Expert Report of D. Randolph Seahom and Exhibits

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• Consumptive Uses and Losses 5 Lesser structures downstream include Senator Wash, Laguna, Headgate Rock, Palo Verde, Imperial, and Morelos Dams. Senator Wash and Laguna Dams provide very limited amounts of reregulation capacity, while the others are used principally for diversions. Diversions below Lake Mead for agriculture, municipal and industrial, power, export, and other purposes are of the magnitude of six million acre -feet annually. A portion of these diversions is satisfied from upstream return flows. Yuma and Lake Havasu City in Arizona and Needles and Blythe in California are the major cities along the main stem below Lake Mead. Current irrigated lands adjacent to the main stem are estimated to cover approximately 275,000 acres. Tributary Area Above Lake Mead, Arizona - Nevada -Utah Development away from the Colorado River main stem is limited by the availability of water and the rugged terrain. Most of the irrigated lands in this area are located in the lower reach of the Virgin River and Las Vegas Valley in Nevada, on Kanab Creek in Arizona and Utah. Reporting period irrigated land averaged approximately 12,500 acres. North Las Vegas, Las Vegas, Henderson, and Boulder City in Nevada, are the leading cities in the area. 0 Tributary Area Below Lake Mead, Arizona As discussed above, development away from the Colorado River main stem is limited by the availability of water and the rugged terrain. Most of the irrigated lands in this area are located in the lower portions of the Gila and Bill Williams Rivers in Arizona. Kingman and Williams in Arizona, are the leading cities. Little Colorado River, Arizona -New Mexico The Little Colorado River drainage area occupies a large part of northern Arizona and a portion of west - central New Mexico. It originates on the north slopes of the White Mountains about 20 miles above Springerville, Arizona. The river has a main stem length of about 356 miles and joins the Colorado River on the east boundary of Grand Canyon National Park about 78 miles downstream from Glen Canyon Dam. A series of saline springs near the mouth of the Little Colorado River produces an estimated 160,000 acre -feet of water annually. The U.S. Geological Survey (USGS) gauging station near Cameron, Arizona, is located on the Navajo Indian Reservation about 45 miles upstream from the mouth. Streamflow is undependable and erratic and is subject to flash floods of considerable magnitude. Flow at the gauging station during the 1996 -2000 period varied from 16,990 acre -feet in 1996 to 138,000 acre -feet in 1998. Only minor development of the ground water has occurred because of low yields and poor quality. Excessive erosion and sediment deposition plague the area.