Protecting Public Health and the Environment.

Integrated Report

The federal Clean Water Act requires states to conduct a bi-annual comprehensive analysis of state waters to determine if water bodies meet state water quality standards and thus support beneficial uses, or if additional pollution controls are needed. DEQ meets this requirement by preparing Idaho's Integrated Report.

After a public comment period, DEQ submits the Integrated Report to the U.S. Environmental Protection Agency (EPA) for approval and makes it available to the public. The report serves as a guide for developing and implementing water quality improvement plans (total maximum daily loads) to protect water quality and achieve federal and state water quality standards. An Integrated Report must be approved by EPA before it can be used by a state to guide its management decisions. 

Idaho's most recent approved version is its 2014 Integrated Report. The 2014 report was submitted to EPA for review on February 15, 2017, and approved by EPA on June 5, 2017 (EPA Approval Letter).

There are several ways to access information in Idaho’s 2014 Integrated Report:

  • Read the background and summary information provided below.
  • Download the report document, which includes background, methods, and state-wide summary information. The report also includes appendices that describe the status of all water bodies in the state.
  • View a pdf map of all water bodies in the state (32 x 42 inches)
  • Use an interactive map to search for water body-specific results
  • Download the Integrated Report GIS layer and associated metadata

Purposes of the Integrated Report

The Integrated Report serves the following three functions:

  • It satisfies the requirements of Clean Water Act sections 305(b), 303(d), and 314 by listing the current conditions of all state waters (required by §305(b)), including publicly owned lakes (required by §314), and lists waters that are impaired and need a total maximum daily load (TMDL) (required by §303(d)).
  • It informs the public about the status of state waters, enabling interested parties to comment on the status of all Idaho’s waters and provide relevant data.
  • It provides a unique opportunity for the public to understand the overall status of Idaho’s water quality and gain a better understanding of how DEQ is maintaining, improving, and protecting Idaho’s waters.

Organization of the Integrated Report

The Integrated Report presents background information about the waters of Idaho, DEQ’s water pollution control program, and special concerns affecting water quality. It also presents surface water monitoring and assessment summaries, including a discussion about public health issues. The report also provides an overview of Idaho’s ground water monitoring and assessment and a summary of public participation in developing the Integrated Report.

The report’s appendices include schedules for TMDL development that reflect the priority ranking of waters needing a TMDL, maps showing the status of all Idaho waters, DEQ’s response to public comments, and any other relevant supporting information for the Integrated Report. The appendices also contain lists showing the classification of all state waters into at least one of five different categories, anda list of assessment unit-cause combinations that EPA approved to be delisted (removed) from Categories 4 or 5.

Category 1: Waters of the State Wholly within Designated Wilderness or Inventoried Roadless Area Where Standards are Presumed to be Attained

Category 1 waters are those wholly within a designated wilderness or inventoried roadless area where water quality standards are presumed to be attained for all beneficial uses.

Category 2: Waters of the State Attaining Some Standards

Category 2 waters fully support those beneficial uses that have been assessed. Some beneficial uses have not been assessed due to insufficient data (or no data) and information.

Category 3: Waters of the State with Insufficient Data and Information to Determine if Any Standards are Attained

Category 3 waters have insufficient data or information to determine if water quality standards are attained and if beneficial uses are supported. Category 3 is meant to be temporary until sufficient data and information are obtained to support a designated use attainment determination. However, in Idaho a water may remain in Category 3 under any of the following circumstances: (1) the stream has no flow when visited by DEQ (i.e., is intermittent); (2) access to the monitoring site was denied; or (3) the monitoring site is inaccessible. When DEQ encounters any of these circumstances, every attempt will be made in subsequent years to collect sufficient data and information to support a designated use attainment determination for these waters.

Category 4: Waters of the State Impaired for One or More Beneficial Uses but Not Requiring the Development of a Total Maximum Daily Load

Category 4 water bodies are grouped into one of three subcategories:

  • Category 4a: TMDL completed and approved by EPA.
  • Category 4b: Waters that have pollution control requirements in place, other than a TMDL, and are expected to meet standards within a reasonable period of time.
  • Category 4c: Water bodies impaired by pollution (e.g., flow alteration and habitat alteration) but not pollutants. According to EPA, water bodies impaired by pollution do not require development of a TMDL.

Category 5: Waters of the State for Which a TMDL is Needed

Impaired water bodies that do not meet applicable water quality standards for one or more beneficial uses by one or more pollutants are placed in Category 5. Category 5 is a streamlined §303(d) list that excludes waters that have an EPA-approved TMDL (Category 4a), waters addressed by other pollution control measures (Category 4b), and waters impaired by pollution (Category 4c), such as flow alteration or habitat modification. Waters can only be removed from Category 5 by having either an EPA-approved TMDL or EPA approval to remove based on good cause.

In some cases, a water body may be classified in more than one category. If the water is impaired or if water quality standards are not being met, an assessment unit may show up in both Category 4 and 5 of the Integrated Report. Most occurrences of such multiple listings are for water bodies that are impaired for multiple pollutants or pollution (e.g., flow or habitat alteration). For example, if a water body is impaired by a pollutant (e.g., temperature) and pollution (e.g., flow alteration), then the water body would be listed in Category 5 for temperature and Category 4c for flow alteration.

2014 Integrated Report

The 2014 Integrated Report presents information about the status of Idaho’s waters based on DEQ data and other readily available data or information from the past five years (2010–2014). The report presents background information about the waters of Idaho, DEQ’s water pollution control program, and special concerns affecting water quality. Also presented are surface water monitoring and assessment summaries, including a discussion about public health issues. The report also provides an overview of Idaho’s ground water monitoring and assessment efforts and a summary of public participation in developing the Integrated Report.

Highlights of the 2014 Integrated Report

  • Based on existing and readily available water quality data and information assessed for the 2014 Integrated Report, 33% of stream/river miles and 6% of lake acres are fully supporting state water quality standards, 36% of streams and 55% of lakes are not fully supporting water quality standards, and 31% of streams and 39% of lakes have not been assessed (see summary table below).
  • Compared to the 2012 Integrated Report, the percent of stream/river miles fully supporting beneficial uses has increased from 30% to 33%, and the percent of lake acreage fully supporting beneficial uses has remained the same at 6%.
  • DEQ delisted 307 AU-cause combinations from Categories 4 and 5 during the 2014 Integrated Report cycle.
  • During the 2014 Integrated Report cycle, DEQ assessed support of beneficial uses within waters using procedures outlined in Water Body Assessment Guidance (WBAG), 2nd Edition (Grafe et al. 2002). In October 2016 DEQ finalized WBAG 3rd edition, which will be used to assess beneficial use support status of waters during the 2016 Integrated Report cycle.
  • Appendix A of the report highlights several nonpoint source program success stories. In Bear Valley Creek in west-central Idaho, restoration efforts and modification of land management that have resulted in sediment reductions and water quality improvements. In addition, three water bodies are highlighted as making progress in achieving water quality standards: the lower South Fork Payette River, located in west-central Idaho, Rapid Creek in southeastern Idaho, and Shoshone Creek in southern Idaho.
  • The report includes a description of Idaho’s antidegradation implementation procedures (IDAPA First adopted by Idaho and approved by EPA in 2011, final changes regarding insignificant degradation became effective in 2014.
  • Idaho’s policy on tribal waters has been clarified, including a description of how the policy is planned to be implemented during the 2018 Integrated Report, once EPA’s ATTAINS database is finalized.
  • The report describes how DEQ prioritizes development of Total Maximum Daily Loads (TMDL) for impaired waters.
  • The report includes an updated discussion of nutrients, including harmful algal blooms.
  • The report describes how DEQ consults with Basin Advisory Groups (BAGs) and Watershed Advisory Groups (WAGs) pursuant to Idaho House Bill 271, which was signed into law on April 11, 2013, and clarifies DEQ decisions that are subject to BAG and WAG consultation.

Summary of Water Quality Support Status in the 2014 Integrated Report


  Number of
Assessment Units
Miles of
Number of
Assessment Units
Lake Acres
Fully Supporting        
      Category 1 373 4,776 209 5,646
      Category 2 1,397 26,807 39 21,824
Not Assessed        
      Category 3 1,441 29,888 318 182,964
Not Supporting        
     Category 4a 2,466a 25,685 69a 206,884
     Category 4b 4a 51 0a 0
     Category 4c 558a 7,376 12a 85,785
     Category 5 792a 10,799 34a 205,175

aAU-cause combinations

NOTE: Because assessment units can fall in more than one category, category numbers cannot be summed to get support status or statewide totals.

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Staff Contacts

Federal Reporting Coordinator
Amy Steimke
DEQ State Office
Water Quality Division
1410 N. Hilton
Boise, ID 83706
(208) 373-0153

Previous Integrated §303(d)/§305(b) Reports

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