Page:Collier's New Encyclopedia v. 03.djvu/296

LEFT DAM 252 DAM built of concrete, 1,400 feet long, and 217 feet in height. The Noguera Pallaresa River Dam in Spain was built and designed by Ameri- can engineers. It is 330 feet high, 700 feet long, has a base width of 230 feet, and is built of concrete. The deep water plans for the Missis- sippi river include the construction of numerous dams, and in 1917 Dam No. 1, located near St. Paul, was placed in operation. It made the river available for navigation for 13 miles. In New South Wales the Murray River Dam has been planned as part of an irrigation project. It will be 3,600 feet long, and have both earth and con- crete sections. In 1864 a poorly constructed earth dam at Sheffield, England, went out the first time it was put to use, and caused a flood which cost 238 lives. No en- gineer was employed to design the Mill River Dam at Williamsburg, Mass., which went out in 1874, with a loss of 143 lives, and $1,000,000 in property. The ROOSEVELT DAM, ARIZONA The Hetch Hetchy Dam of the San Francisco water system will be one of the largest masonry dams in the world. The height from foundation base to crest will be 311 feet. It will be a masonry dam with a straight gravity section of 600 feet, and will have a siphon spillway. It will be located in the Tuolumne river 150 miles E. of San Francisco. South Fork Dam, owned by the South Fork Hunting and Fishing Club of Pittsburgh, Pa., was an earth dam of 70 feet height. It was designed to have a spillway of 150 feet, but this was not carried out, and the existing spillway was partially blocked with screens, bridge supports, etc., when in May, 1889, excessive rains caused the water to go over the entire length of the dam. The