Integrated Water Quality Report to Congress
Prepared Pursuant to Clean Water Act Sections 305(b) and 303(d)
The FINAL 2024 Integrated Water Quality Report and Response to Comments is now available.
Every two years (sometimes referred to as a cycle) Connecticut submits the Integrated Water Quality Report to Congress (IWQR). The report covers two sections of the Clean Water Act (CWA), 305 (b) and 303 (d).
Section 305(b) of the Federal Clean Water Act (CWA) requires each State to monitor, assess and report on the quality of its waters relative to designated uses established in accordance with the Connecticut Water Quality Standards.
Section 303(d) of the CWA requires each State to list waters not meeting water quality standards and prioritize those waters for Total Maximum Daily Load (TMDL) development or other management plans for restoration or protection.
Before each IWQR cycle is finalized and submitted to EPA, CTDEEP conducts an informational meeting and offers an opportunity for the public to review and comment on the report for at least 30 days after the report is public noticed.
The Final 2024 Connecticut Integrated Water Quality Report is now available. A public comment period was held from September 12, 2025 to October 14, 2025. A public meeting was held via zoom on September 17, 2025, from 11:00 a.m. - 12:30 p.m. (Eastern Time (US and Canada). Comments were submitted in writing and directed to Rebecca Jascot at DEEP.IWQR@ct.gov. Responses to Comments were reviewed and summarized by the Department. Thank you to all who participated. Visit the interactive online web mapping application to view the 2024 final assessment results.
Final 2024 IWQR Report
Final 2024 IWQR Factsheet
Appendix A-1. 2024 Connecticut 305b Assessment Results for Rivers and Streams
Appendix A-2. 2024 Connecticut 305b Assessment Results for Lakes
Appendix A-3. 2024 Connecticut 305b Assessment Results for Estuaries
Appendix A-4. Connecticut 305b Site Specific Fish Consumption Advisories
Appendix B-1. 2024 List of Impaired Waters for Connecticut (EPA Category 5 and 5R)
Appendix B-3. 2024 Pollution Control Measures for Waterbody Segments (EPA Category 4b)
Appendix B-4. 2024 Nonpolluting Impairments (EPA Category 4c)
Appendix D-1. 2024 State and Tribal Waters in Connecticut
Previous IWQR Documents
DEEP Water Quality Planning Information Listserv
The Connecticut Department of Energy and Environmental Protection uses the Department web site to provide information about topics pertaining to water quality based programs within Connecticut. If you would like to receive notice of water quality program updates by e-mail, please subscribe to the Water Quality Planning (WQP) Information listserv. Each time the web site is updated with materials relative to water quality based programs, you will receive an email notification with a link to the pertinent web page. To remove your name from the listserv, follow the unsubscribe steps outlined below.
How to Subscribe to the WQP Listserv
If you have an e-mail signature, header, and/or footer set up to be automatically included in emails, you will need to delete these before sending the subscribe request. Send an email to Listserv@List.CT.gov
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Content last updated December 19, 2025