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Weak Infl ow Augurs Low Level for Lake Powell

Lake Powell’s storage is headed to its lowest level in nearly 10 years. T e Bureau of Reclamation (Reclamation) estimates the fi gure at a little more than 29 million acre-feet, or one-half of the lake’s storage capacity (see map). Meager precipitation in winter and spring contributed a below average in- fl ow into the lake, which is a storage fa- cility for the Colorado River Upper Basin states – Colorado, Utah, Wyoming and New Mexico. T ose states are required under the Colorado River Compact to provide a minimum annual fl ow of 7.5 million acre-feet to the Lower Basin states (Arizona, Nevada and California) for irrigation and municipal use. T at water is typically stored in and released from Lake Powell. Late-spring snowstorms in the Upper

Basin elevated water levels in the Green and the Upper Colorado rivers but the precipitation was not enough to have a signifi cant impact on Powell, partly because the dry soil was expected to absorb much of it, according to a June report by Katrina Grantz, hydraulic engi- neer with Reclamation’s Upper Colorado Region. T e report says the lake’s elevation

will hover around 3,599 feet through the summer before declining as runoff ebbs. T e infl ow of about 3 million acre-feet is about 42 percent of the average infl ow

for the 1981 to 2010 period. T e lake is expected to end the 2013 water year (which runs from Sept. 30, 2012 to Oct. 1, 2013) at 44 percent of capacity. “T e April-July most probable fore- cast did not change … and the overall water supply outlook remains signifi - cantly below average,” Grantz said. Since 2005, the Upper Basin has experienced “signifi cant year to year hydrologic variability,” according to Grantz. From 2005 through 2012, the unregulated infl ow to Lake Powell averaged 10.2 million acre-feet per water year. T e numbers have ranged from 4.91 million acre-feet in water year 2012 to a high of 15.97 million acre-feet in water year 2011. “T is has been an improvement over the persistent drought conditions of 2000 to 2004, which averaged a water year unregulated infl ow of 5.73 million acre-feet,” Grantz said. “However, based on observed infl ows and current fore- casts, water year 2013 unregulated infl ow is expected to be 4.77 million acre-feet, which would be a second below-average year in a row.” Grantz expects Lake Powell to

increase by only a few feet this spring and summer. Normal infl ow from spring runoff , in comparison, would cause lake levels to rise by about 40 feet (12 meters). • – Gary Pitzer

10 • Colorado River Project • River Report • Summer 2013

T e Sea’s renewable energy potential extends to the production of algae, which is converted into biofuel and other high-value prod- ucts. “From a biological and geo- graphic perspective Imperial Valley is probably one of the best places on the planet to grow algae; it’s hyper- productive,” said Stephen Mayfi eld, director of the San Diego Center for Algae Biotechnology at the Univer- sity of California, San Diego. Last year, the La Jolla-based company Synthetic Genomics pur- chased an 81-acre site in the Imperial Valley to test newly identifi ed and engineered algal strains. T is site has 42 open ponds, some as large as 240,000 gallons.

Cause for Hope? T ere was a time when ambitious recreational and environmental restoration plans were discussed for the Sea; such plans would have cost billions of dollars and never came to fruition. T at prospect has given way to the harsh reality that any future vision for the Sea has to be economi- cal and realistic. “I think the eff ort will initially be focused on pushing for the state to fulfi ll its Salton Sea restora- tion obligations outlined in the QSA enabling legislation, particu- larly knowing that air quality issues associated with a declining Sea may not necessarily be a current mitigation issue but have long-term consequences to our community and the QSA,” Shields said. “So while there is a distinction between mitigation and restoration right now, that is inevitably blurred in the future.” In an interview, Delfi no with

Defenders of Wildlife said “we are sort of stuck with the status quo and need to fi gure out how to move forward.” While a long term vision for the Sea has not arrived, the millions of dollars approved for the Salton Sea Authority feasibility study

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