific Discharge Reporting

Regular filing of monitoring reports is a required element of a National Pollutant Discharge Elimination System (NPDES) permit.

Surface Water Discharge General Permits

For the most part, general permits are administered by EPA, require submission of a Notice of Intent (NOI) to EPA, and do not require an application to MassDEP. However, there are some circumstances that require submittal to both MassDEP and EPA. The following situations require applicants to submit a MassDEP transmittal form, a copy of the EPA’s NOI, payment (unless exempt), and any other required submittals to MassDEP:

  • Construction General Permit (CGP) with discharge to Outstanding Resource Waters (ORW);
  • Massachusetts Small Municipal Separate Storm Sewer Systems (MS4) Permit;
  • Publicly Owned Treatment Works General Permit (POTW GP);
  • Potable Water Treatment Facilities General Permit (PWTF GP) for first time applicants that also discharge to an ORW and High Quality Waters; 
  • Remediation General Permit (RGP) discharges from non-MCP sites;
  • Hydroelectric Generating Facilities General Permit (Hydro GP) with discharge to ORW waters.

Additional Resources

Surface Water Discharge Individual Permits

Individual permits are those not covered under a General Permit, for both industrial and non-industrial discharges.

Draft Individual Permits and Associated Documents

Final Individual Permits and Associated Documents

Additional Resources

NPDES Authorization

MassDEP is currently not authorized by US EPA to administer the NPDES program. MassDEP has taken some initial steps to explore the possibility of obtaining authorization in the future.

Additional Resources

NPDES Regulations

Additional Resources



Remediation 617-835-6693
Stormwater 617-556-1157
All other General Permits 617-654-6536


Contact for POTWs
205 Lowell Street
Wilmington, MA 01887
Contacts for PWTF, Remediation, Stormwater, and all other General Permits
100 Cambridge Street
8th floor
Boston, MA 02108

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