Idaho's Comprehensive State Water Plan
The Idaho Water Resource Board is charged with the development of the Idaho Comprehensive State Water Plan. The plan includes the statewide water policy plan and associated component basin and water body plans which cover specific geographic areas of the state.
State Water Plan – Adopted November 28, 2012
As a component of the Comprehensive State Water Plan process, the IWRB can designate river segments with outstanding fish and wildlife, recreational, aesthetic, or geologic value as a State-Protected River. If the IWRB decides that the values of preserving an outstanding waterway in its existing condition outweigh the values of continued development, it can, subject to legislative approval, designate that waterway either a Natural River or Recreational River to protect existing resources and use. Over 2,745 miles of Idaho’s rivers are protected by the State. Designation may prohibit:
- construction or expansion of dams or impoundments,
- construction of hydropower projects,
- construction of water diversion works,
- dredge or placer mining,
- alterations of the stream bed, and/or
- mineral, sand, or gravel extraction within the stream bed.
Additional Information
- State-Protected River Segments list
- State-Protected River Segments map
- State-Protected River Segments details
Comprehensive Basin Plans
Comprehensive Basin Plans inventory and assess regional water resources in a specific river basin, waterway, aquifer, or geologic area. Listed below are the basins with comprehensive plans.
Click here to view a full-size interactive map outlining the basins with plans.
| Date | Basin Plan | Basin Map | Description |
|---|---|---|---|
| June 29, 1990 | South Fork Boise River Basin Plan | Basin Map | The South Fork Boise River is a major tributary of the Boise River, and its confluence with the Boise River is inundated by the Arrowrock Reservoir. The 1,310-square mile basin is mountainous with an extensive network of perennial streams. A major portion of the basin is covered by timber. The USDA Forest Service administers about 80% of the total land area. Timber harvest, recreation, and grazing are major activities in the basin. Two major storage reservoirs, Anderson Ranch and Little Camas, provide for irrigation, recreation, and flood control. |
| December 1992 | Henrys Fork Basin Plan | Basin Map | The Henrys Fork is a major tributary of the Snake River, draining about 3,200 square miles in Idaho and Wyoming. Land use is timber production and grazing in the uplands, with both irrigated and dry-land farming in the lower plains. The recreational resources in the upper basin are outstanding, with international recognition for quality fishing experiences. |
| December 1992 | Upper Boise River Basin Plan | The Upper Boise River basin lies above Lucky Peak dam and includes the North and Middle Forks of the Boise River and the Mores Creek drainage. The basin is about 1,375 square miles, and streams drain into the Lucky Peak Reservoir-Arrowrock Reservoir complex. Upstream of the reservoirs, the river and its tributaries contain excellent populations of wild rainbow trout and bull trout. Over 90% of the land is in public ownership, and a portion lies within the Sawtooth Wilderness Area. The Upper Boise River basin provides a variety of recreational settings and experiences. | |
| December 12, 1993 | Middle Snake River Basin Plan | Basin Map | The Snake River from Milner Dam to King Hill is delineated by the Snake River canyon with numerous springs which issue through the canyon walls. Water flow is dependent on releases from Milner Dam and return flows from the Snake River Plain aquifer. Agriculture is the dominant industry of the region, but the river serves other values as well. The river is home to a rich variety of fish and wildlife, and it provides recreational opportunities for residents. However, water quality degradation is a major concern that impacts all uses. |
| 1995 | Priest River Basin Plan | Basin Map | The Priest River basin lies in the Panhandle of Idaho, with small portions of the basin in Washington state and British Columbia, Canada. Upper Priest Lake and Priest Lake, the third largest natural lake in Idaho, are located in the upper half of the basin. Approximately 90% of the basin is publicly owned land, and numerous special management areas protect exemplary forest and wetland communities. The basin contains outstanding aesthetic quality, fish and wildlife habitat, and recreational opportunities. Timber and tourism are the two major industries in the basin. |
| January 12, 1996 | North Fork Clearwater River Basin Plan | Basin Map | The North Fork Clearwater River basin, from its headwaters in the Bitterroot Mountains to its western boundary at the confluence with the main Clearwater River below Orofino, encompasses approximately 2,500 square miles. Above Dworshak Reservoir, the basin is predominately public land managed by the US Forest Service, with the remainder of land mostly in private ownership. While timber is the predominant land use and industry in the basin, recreation is also a major use and a growing industry. |
| December 13, 1996 | South Fork Snake River Basin Plan | Basin Map | The South Fork Snake River originates in Yellowstone National Park and the basin encompasses all land draining into the river from the Idaho-Wyoming state line to the confluence with Henrys Fork. Water flow of the river is regulated by Palisades and Jackson Lake dams. Dry-land and irrigated agriculture is a predominant land use. The basin has many natural resource values: outstanding scenery, a quality fishery, and wildlife values provide diverse recreational opportunities. |
| February 5, 1999 | Payette River Basin Plan | Basin Map | The Payette River is a major tributary to the Snake River, draining about 3,320 square miles in west-central Idaho. Three major branches, the North, Middle, and South Forks, convey waters from the mountainous headwaters and converge to form the Payette River. Cascade Reservoir is the largest reservoir in the basin, and there are 25 additional water storage projects that provide for a variety of water uses. About 60% of the basin is publicly owned. Major industries are agriculture, timber, and recreation. Outstanding resources include bull trout focal habitat, bald eagle nesting, and the basin offers outstanding boating and fishing opportunities. |
| September 19, 2001 | Little Salmon River Basin Plan | Basin Map | The 576-square mile basin is located in northeastern Adams and southwestern Idaho Counties, and flows into the Salmon River at the northern side of Riggins (RM 86.7). The basin is mountainous and sparsely populated. Occupations in ranching, logging, and lumber manufacturing contribute to the basin’s economy. Tourism and related services are becoming more important locally, potentially helping to support the area during downturns typically experienced by natural resources-based economies. |
| January 13, 2005 | South Fork Clearwater River Basin Plan | Basin Map | The South Fork Clearwater River basin has two distinct parts. The northwestern portion, the Camas Prairie, is rolling plateaus and prairies, and a major dry land agricultural area of the State of Idaho. It accounts for about 20% of the basin’s land area. The eastern portion is forested, mountainous and sparsely populated with about 68% of the land area within the Nez Perce National Forest. The South Fork Clearwater River Plan was adopted by the Idaho Water Resource Board in 2004 and approved by the legislature in 2005. |
Comprehensive Aquifer Management Planning (CAMP)
Visit the Comprehensive Aquifer Management Planning webpage for information on and to view Comprehensive Aquifer Plans.
Minimum Stream Flow Water Rights
Idaho’s Minimum Stream Flow Program was approved by the Legislature in 1978 to preserve stream flows and lake elevations for public health, safety, and welfare. The minimum stream flow is the amount of flow necessary to preserve desired stream values, including fish and wildlife habitat, aquatic life, navigation and transportation, recreation, water quality, and aesthetic beauty.
To learn more, visit the Minimum Stream Flow Water Rights webpage.
Archived State Water Plans & Other Records
Archived State Water Plans
Proposed Addition of a Sustainability Section to the State Water Plan
At the request of Governor Otter, IWRB has developed a proposed change to the Idaho State Water Plan through the addition of a new Sustainability section. The proposed Sustainability section is the result of a robust public involvement process.
- Proposed Sustainability Section to the SWP – May 2016
- Boise Agenda, Audio – June 7, 2016
- Hailey Agenda, Audio – June 13, 2016
- Twin Falls Agenda, Audio – June 28, 2016
- Sandpoint Agenda, Audio – July 20, 2016
- Lewiston Agenda, Audio – August 23, 2016
- Idaho Falls Agenda, Audio – August 30, 2016
- Chubbuck Agenda, Audio -September 14, 2016
- Written Comments and Exhibits on Proposed Sustainability Policy – 2016
- Summary of Public Comments regarding Proposed Sustainability Policy – 2016
- Final Sustainability Section – Adopted November 2, 2016
2012 Revision Process
On November 28, 2012, IWRB adopted a revised Idaho State Water Plan. The revised plan is the result of extensive public involvement and reflects the changing landscape of water in Idaho. The 2012 plan updates many policies from previous plans and adds policies related to new water management issues.
- State Water Plan – Adopted November 28, 2012
During the public comment period from June 18, 2012 through September 21, 2012, seven public hearings were held and written comments and exhibits were submitted. After considering the comments and testimony, the assigned board committee made recommendations that are reflected in the current plan.
Testimony Recordings
2025 Proposed Changes to the State Water Plan and Eastern Snake Plain Aquifer Comprehensive Management Plan
The 2025 Idaho Legislature passed Senate Concurrent Resolution 110 directing the Idaho Water Resource Board to revise State Water Plan policies 4B, 4D, and 4E and the ESPA Comprehensive Aquifer Management Plan to establish a state-funded ESPA managed recharge goal of 350,000 acre-feet on an average annual basis.
- Proposed Changes to SWP and ESPA CAMP – July 2025
Upcoming Meetings & Public Hearings
Public Hearings