Connecticut Stream Flow Standards and Regulations

Final SF Class Map

  Map of Final Adopted Stream Flow Classifications  


Background 

In 2005, the Connecticut General Assembly passed Public Act 05-142 (CGS Section 26-141a and b) which required the Department of Energy and Environmental Protection (DEEP) to work with the Department of Public Health and stakeholders to update standards for maintaining minimum flows in rivers and streams. The act required these standards to balance river and stream ecology, wildlife, and recreation while providing for public health, flood control, industry, public utilities, water supply, public safety, agriculture, and other lawful uses of water.   

The Stream Flow Standards and Regulations were adopted on December 12, 2011. The process of classifying the streams and rivers of the State began with the Southeast Coastal, Pawcatuck, and Thames basins and were finalized on October 7, 2014. Streamflow classifications for the South Central Coastal basin were finalized on September 6, 2016. Streamflow classifications for the Connecticut River basin were finalized on February 20, 2018. Streamflow classifications for the Housatonic, Hudson, and Southwest basins were finalized on March 26, 2019. Classifications for all streams across the state are now complete.

Streamflow releases begin 10 years after streams have been classified. Therefore, streamflow releases begin on October 7, 2024, for dams located within the Southeast Coastal, Pawcatuck, and Thames basins; September 6, 2026, for dams located within the South Central Coastal basin; February 20, 2028, for dams located within the Connecticut River basin; and March 26, 2029, for dams located within the Housatonic, Hudson, and Southwest Coastal basins.


Additional Information:

Summary of Stream Flow Regulations

Stream Flow Classification Process

Frequently Asked Questions

History of Regulation Development

Stream Flow Data Links and Background Documents

Resources for Dam Owners Required to Make Streamflow Releases:

Dam owners that are required to make streamflow releases must submit an annual report to DEEP by March 31st of each year. Please review the instructions provided in the link below.

Instructions for submitting annual streamflow release data

Excel template required for annual submittal

Link to Survey123 reporting form


Initial Reporting - Stream Flow Reporting Form for Dams

If you are a dam owner and have not yet submitted an initial Stream Flow Reporting Form for Dams, please review the instructions below.

Owners or operators of certain dams located throughout the state MAY BE required to  submit an initial reporting form to the Department of Energy and Environmental Protection (DEEP) under the Stream Flow Standards and Regulations (ยง26-141b-7(a) of the Regulations of Connecticut State Agencies).  There are several due dates based on the location of the dam (see table below).

Significant Dates for Streamflow Release Requirements
 Basin(s) Classifications Published: Initial Reporting Form Due: Release Plan Due: Releases Begin:
 Southeast Coastal, Pawcatuck, and Thames River Basins October 7, 2014 October 7, 2015 October 7, 2023 October 7, 2024
South Central Coastal Basin September 6, 2016 September 6, 2017 September 6, 2025 September 6, 2026
Connecticut River Basin February 20, 2018 February 20, 2019 February 20, 2027 February 20, 2028
Housatonic, Hudson, and Southwestern Coastal Basins March 26, 2019 March 26, 2020 March 26, 2028  March 26, 2029
Only owners or operators of certain dams are required to submit the Stream Flow Reporting Form for Dams, as follows:

  • owners or operators of dams that will be required to make releases from the dam in accordance with the regulations (these are primarily large impoundments with consumptive withdrawals, like drinking water supply reservoirs); and
  • certain owners or operators for which submission of the form is a provision of exemption from making releases (primarily water utilities, golf courses and recreational lake dam owners).

DEEP strongly encourages all owners or operators of dams to review the Stream Flow Reporting Form for Dams. The form takes owners or operators of dams through the exemptions and what (if anything) is required for each. You may wish to begin by reviewing Part III, starting on page 3 of the Stream Flow Reporting Form for Dams, to determine if you meet any of the exemptions and if submission of the form is required before filling out the Stream Flow Reporting Form for Dams in its entirety.

Stream Flow Reporting Form for Dams (Word / PDF
Guidance for De Minimus Demonstration 

Please review the Stream Flow Reporting Form for Dams to determine whether your site is subject to reporting requirements if you have not done so already.

Questions can be directed to DEEP at (860) 424-3020 or deep.streamflowclass@ct.gov.


Contact Information:

If you have questions, or for further information on the program, please contact us at:

Connecticut Department of Energy and Environmental Protection
Bureau of Water Protection and Land Reuse 
Water Planning & Management Division
79 Elm Street
Hartford, CT 06106-5127

Phone: (860) 424-3020
Email: deep.streamflowclass@ct.gov
Fax: (860) 424-4055
Web: www.ct.gov/deep/streamflow

Content last updated on February 28, 2024