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Integrated Report Cycles – Clean Water Act Sections 303(d) and 305(b)

California’s Clean Water Act section 303(d) and 305(b) Integrated Report is developed in "cycles" with each cycle occurring every two years. Each Integrated Report cycle consists primarily of assessments from the three Regional Water Quality Control Boards that are identified "on-cycle" by the notice of solicitation The other six Regional Water Quality Control Boards that are "off-cycle" may also assess new high-priority data and make new listing or delisting decisions for one or more water segments.

Below is an overview of the process and approximate schedule used in developing the Integrated Report. The chart is not reflective of any particular "cycle" but generally depicts the amount of time that corresponds to each of the steps necessary to complete a single cycle.

Steps Approx. Months
1. Data Solicitation 6
2. Data Organization & Mapping 5
3. Data Analysis 13
4. Regional Board Public Process 10
5. State Board Public Process 10
6. USEPA Review & Approval 3

In Progress: 2020, 2018 | Current: 2014/16 | Previous


2020 Integrated Report - In Progress

The 2020 Integrated Report is currently in progress.  The Central Coast, Central Valley, and San Diego Regional Water Boards are “on-cycle” for 2020.  The other Regional Boards may choose to conduct “off-cycle” assessments.

2018 Integrated Report - In Progress

The 2018 Integrated Report is currently in progress.

2014/2016 Integrated Report - Current Integrated Report

This the current, active CWA Section 303(d) List and 305(b) Report

Previous Reports

2012 Integrated Report

2012 Integrated Report (CWA Section 303(d) List / 305(b) Report)
On July 30, 2015, the U.S. EPA issued its final decision regarding the waterbodies and pollutants added to California's 303(d) List. This replaces the 2010 California Clean Water Act section 303(d) List as California's current 303(d) List.

2010 Integrated Report

2010 Integrated Report (CWA Section 303(d) List / 305(b) Report)
On October 11, 2011, the U.S.EPA issued its final decision regarding the water bodies and pollutants added to California's 303(d) List. This replaces the 2006 California Clean Water Act 303(d) List as California's current 303(d) List.

Previous 303(d) Lists and 305(b) Reports
The 2010 Integrated Report is the first Integrated Report developed for the State of California. Previous assessments were developed by the State Water Board in separate documents and can be found at the following links:

Previous Clean Water Act Section 303(d) Lists


Previous Clean Water Act Section 305(b) Reports


Earlier 305(b) Reports are not available in digital format. These reports can be requested through the Public Records Center