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Monitoring, Assessment and TMDLs: Arizona

Arizona Department of Environmental Quality (ADEQ) is responsible for conducting monitoring, assessment, reporting under CWA Sections 303(d) and 305(b) and TMDL development for the State of Arizona. More information about Arizona's programs may be found at ADEQ's Water Quality Monitoring and AssessmentExitpage.

On this page:

Water Quality Standards

Information on Arizona’s Surface Water Quality Standards can be found at:

Arizona's Integrated Report

On September 14, 2018, EPA determined that Arizona's 2018 303(d) List partially met the requirements of Clean Water Act Section 303(d), and approved each of the State's listings included in its 2018 303(d) List. The approval letter and enclosure are provided below under EPA Documents. The State’s 303(d) list is available from the website linked under State Documents.

EPA Documents

State Documents

Arizona’s 2018 Clean Water Act Section 303(d) list of waters requiring a TMDL is available at the Arizona Department of Environmental Quality (ADEQ) website.Exit

TMDLs in Arizona

Information on the status of TMDLs being developed or previously developed by ADEQ can be found at: