Water releases from Verde River create storage capacity and protect Dam as runoff increases

For the first time since 2019, the Salt River Project (SRP) has begun low-level water releases from Bartlett Dam on the Verde River, which are expected to continue through March. These types of water releases are necessary in years with lots of snow. They create additional storage capacity behind the Dam for the anticipated high spring runoff from all the winter snowmelt. This protects the Dam and ensures public safety.

The process includes releasing water into the normally dry Salt River from the canal system or directly into the Salt River at Granite Reef Dam. SRP then provides this water to the cities and irrigation districts that take deliveries from its system so it can be put to beneficial use. The water SRP releases will also flow downstream in the Salt River and recharge the aquifer, which helps Valley water providers. While the releases are expected to be maintained at a low level, the water will eventually be visible flowing through the normally dry Salt River, resulting in the closure of McKellips Road in the East Valley. 

The Salt and Verde reservoir systems are now nearly in balance, which means the annual demand is close to the annual supply. According to measurements taken recently by a team of SRP hydrologists, they have determined that snowpack on the 13,000-square-mile watershed that replenishes the six Salt River and Verde River reservoirs is the deepest it’s been in nearly two decades and the second deepest in 30 years.

As the climate continues to change, research shows the Verde River watershed will experience dryer dry periods and wetter wet periods, which means maintaining SRP’s reservoir storage capacity is critical to managing variations in weather and river flows. To find a long-term solution, SRP is working on increasing the storage capacity for the Verde River reservoir system over the next decade. A group of 23 partners, including the AMWUA cities, other municipalities, tribal, and agricultural, have committed to support the U.S. Bureau of Reclamation’s feasibility study of options to modify Bartlett Dam , which would improve the management of water resources provided by the Verde River, including reducing the need for such water releases.

SRP is also working with the Bureau of Reclamation and the U.S. Army Corps of Engineers to improve its operational flexibility in Lake Roosevelt’s flood control space. Roosevelt Dam contains around 62 feet of additional storage capacity above the conservation pool behind the Dam. SRP must release water within the Flood Control Space within 20 days. SRP is partnering with federal agencies to evaluate options to extend the release period, so there is more time to deliver the water to beneficial use or to store it underground for later use.

An additional project - the SRP CAP Interconnection Facility - currently in the design phase, will allow excess SRP water to be transported via the CAP canal and enable cities and irrigation districts connected to the CAP system to more easily put spill water to use. Currently, CAP water can move through SRP’s system, but SRP water cannot move through the CAP system.

As noted last week - this wet winter is positively impacting the Salt and Verde systems by raising the levels of Lake Roosevelt and its other reservoirs, which is good for Valley communities. In contrast, the Colorado River system’s yearly demand has exceeded annual runoff due to a historic drought, warmer and drier hydrologic conditions in the Colorado River basin, and being over-allocated. With above-average snowfall in the Rockies, the Colorado River will continue to produce much less water than it did in the previous century. This means that the AMWUA cities and all of Arizona must reduce reliance on this supply. The AMWUA cities have built diverse water portfolios with more than one water source . While the Salt and Verde reservoir systems experience favorable conditions, we still need to use all of our water supplies wisely so we can continue to thrive here in the desert.

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To learn more about our surface water supplies, visit Water Use It Wisely's latest blog - Tale of Two Watersheds .

For over 50 years, Arizona Municipal Water Users Association has worked to protect our member cities’ ability to provide assured, safe, and sustainable water supplies to their communities. For more water information, visit www.amwua.org .