HARNESSING A RIVER

Wairarapa Times-Age, 7 October 1943, Page 2

HARNESSING A RIVER

ACHIEVEMENT IN UNITED STATES DAMS ON THE COLORADO ROTARY CLUB ADDRESS “Harnessing the Colorado” was the subject of an informative address, given at today's luncheon of the Masterton Rotary Club by Mr W. V. Madden. The Colorado River, said Mr Madden, flowed for miles in deep canyons, the walls of which were often 4000 to 7000 feet high. It drained, an area of about 225,000 square miles, equal to times the total area of New Zealand. There were four major dams which harnessed the Colorado for irrigation, water supply and electrical energy. Two of them made water available to the southern portion of Calefornia foi- irrigation purposes. A third dam supplied, through the Colorado Aqueduct, one thousand million gallons of water daily to thirteen cities on the western seaboard. The aqueduct was 242 miles long, including 92 miles of tunnel, the longest 18 miles in length. Enormous pumps lifted the water to a height of 1617 feet in the first' 100 miles. No less than 2000 square miles of country were under cultivation in a region where oranges, lemons and other fruits now grew in profusion. / The largest project in the scheme for harnessing the Colorado River, said Mr Madden, was the Boulder Dam, built at a cost of about £40,000,000. This vast dam, rising 727 feet above bedrock, could hide Niagara Falls, with St. Paul’s Cathedral placed on top of them. The dam raised the water level of the Colorado by 584 feet. As much as 4,360,000 cubic yards of concrete, which contained 755,360 tons of cement, were poured into this huge dam. The temperature in the canyon was so high that steps had to be taken to cool the concrete mix as it was poured into the dam and in that connection 800,000 feet of pipe, through which ammonia was

compressed, were used for cooling purposes. It was calculated by engineers that the dam would have taken 200 years to build had the cooling of the' concrete mix been left to nature. The power house at the foot of the dam was designed to generate electrical energy to 4,333,000,000 kilowatt hours, this being equivalent to one-quarter of the total of the United Kingdom’s consumption in 1933. An inland sea 115 I miles in length and in places 40 miles | wide had been created by this dam. Floods and drought had their terror and man was able to regulate the flow of this mighty river, making available to many millions of people the benefits of agriculture and the supply of electrical energy for homes and industry.