Water Quality Assessment

The Integrated Report (IR) contains information on the quality of Wyoming’s waters, including those waters that have been identified as not meeting water quality standards.

Section 305(b)
The CWA requires each state to submit a report to EPA every two years describing the status of its surface and ground waters. This document is commonly referred to as the “305(b) Report”, which includes an assessment of existing water quality in Wyoming, and an overview of past and proposed water pollution abatement efforts.

Section 303(d)
Section 303(d) of the CWA, and Title 40 part 130 of the Code of Federal Regulations (40 CFR part 130) requires each state to develop a list of waters that are not attaining water quality standards and are not expected to meet state water quality standards even after application of technology-based controls for point sources or other control requirements, such as best management practices (BMPs) for nonpoint sources of pollution. The 303(d) list is a subset of all of the impaired waters listed in the comprehensive 305(b) water quality report.  Section 303(d) also requires that states develop total maximum daily loads (TMDL) for all waters on the 303(d) list. Waters on the 303(d) list must be prioritized for TMDL development based on the severity of each listing. Each state must submit a 303(d) list of impaired and threatened waters to EPA by April 1st of each even numbered year. EPA must review and approve or disapprove the 303(d) list within 30 days of submittal.

Wyoming’s Integrated 305(b) and 303(d) Report combines the requirements of both reports into a single document.  The current and previous versions of Wyoming’s Integrated 305(b) and 303(d) Report are available in the reports section of this site.