...drought that has impacted our hydroelectric power generation,” says LaVerne Kyriss, spokeswoman for Western Area Power Administration, a Dept. of Energy agency that markets and delivers power in 15 states.

PRESSURE DROP Low water behind Glen Canyon Dam reduces powerhouse turbine efficiency. (Photo courtesy of Southern Nevada Water Authority)

A five-year drought has drained Lake Powell in Arizona to 43% of capacity, reducing the hydraulic head entering Glen Canyon Dam’s turbines by 30%. Further up the Colorado River, Lake Mead is at 55% capacity, reducing peak hydroelectric generating capacity at Hoover Dam by 15%.

Agencies in Nevada, Arizona and other states are launching water-saving construction projects. With 8,000 new residents a month, the Las Vegas Valley is squeezed by growing demand and dwindling supplies. Barnard of Nevada Inc., Las Vegas, recently finished a $6.4-million, 180-ft-long water intake extension at Lake Mead for Southern Nevada Water Authority (ENR 5/10 p. 7).

Despite conservation measures, Las Vegas may still have to declare a drought emergency by year’s end if Lake Mead’s water level continues to drop. SNWA is now considering plans that include drilling wells and building a $1-billion pipeline to tap rivers and groundwater from neighboring rural counties.

Salt River Project, a Tempe-based public utility that supplies 60% of Phoenix’s water, has been forced to cut deliveries to the city by one-third since January 2003. SRP is teaming with three cities on the new $13-million, 200-acre Agua Fria River recharge facility, west of Phoenix. It should be advertised in the fall of 2005, says Mario R. Lluria, SRP’s project manager.

North America’s largest design-build-operate water treatment plant is under construction near Phoenix. A team led by American Water Services Inc., Voorhees, N.J., with Black & Veatch, Kansas City, and McCarthy Building Cos. Inc., St. Louis, landed the $336-million fixed-price contract for the Lake Pleasant water treatment plant. It will have an initial 80-mgd capacity.