Annual Report of the Chief of Engineers
on Civil Works Activities
Fiscal Year 1973
Department of the Army Corps of Engineers
Extract Report of Walla Walla District
Ice Harbor Lock and Dam - Lake Sacajawea, Washington
Location. On Snake River, 9.7 miles above river mouth at head of Lake Wallula and 12 miles east of Pasco, Washington.
Existing project. A dam, powerplant, navigation lock, fish ladders, appurtenant facilities, and relocation of railroads. Project provides for navigation, hydroelectric power generation, and incidental irrigation. Dam has normal operating range between elevations 440 and 437 Mean Sea Level (MSL). The lake extends upstream about 31.9 miles and provides slackwater to Lower Monumental Lock and Dam. Structure is about 2,700 feet long and about 130 feet high above streambed. Beginning at south end, project consists of a concrete non-overflow section, concrete powerhouse, spillway dam, navigation lock, and an earth and rockfill embankment at north abutment. Fish-passing facilities, including two ladders, are provided. Powerplant now has three 90,000-kilowatt units and three 111,000-kilowatt generating units are being installed. Spillway dam is 610 feet long, and overflow crest at elevation 391 MSL is surmounted by 10 radial gates, 50 feet wide by 51 feet high, which provide the capacity to pass a design flood of 850,000 cubic feet per second. Deck is at elevation 453 MSL, and provides a service road and track for a gantry crane. Navigation lock is single-lift type, with clear plan dimensions of 86 by 665 feet and 15-foot minimum depth over the sills. A navigation channel 250 feet wide and 15 feet deep is provided from the mouth of the Snake River to the dam. Principal data are set forth in table 39-G.
Existing project authorized by 1945 River and Harbor Act, based on plans in H. Doc. 704, 75th Cong., 3d Sess. Estimated cost for new work (July 1973) is $169,981,800, consisting of $129,600,000 for the completed project, $34,800,000 for power units 4 through 6, $87,000 for U.S. Coast Guard navigation aids, $22,300 for value of public-domain lands, $5,390,000 for recreational facilities, and a non-Federal contribution of $82,500 toward an artificial fish spawning channel.
Local cooperation. None required.
Operations and results during fiscal year. New work: Deferred construction along the realignment of the Union Pacific Railroad was completed March 1973 following a modification tot he agreement with the company. Work is continuing on a contract for turbines for power generating units 4 through 6. Contracts were awarded in July 1972 for the generators for power units 4 through 6, in October 1972 for power transformers, and in April 1973 for recreation facilities at Charbonneau Park.
Operation and Maintenance: Normal operation and maintenance of navigation lock, fish passage, recreation facilities, and powerplant continued, and 2,123,000 megawatt hours of electric energy were delivered to Bonneville Power Administration, the marketing agency. A total of 1,353,792 tons of grain and miscellaneous cargo passed through the navigation lock during calendar year 1972.
Condition at end of fiscal year. Construction started December 1955 and the project was placed in useful operation January 1962. Installation of power units 4 through 6 is 28 percent complete. The entire project, including installation of the additional power units, is 83 percent complete.
An Environmental Impact Statement concerning power units 4 through 6 was filed with the Council on Environmental Quality August 1971.
Since the first power generating unit went on the line in December 1961, the project has delivered 22,822,000 megawatt hours of electric energy to Bonneville Power Administration.