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Show Boulder Reservoir Largest In World The reservoir at Boulder dam on July 22, 1935, became the world's largest hand-made lake. On that date the reservoir was 286 feet deep, .84 miles long, and held a total of 1,453,915,000,000 gallons of water or 4,450,000 acre-feet, acre-feet, at the last reading at Boulder Boul-der City and' the lake will continue to grow for months. The Assuan reservoir on the . Nile in Egypt, which held the position of . the largest artificial lake, with a capacity of 1,322,955,-000,000 1,322,955,-000,000 gallons, has been surpassed. surpass-ed. "' '; The gates at Boulder dam were closed five, months ago, but no effort ef-fort was made to retain all the water in excess of that needed for irrigation below the dam site in the reservoir. Despite a large discharge, dis-charge, however, the reservoir has filled to about one-seventh of its total capacity, 30,500,000 acre-feet. acre-feet. . ' Since the gates were closed at the dam early this year, harnessing harness-ing the mig-hty resources of the Colorado river and putting Boulder Boul-der dam- to work, the project has been storing up. . dividends it will repay in the future in the form of. power and water. The reservoir already is deeper ; than Lake Erie, which has a maximum maxi-mum depth of ' 210 feet. Boulder dam eventually will raise the surface sur-face of the river 582 feet. The reservoir, is 12 miles wide at the old Virgin river wash about 30 miles up the river from the ;., dam. While the reservoir has reached a point only 31 miles from its maximum length up the canyons can-yons of the Colorado, is still has far to go to reach its maximum capacity. The sharper fall in the mile-deep segment of the lower Grand canyon will permit the adding add-ing of only short distances to its length, despite tremendous increases in-creases in the amount of water held. The water is backed up through Boulder, Virgin, and Iceberg can- I (Continued on last page) ' o Boulder Reservoir (Continued from first page.) i yons and into the Grand canyon, covering many an old rapid which prevented navigation oi' the stream. It now would be possible to enter a boat at Pierce's Ferry between St. Thomas. Nevada, and Hackberry, Arizona, and sail on still waters to the dam about SO miles downstream. Boulder dam already has fulfilled ful-filled one of its major objectives. It has removed the threat of flood and drouth forever from the Palo Verde, Yuma and Imperial valleys. Last year the river went dry in July and crop damage estimated at $10,000,000 resulted in Imperial valley. This spring a peak flood of 105,000 second-feet of water was recorded in the Colorado at Grand canyon, all of which was caught by. Boulder dam. A flood of that magnitude would have presented a very real threat to the levee system of the Imperial valley had the; river remained uncontrolled, since the drouth has cracked the levees in many places. The amount of water already held in the Boulder reservoir would supply all the needs below the dam for more than a year. More than half of the present inflow of 20.000 second-feet is being allowed to pass tho dam. Because of certain construction work still under way the water level was not permitted to rise rapidly this year. The Reclamation Reclama-tion Era. o |