Nonpoint Source (NPS) Pollution Management

Many activities associated with various land uses within Connecticut have the potential to contribute pollution to ground and surface water resources. Water pollution that is not concentrated within a drainage system, or discharged from a point, such as a pipe, is called nonpoint source pollution. Potential sources of Nonpoint Source Pollution include:
  • agriculture,
  • waste from domestic animals and wildlife,
  • malfunctioning septic systems,
  • runoff from impervious surfaces and managed turfgrass,
  • soil erosion,
  • atmospheric deposition,
  • marinas and boating activity,
  • and others. 
Pollutant levels, or loadings, from nonpoint sources can be increased by weather conditions which cause stormwater runoff or snowmelt. If pollutant concentrations from these nonpoint sources are high enough, uses of those surface or groundwaters for public water supplies, recreation, or aquatic life may become impaired. In Connecticut, stormwater pollution from urban areas that is collected in stormdrains, or that discharges from construction, commercial, or industrial sites, is regulated by stormwater general permits, so is technically considered point source pollution. More information on Stormwater Management and Permitting The Connecticut Department of Energy and Environmental Protection has worked to develop programs, technologies and legislation with both local and national significance that are protective of water resources, and has led a national pilot program to monitor nonpoint source pollution at residential development sites.

A significant component of Connecticut DEEP’s Nonpoint Source Management Program consists of implementing the EPA Clean Water Section 319 Program.  DEEP issues a Request for Proposals annually for 319 Nonpoint Source Projects.

Section 319 Nonpoint Source Grant Request for Proposals

CT DEEP's Watersheds Section publishes a Request for Proposals (RFP) annually based on funding provided by the U.S. Environmental Protection Agency. Through this competitive RFP process, CT DEEP provides grants for projects focused on addressing Nonpoint Source impacts in surface waters. Proposals may be submitted by any interested public or private organization, see the link above for more information.

 Additional Nonpoint Source Program Initiatives
GRTS: Grant Reporting and Tracking System

State grant recipients are required to report their progress annually in GRTS, including reductions of NPS pollutant loadings and improvements to water quality achieved by pollution control practices.  GRTS enables EPA and States to demonstrate the accomplishments achieved with the use of 319 grant funds.  The data entered into GRTS is used by EPA to respond to inquiries received from Congressional committees, the White House, and various constituent groups.

Grant recipients should fill out the GRTS Worksheet below, save it, and email it to your DEEP Project Manager. 
  • EPA GRTS Worksheet Mandated Elements for GRTS Projects - (XLS) form updated March 2015

Required "load reduction" calculations should be accomplished using the Pollution Load Estimation Tool (PLET) which can be found at: by selecting the Link to PLET under the Model Documentation header. The PLET replaces the former models used for these calculations, the STEPL and the Region 5 Load Estimation Spreadsheet. A PLET User’s Guide and Training Video are available on the EPA website.

EPA's GRTS Home has more information on GRTS.

Monitoring Data Submission - The Water Quality Portal

The Water Quality Portal (WQP) is a searchable database sponsored by the United States Geological Survey, the Environmental Protection Agency, and the National Water Quality Monitoring Council. The WQP contains data collected by over 400 state, federal, tribal, and local agencies. Monitoring data collected using State grant monies are required to be submitted to the Water Quality Portal.

Grant recipients experienced in database entry can choose to upload data directly to the portal by registering for a Water Quality Exchange (WQX) account.  Others can request DEEP WQP data entry support by e-mailing the completed templates below to your DEEP Project Manager. Additional instructions will be provided upon receipt. 

WQX/WQP Monitoring Data Submission Templates:

DEEP's Watershed Management Program is actively involved in administering nonpoint source control grants and programs.  For further information, please contact



Content last updated December 12, 2023