Storms Prompt SRP Water Releases

Salt River will Likely be Flowing through Valley Starting this Weekend

PHOENIX – The third and largest in a series of significant winter storms has prompted Salt River Project to release excess water today from its two reservoirs on the Verde River to create additional storage capacity. The releases are the third in as many years, meaning the normally dry Salt River will be flowing through the Valley by Friday and through this weekend.

With the two storage reservoirs on the Verde River expected to soon fill to capacity — and a forecast of unprecedented precipitation this week on the Salt and Verde watersheds — SRP initiated releases from Bartlett Dam this morning. The initial release was 2,000 cubic feet per second (cfs), which will likely increase over the next few days to 50,000 to 70,000 cfs. That water is expected to reach Granite Reef Dam, located east of Mesa, tonight, with peak flows through the Valley in the Salt River expected to intensity over the weekend.

The releases will have some impact on local residents once the water reaches the Valley. After the water is spilled from Granite Reef Diversion Dam and moves west down the Salt River, the river crossing at McKellips Road will likely be closed by Friday or Saturday — and likely throughout the spring.

SRP’s reservoir system is currently at 73 percent of capacity, compared to 91 percent a year ago. The Verde River system is 35 percent full (Horseshoe Lake, 28 percent; Bartlett Lake, 39 percent). The much-larger Salt River reservoir system is at 79 percent, with Roosevelt Lake – which holds about two-thirds of SRP’s water capacity — at 76 percent full.

Charlie Ester, SRP’s manager of Water Resource Operations, said the current storm — and the likelihood of a continued El Nino-influenced wet winter — will mean all of SRP’s six reservoirs on the Salt and Verde rivers will fill this winter, with water releases likely continuing through the Valley into the late spring.

Significant runoff in December 2008 and the winter of 2009 prompted the release of water at Roosevelt Lake after the lake’s elevation rose to its highest-ever elevation and forced federal storage restrictions. A Roosevelt Lake elevation greater than 2,151 feet – which is considered full – is designated as Flood Control Space, as regulated by the Army Corps of Engineers’ Water Control Manual. The Corps’ Water Control Manual specifies release rates during the rising and falling stages of storage at Roosevelt Lake and a 20-day drawdown period to meet environmental requirements.

Published on behalf of Salt River Project
SRP is the largest supplier of raw water in the greater Phoenix metropolitan area, normally delivering more than 1 million acre-feet annually. For more information, visit srpnet.com.

Technorati Tags: Salt River Project, SRP