New Reservoir Will Funnel Colorado River Water to Nevada
A bill that directs the Bureau of Reclamation to construct a new reservoir to capture billions of gallons of Colorado River water requested by Arizona and California users but not used, was signed into law today by President George W. Bush.
Included in the massive HR 6111 Tax Relief and Health Care Act, the measure will enable the capture and use of billions of gallons of water that would otherwise flow down the Colorado River into Mexico.
The $84 million reservoir project to be built in Southern California would be funded by the state of Nevada in exchange for the right to withdraw a total amount of 280,000 acre-feet of water on an as-needed basis.
“We in Southern Nevada owe a great debt of gratitude to Senators [Harry] Reid and [John] Ensign for championing this bill, which provides yet another tool to help us protect the reliability of this community’s water supply,” said Southern Nevada Water Authority General Manager Patricia Mulroy.
“Like the Arizona and California water storage banks we have created, this new reservoir allows us to optimize our use of the Colorado River,” said Mulroy.
Under the rules governing use of the Colorado River, irrigators or municipalities can request that the Bureau release water from Lake Mead for their use.
But it often takes three days for that water released from Parker Dam to reach its destination at Imperial Dam. If during that period the requestor no longer needs the water due to rainfall or other circumstances, they have the option of “canceling” the order.
There is currently no way to capture and store that water for later use, and it is not counted against the requestor’s allotment.
Any water exceeding user demand that arrives at Imperial Dam and cannot be sent to another user, sent to storage, or delivered as part of scheduled deliveries to Mexico is inadvertently delivered to Mexico in excess of Treaty obligations and is considered to be non-storable water.
Non-storable water may also result from infrequent and unregulated inflow from numerous desert washes and the Gila River that discharge into the Colorado River.
The proposed reservoir would be located within Imperial County, about 30 miles east of the city of El Centro, California, and 25 miles west of the city of Yuma, Arizona.
The proposed reservoir site is north of the All-American Canal at the former Brock Ranch Research Center, an experimental farm area extensively disturbed by past agricultural operations.
The site lies fully within Reclamation withdrawn lands – federal lands withdrawn from some or all of the public land laws, including the mineral laws, which transfers jurisdiction for Reclamation project purposes.
The project includes three primary physical components, the reservoir, an inlet canal, and an outlet canal.
The Bureau estimates that the proposed reservoir, known as the “Drop 2 Structure” will conserve an average of 60,000 acre-feet of water–nearly 20 billion gallons–per year.
Over the structure’s projected 50 year lifespan, the total savings equates to three million acre-feet.
A draft environmental assessment prepared for the Bureau of Reclamation Yuma Area Office by Science Applications International Corp. of Santa Barbara, California was issued in November. It shows that the project will create no significant environmental impact if mitigation measures promised by the Bureau of Reclamation are followed.
The environmental assessment states that construction activities will follow biological mitigation measures. Revegetating or other means of erosion control will be implemented following construction. Tree removal will be restricted to periods outside the breeding season for most raptors and songbirds, and compliance with all relevant requirements of the federal Endangered Species Act is expected.
The Bureau of Reclamation will consult with the U.S. Fish and Wildlife Service to identify appropriate mitigation measures for protection and maintenance of habitat at Gasden Bend for a federally listed endangered bird, the southwestern willow flycatcher. Mitigation measures could include preservation of habitat offsite, and preservation of moist soil conditions within habitat. Mitigation measures would render this cumulative impact “insignificant,” according to the environmental assessment.
A section of the inlet canal crosses the nearby Flat-Tailed Horned Lizard Management Area, a concern raised in public scoping meetings on the reservoir project. The environmental assessment states that the Bureau of Reclamation shall compensate for impacts to flat-tailed horned lizard habitat consistent with the reptile’s Rangewide Management Strategy.
The reservoir project could take place at the same time as the planned lining of 35 miles of the Coachella Canal and 23 miles of the All-American Canal with concrete to save water that has been seeping into the ground since the canals were built. The lining projects are expected to save 77,000 acre-feet of Colorado River water.
But the environmental assessment acknowledges that the combined construction projects could be noisy, raise dust, and spill fuels, lubricants, and hydraulic fluids.
Both projects would temporarily degrade recreational experience in the project area, through construction dust and noise, trail detours and potential impacts to the canal fishery.
Sedimentation downstream is a potential hazard, the assessment states, but because grading, construction, and desilting operations would be completed under a stormwater general permit, erosion-related best management practices would be used.
“Not only is this good for Nevada and the entire river basin, it is just good common-sense water management policy,” Mulroy said. “Like the lining of the All-American Canal, we view the construction of the Drop 2 structure as an important water efficiency measure. Those of use who rely upon the Colorado River cannot afford to waste a drop.”
The Bureau of Reclamation has not yet established a construction schedule for the reservoir project.
Southern Nevada Water Authority spokesman Scott Huntley said, “We treat this as a conservation measure. This water is not intended for regular use, it’s essentially a drought reservoir.”
Huntley said, “We are now using less water in the valley in raw terms than we were five years ago even though we’ve added average of 60,000 residences per year.”
“But we anticipate that exercising our in-state water rights, probably within a decade or so we will need to bring on new sources of water to cover new construction, at present growth rate,” he said.
Huntley says that 70 percent of all the water used in Las Vegas is used to water landscapes such as golf courses and lawns. The Southern Nevada Water Authority has just started a new program to pay people $2 per square foot to remove grass from their yards and replace it with landscaping that does not require watering.
According to recently passed municipal laws in the Las Vegas Valley, new homes are not permitted to plant grass in front yards, and they are now limited to a maximum of half grass in the back yards.