DEQ is required to review its water quality standards at least once every three years.  This process, called triennial review, is required by Section 303(c) of the Clean Water Act and must include the opportunity for public and EPA review of the standards as well as DEQ internal review.  The review is intended to ensure that standards meet public concerns, reflect new scientific and technical information, and follow EPA guidelines.   

Certain parts of Idaho's water quality standards are required under the Clean Water Act (uses, criteria, and antidegradation).  Other parts are specifically identified in the Clean Water Act, but are optional.  Idaho's water quality standards address the "optional" topics of mixing zones, variances, and low flows.  Idaho's water quality standards also contain other elements, such as definitions, application of water quality criteria, and wastewater treatment requirements.  Federal regulations only require triennial review for those elements that are required and optional under the Clean Water Act.  However, DEQ will consider all topics contained in its water quality standards in the 2005-2008 triennial review. 

Although DEQ typically conducts ongoing reviews/revisions of standards on an as-needed basis, it has also completed four triennial reviews (1993, 1995, 1997, 2002). More on the history of Idaho's triennial reviews.

 In 2005, DEQ is initiating a more formalized triennial review process that emphasizes public involvement in three phases:

The process will gain more focus as topics are selected and as changes to water quality standards are proposed; this effort will result in a comprehensive and holistic review of water quality standards.

 Phase 2:  Research Followed by Negotiated Rulemaking

For each priority topic from Phase 1, DEQ will research available information and science, consider different options, and evaluate how implementation of new approaches may impact water quality, water users, and regulated industries.  DEQ will review each topic separately, and will use a variety of vehicles to conduct a thorough review, including in-house staff review, independent contractor reports, and technical workgroups. As DEQ's review of each topic nears completion, DEQ will develop a fact sheet describing that topic in greater detail; these fact sheets will be available on DEQ's Web site.  This will assist DEQ and the public in preparing for the rulemaking negotiations.

At DEQ, the negotiated rulemaking process is initiated with a notice and an invitation for all interested parties to participate.  DEQ will develop proposed revisions to regulations and guidance as appropriate and will provide notice for a series of public workshops to collaborate with the public on proposed changes.  DEQ may hold one or more public hearings when revising water quality standards. 

 Phase 3:  Final Public Comment and Amendment and Adoption of New and

 Revised Standards

DEQ will hold public comment periods on the new and revised standards and will respond to comments in order to prepare a final draft of each regulation.  Once a final draft has been prepared, it must be approved by the Idaho Board of Environmental Quality and reviewed and not rejected by the Idaho Legislature.  At this point, the new standards become part of Idaho's Administrative Rules.  The new rules will then be submitted to EPA Region 10 for review and approval.

This information summarizes Idaho's water quality standards and is not intended to be all-inclusive. Detailed requirements are outlined in DEQ's Water Quality Standards and Wastewater Treatment Requirements.

Note: Some PDF files do not open properly due to computer setting conflicts. If you have difficulty opening these or any PDF files, try changing the default settings in Adobe Acrobat Reader.  See DEQ's About PDF Files (specifically Problem 1, suggestions D, E, and F) for guidance.