Caring for the Snake River

The Snake River plays a vital role in providing electricity to Idaho Power’s 650,000-plus customers throughout southern Idaho and eastern Oregon. A healthy Snake River also benefits all other users — irrigators, land owners, wildlife and people who enjoy the river for boating, fishing and other recreational uses. 

Idaho Power is committed to enhancing the Snake River’s ability to provide clean water and clean power to our region for future generations. As part of that commitment, we have initiated programs to restore river channels, plant native vegetation, and reduce agricultural runoff to the Snake River.

These programs use a watershed-based approach to address the causes of elevated water temperatures, high algae levels, low dissolved oxygen, and mercury in fish. These programs are part of relicensing our hydroelectric projects in Hells Canyon. They are included in the Clean Water Act Section 401 Water Quality Certifications issued by the states of Idaho and Oregon. 

What are the Projects Idaho Power is Undertaking?

Restoring River Channels and Planting Native Vegetation 

Elevated water temperatures impact fish and wildlife habitat in the Snake River. Idaho Power’s Snake River Stewardship Program (SRSP) focuses on the causes of these higher temperatures by restoring sections of the river channel and planting native trees and shrubs along key tributaries. Projects in the Marsing/Homedale area include the expansion of island floodplains designed to reduce water surface area, increase water velocity, and increase channel depths. This reduces the surface area exposed to heating, decreases algae and aquatic plant growth, and improves habitat. New trees and shrubs along sections of tributaries shade these waterways, providing more diverse fish and wildlife habitat and reducing the amount of sediment and pollutants that enter the water. We have already planted sections of riparian vegetation along the Powder, Weiser, and Little Weiser rivers. 

 Reducing Agricultural Runoff 

We have three programs intended to reduce nutrient and sediment runoff from agricultural lands to the Snake River upstream of Brownlee Reservoir. The largest of these programs, the Snake River Methylmercury Management Program (SRMMP), focuses on conversion of flood and furrow irrigation to sprinklers or drip and is being piloted in 2025. 

The Grand View Program is similar to the SRMMP, focused on fields around Grand View, Idaho. 

Additionally, our partnership with the Riverside Irrigation District prevents thousands of pounds of phosphorus and sediment from entering the Snake and Boise rivers each year.  

Reducing phosphorus helps to limit algae and aquatic plant growth. This reduces the amount of plant material in the river where it uses precious oxygen as it decays. Idaho Power recently completed a 10-year study with the United States Geological Survey that showed this lack of oxygen is a key driver enabling the conversion of mercury to biologically toxic methylmercury in the Snake River watershed. This detailed science is the foundation of SRMMP development. Key points of the SRMMP include: 

  • Idaho Power has committed significant matching funds for agricultural producers and other partners such as the Natural Resources Conservation Service. This program is targeted at implementing sprinkler conversions and reducing agricultural run-off across the Malheur, Owyhee, Payette/Weiser, and Lower Boise sub-basins of the Mid-Snake.  
  • Idaho Power is coordinating with The Freshwater Trust and other partners to implement this program. 
  • Not all sprinkler conversion projects in Mid-Snake sub-basins are eligible for Idaho Power funding. Project funds will be used to support projects that result in the most cost-effective reduction in agricultural runoff.  
  • Each year, The Freshwater Trust will provide irrigation supply companies with a list of priority locations and projects to target. These suppliers will reach out to producers to assess interest and project feasibility before developing a preliminary project layout and budget. 
  • The first year of this program (2025) involves testing initial engagement with a limited number of irrigation suppliers. Following this initial phase, The Freshwater Trust will begin solicitating additional irrigation equipment supply partners to begin producer outreach and participation in the program. 

 For more information on the SRMMP, email projects@irrigationincentives.com or call 208-781-6318. 

For more information on the Grand View Program, contact Erick Peterson, Idaho Power Agricultural Representative, at EPeterson@Idahopower.com.