Every two years, DEQ is required by the federal Clean Water Act to conduct a comprehensive analysis of Idaho's water bodies to determine whether they meet state water quality standards and support beneficial uses or if additional pollution controls are needed. This analysis is summarized in an "Integrated Water Quality Monitoring and Assessment Report" (Integrated Report), which is submitted to the U.S. Environmental Protection Agency (EPA) for approval. The report serves as a guide for developing and implementing water quality improvement plans (total maximum daily loads, or TMDLs) to protect water quality and achieve federal and state water quality standards. 

An Integrated Report must be approved by the EPA before it can be used by a state to guide its management decisions. Idaho's most recent approved version is its 2008 Integrated Report.  This document will continue to guide DEQ's water quality management decisions until the 2010 Integrated Report is approved by EPA.

The Integrated Report serves three functions. First, it is a reporting requirement of the Clean Water Act, so DEQ must prepare an Integrated Report to be in compliance with federal law. Second, it provides the public the opportunity to learn about and comment on the status of all of Idaho's waters.

Prior to 2002, the Integrated Report did not exist in its current form. Instead, two documents were prepared and submitted to the EPA. The first of these was a list (called a "§303(d) list") of all impaired waters in the state, as required under Section 303(d) of the Clean Water Act. The second was a report (called a "§305(b) report") that summarized the status of all of Idaho's waters, as required under Section 305(b) of the Clean Water Act. The Integrated Report is a combination of these two documents.

The Integrated Report classifies all of the state's waters into one of five different categories, which correspond to the five sections of the report.

> View the Final 2008 Integrated Report.

An individual assessment unit may be classified in more than one category. For instance, an assessment unit could be classified in Sections 1 or 2 OR Section 3. If the water is impaired or if water quality standards are not being met, it could be in Sections 4 and/or 5. For example, if a water body is listed as impaired due to temperature and flow alteration, it would be listed in Section 5 for temperature and in Section 4c for flow (flow is not considered a pollutant).

In addition to listing the water quality status of Idaho's water bodies, the Integrated Report also contains:

• A delineation of the assessment units based on the National Hydrography Dataset
• A description of the progress made toward assessing all Idaho surface waters
• A description of the basis for the status determinations
• A description of additional monitoring that may be needed to determine water quality standard attainment status, and, if necessary, to support development of TMDLs for each pollutant/assessment unit combination
• Schedules for additional planned monitoring
• Schedules for TMDL development reflecting the priority ranking of each pollutant/assessment unit combination

Section 1 contains only a few pristine waters that lie completely in wilderness or roadless areas and comply with all of Idaho's narrative water quality criteria. Idaho lists most waters that support their assessed beneficial uses and comply with all water quality standards in Section 2, below. This is because Idaho does not have a method to measure attainment of its wildlife and aesthetics beneficial uses. Even though Idaho's water quality standards state that compliance with general narrative standards is sufficient to show a water body is supporting the wildlife and aesthetics beneficial uses, DEQ conservatively lists most waters in Section 2. The only difference between waters listed in Sections 1 and 2 of Idaho's Integrated Report is the wilderness status of the waters in Section 1. (See DEQ's Water Quality Standards Web page for an explanation of water quality standards, criteria, and beneficial uses.)

Three types of water bodies fall into Section 4:

• Section 4a: Water bodies with approved TMDLs.
• Section 4b: Waters expected to meet standards; Idaho does not propose any 4b waters at this time.
• Section 4c: Water bodies impaired by pollution (e.g., flow alteration and habitat alteration) but not pollutants (click here to read about the difference between pollution and pollutants).

Water bodies listed in Section 5 include those from the 2002 Integrated Report that do not have an EPA-approved TMDL and those added since the 2002 Integrated Report because they were determined to be impaired using DEQ’s Water Body Assessment Guidance. Waters can only be removed from Section 5 by either having an EPA-approved TMDL or EPA approval to remove based on good cause.