TMDL - The Integrated Report
303(d) List of Water Quality Limited Segments and 305(b) Surface Water Quality Assessment
Section 303(d) of the Clean Water Act requires the identification of water bodies that do not meet, or are not expected to meet, water quality standards (i.e., impaired water bodies). The affected water body, and associated pollutant or stressor, is then prioritized in the 303(d) List. The Clean Water Act further requires the development of a Total Maximum Daily Load (TMDL) for each listing. In 2008, California began integrating the 303(d) List of Impaired Waters and the 305(b) Water Quality Assessment Report into a single report (Integrated Report). This Integrated Report will satisfy the requirements of both CWA Sections 303(d) and 305(b).
What's New!
2026 Integrated Report - IN PROGRESS
The Central Valley Water Board will assess all readily available data for waters in the San Joaquin River watershed. Readily available data for the Sacramento River watershed, the Sacramento - San Joaquin River Delta, and the Tulare Lake Basin will be considered during future Integrated Report cycles. The data solicitation notice for the 2026 Integrated Report cycle can be viewed on the State Water Board website:
2024 Integrated Report - IN PROGRESS
The Central Valley Water Board will assess all readily available data for waters in the Sacramento River watershed. Readily available data for the San Joaquin River watershed, the Sacramento - San Joaquin River Delta, and the Tulare Lake Basin will be considered during future Integrated Report cycles. On February 3, 2023, the State Water Board issued a Notice of Opportunity for Public Comment and Public Hearing for the Draft 2024 California Clean Water Act Section 303(d) List & Board Hearing. A State Water Board hearing will be held on March 21, 2023 and the public comment period closes on April 3, 2023. More information on the 2024 Integrated Report for California, including the Notice, the draft 303(d) list, and the draft Staff Report can be found at:
2020-2022 Integrated Report - The Current 303(d) List
The Central Valley Water Board assessed all readily available data for waters in the Central Valley Region.The 2020-2022 Integrated Report was adopted by the State Water Board on January 19, 2022 and approved by U.S. EPA on May 11, 2022.
Integrated Report Listing Policy
The Water Quality Control Policy for Developing California’s Clean Water Act Section 303(d) List describes the process by which the State Water Resources Control Board and Regional Water Quality Control Boards will comply with the listing requirements of section 303(d) of the federal Clean Water Act.
Email Subscription List
Subscribe to the Impaired Waterways 303(d) List email list to receive notifications and updates.
Contact Us
- Program Contact
Jay Simi
(916) 464-4833
Jay.Simi@waterboards.ca.gov
- Web page problems: webmaster5@waterboards.ca.gov
