Bartlett Dam and Reservoir Expansion Project

The need: Restoring lost capacity and increasing water supply

For decades, SRP has been partnering to manage a 13,000-square-mile watershed — an area of land where rain and melted snow drain into creeks and rivers. This water flows into the Salt and Verde rivers where dams operated by SRP form vital reservoirs. Like water, sediment is naturally transported through the Verde River and ultimately makes it to these reservoirs. Over time, this sediment builds up, reducing the overall amount of water that can be stored. These reservoirs, which you may know as lakes, store water for when the Valley needs it most.

Water storage along the Verde River

Northeast of Phoenix along the Verde River, SRP manages two dams and their corresponding reservoirs: Horseshoe and Bartlett. During wet winters, reservoirs are more likely to reach capacity, which requires SRP to release excess water that could have otherwise been stored for use during the dryer months and years.

The solution: Expanding Bartlett Dam

SRP is constantly evaluating ways to ensure that there is enough water to support our growing population while also planning for changing climate conditions. During a recent study along the Verde River, SRP’s engineers identified possible solutions that could protect the water supply and help increase total water storage. The most promising solution is to expand the size of Bartlett Dam to enlarge the reservoir’s capacity and update operating plans to better manage sediment buildup. The concept to modify Bartlett Dam and Reservoir came through an early planning study led by the Bureau of Reclamation. Section 40902 of the Infrastructure Investment and Jobs Act, P.L. 117-58 (Bipartisan Infrastructure Law [BIL]) granted authorization for the consideration of modifying Bartlett Dam and Reservoir under the Verde Reservoir Sediment Mitigation Project Federal Feasibility Study.

Project benefits

By expanding Bartlett Dam, the reservoir will be able to capture more water during wet winters. This means there will be more water available to use during drought periods, which are expected to last longer on average over time. Along with an expansion of Bartlett Dam, changes to reservoir operations will help SRP better manage sediment that flows into the reservoirs during large flood events. The water supplies made available by the project will help central Arizona manage shortage conditions on the Colorado River and help reduce our reliance on nonrenewable water supplies like groundwater.

While details are still being evaluated, the most effective solution would be to raise Bartlett Dam by about 100 feet. SRP completed a similar expansion project at Roosevelt Dam in the 1990s, which successfully increased reservoir capacity. At Bartlett, the additional capacity gained under the proposed plan would equate to a year’s worth of water for a million homes.

Supporting Colorado River shortages

SRP is committed to identifying ways to strategically manage regional water supplies for the benefit of all. In addition to protecting water for SRP customers, the Bartlett expansion will be essential to bringing new supplies of water to central Arizona that can help alleviate the current shortages on the Colorado River, another major source of water for the Valley.

Additional benefits

Aside from protecting the Valley’s water supply, this project will have a variety of other positive effects, which include:

• Potentially benefiting local wildlife by expanding riparian habitats, especially for bird species
• Increasing recreational opportunities that stimulate Arizona’s economy
• Improving SRP’s ability to balance safe flood operations and water storage

Next steps

SRP and 22 municipal, tribal and agricultural partners are working with the Bureau of Reclamation to complete a feasibility study that evaluates the proposal to expand Bartlett Dam. Following the study, a finalized plan will be presented to the U.S. Congress for consideration. Congress will then hold a vote to determine if the project should be approved.

Funding the project

The anticipated cost of this feasibility study is $28 million. Half of that cost will be covered by the federal government, with the other half split among SRP and the 22 funding partners. If construction is approved, the total project is estimated to cost around $1 billion. The construction costs will be shared among those benefiting from the project and will be determined through the completion of the feasibility study. The expansion project is expected to take 10–15 years to complete and will help secure more water in the Valley for generations to come.

FAQ

Want more information? Check out our in-depth water resiliency article or read the FAQ below to learn more about this project.