Annual Report of the Chief of Engineers
on Civil Works Activities
Fiscal Year 1979
Department of the Army Corps of Engineers
Extract Report of Walla Walla District
McNary Lock and Dam--Lake Wallula, Oregon and Washington
Location. On Columbia River 292 miles above mouth, near Umatilla, Oregon, and 3 miles above mouth of Umatilla River.
Existing project. See table 39-B for authorizing legislation. Includes a concrete dam 7,300 feet long overall and 183 feet high above streambed, powerplant with 14 power generating units, navigation lock, fishways, levees and pumping plants, incidental irrigation, and modification and relocation of railroad bridges over the Columbia and Snake Rivers in order to eliminate hazards to navigation. Principal project data are set forth in table 39-H.
Estimated total cost for new work is $327,769,000 consisting of $319,200,000 (full funding) for construction, $69,000 for Coast Guard navigation aids, and $8,500,000 for modification of the Union Pacific Railroad Bridge over Columbia River by the Coast Guard. Expenditures on recreation facilities for completed project have been $1,130,114.
Local cooperation. None required.
Operations and results during fiscal year. Phase II of the navigation channel dredging contract was awarded. Phase II involves a three-year contract with a limited working period in the river of four months each year, due to migrating fish runs. The first year of the contract had reduced earnings due to severe winter weather conditions.
Operation and maintenance: Normal operation and maintenance of project continued. Contracts were awarded and completed for spare navigation lock gate pintle bearings, removal of navigation lock stairway building automatic generation control, cultural resource investigations, and recreation area maintenance. Approximately 6.40 billion kilowatt hours of electric energy were delivered to Bonneville Power Administration, the marketing agency. A total of 5,721,341 tons of commodities passed through the navigation lock during calendar year 1978.
Condition at end of fiscal year. Construction started May 1947, and is 100 percent complete except for modification of fish facilities and dredging of the upstream navigation channel. Project placed on permanent operating basis and lake raised to Elevation 340 in November 1953. Except for maintenance interruptions, all 14 power units have been in commercial operation since February 1957.
Power generation through September 1979 has been 150.25 billion kilowatt hours, representing a gross income of $224.2 million to the U.S. Treasury from sale of power by Bonneville Power Administration. A final Environmental Impact Statement was filed with Council on Environmental Quality in June 1976.