Idaho Water Quality Standards
Regional Water Quality Standards Information
WQS Home
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Recent Actions and Request for Comments in Idaho
Idaho Water Quality Standards
Idaho WQS Effective for Clean Water Act Purposes
Guidance for Pacific Northwest State and Tribal Temperature Water Quality Standards
Idaho Waterbody and Designated Use Data
Enviromapper for Idaho
Contacts
| Idaho Department of Environmental Quality |  | U.S. Environmental Protection Agency, Region 10 |
1410 North Hilton
Boise, ID 83706
Fax (208) 373-0576
Don Essig, dessig@deq.state.id.us,
(208) 373-0119 | | 1200 Sixth Ave, Suite 900
Seattle, WA 98101
Fax (206) 553-0165
Lisa Macchio, macchio.lisa@epa.gov
(206) 553-1834 |
Recent Actions and Request for Comments in Idaho
Public Comment Period Extended to Dec. 5 on Draft Idaho Mixing Zone Guidance
Idaho DEQ has developed a draft Mixing Zone Technical Procedures Manual to guide Idaho DEQ staff, federal water quality permit writers, and regulated entities on:
• conducting a biological, chemical, and physical appraisal of the receiving water;
• accounting for data limitations;
• determining the appropriate mixing zone model; and
• selecting model input parameters.
Idaho DEQ invites public comment on the draft guidance through December 5, 2008
Draft mixing zone guidance: Mixing Zone Technical Procedures Manual (PDF) (117pp, 1MB)
EPA Withdraws Federally Promulgated Uses in Idaho
On November 5, 2008, EPA withdrew federally promulgated designated uses for four waterbodies in Idaho: a section of the South Fork Coeur d'Alene River, a section of Canyon Creek, the Blackfoot River and Soda Creek. EPA withdrew its federally promulgated use designations of cold water biota for each of these waterbodies because Idaho DEQ adopted these uses, where previously the State's water quality standards did not have an aquatic life use for these waters. The Clean Water Act requires states and tribes to designate "fishable/swimmable" designated uses for their waters or perform and submit a use attainability analysis to EPA for approval, if they can demonstrate that the use is not attainable.
Federal Register notice
What are Water Quality Standards (WQS)?
Water quality standards are the foundation of the water quality-based control program mandated by the Clean Water Act. Water Quality Standards define the goals for a waterbody by designating its uses, setting criteria to protect those uses, and establishing provisions to protect water quality from pollutants.
A water quality standard consists of four basic elements:
- designated uses of the water body (e.g., recreation, water supply, aquatic life, agriculture),
- water quality criteria to protect designated uses (numeric pollutant concentrations and narrative requirements),
- an antidegradation policy to maintain and protect existing uses and high quality waters, and
- general policies addressing implementation issues (e.g., low flows, variances, mixing zones).