- Projects & Facilities
- Wapinitia Project
Region: Columbia-Pacific Northwest Region
Wapinitia Project History (37 KB)
The Wapinitia Project, Juniper Division, is on Juniper Flat in north-central Oregon. Juniper Flat is a plateau, 3 to 6 miles wide and approximately 17 miles long, between the Deschutes and White Rivers. Some 2,100 acres over a scattered area receive supplemental irrigation service from the project. The principal construction feature is Wasco Dam on Clear Creek, 0.5 mile below the outlet of Clear Lake, a natural lake in a mountain valley.
Many of the early immigrants to the West settled in the White River Basin. Demands of the increasing population in Oregon and Washington led to the establishment of large grazing herds. Extensive dryland wheat farming, following completion of the transcontinental railroad in 1880, later complemented the livestock industry. Some of the large sheep and cattle herds were gradually broken up, and thousands of acres, once used as rangeland, were homesteaded and brought under cultivation. Years of above-average rainfall promoted a wheat boom. Succeeding years of very low rainfall forced the abandonment of many farms. The farmers who stayed diverted water for irrigation to grow alfalfa. However, irrigation developed slowly due to limited financial means, limited surface water supplies, and costly facilities.
The first investigation of irrigation possibilities in the area was made in 1910. The primary considerations of this investigation were to provide storage on Clear Lake and construct a V-shaped flume to transport logs to a sawmill 6.5 miles downstream. A supplementary purpose of the investigation was to determine the practicability of furnishing irrigation water to lands on Juniper Flat. A report prepared in 1916 by the Reclamation Service and the State Engineer contained reconnaissance information on the general area and indicated some 46,000 acres as potentially irrigable, contingent upon storage in Clear Lake, diversion of White River water, and purchase or control of the White River Powerplant. An unpublished report on the White River Basin was made by the Bureau of Reclamation in 1945, based essentially upon the same considerations as the 1916 report. A more detailed investigation, begun in the summer of 1952, was made to find means of stabilizing the water supply for lands under the Juniper Flat District Improvement Company. The report of this investigation was the basis for congressional authorization of the project.
The Juniper Division of the Wapinitia Project was authorized was authorized by Congress by the Act of June 4, 1956 (70 Stat. 244, Public Law 84-559). The authorized project purpose is irrigation. Construction of minimum basic recreation facilities was also authorized.
The contract for construction of Wasco Dam was awarded in May 1958, and the completed structure was accepted by the Bureau of Reclamation in November 1959.
Stored irrigation water has made possible the production of crops every year in an area that previously produced good crops only during infrequent wet years. Irrigated pasture, hay, and wheat are the principal crops.
Clear Lake as a natural lake was a popular recreation center. Construction of Wasco Dam increased the surface area to 557 acres and provided 8 miles of shoreline. There are 1,374 acres of land surrounding the lake that are available for recreation. Located entirely within the Mt. Hood National Forest, the lake is about 13 miles south of Mt. Hood and lies in a small, forested valley. Recreation facilities for camping and boat launching are available, and the lake has a very good trout fishery.
Project water is stored in Clear Lake behind Wasco Dam, about 35 miles west of Maupin, Oregon. Existing diversion structures, canals, and other distribution facilities that were formerly in operation have been used without rehabilitation or extension by the project. A diversion structure on Clear Creek, located about 3 miles downstream from Wasco Dam, diverts the water into a delivery canal, through which it is conveyed about 12 miles to be discharged into McCubbin Gulch. After flowing about 4 miles down the gulch, the water is rediverted into the distribution system. The main distribution canal extends the full length of Juniper Flat north of Wapinitia Creek. Two smaller canals with separate diversions from McCubbin Gulch serve a small area south of Wapinitia Creek.
Wasco Dam is a 59-foot-high zoned earthfill structure that contains 57,000 cubic yards of material. The crest is 20 feet wide and 415 feet long. The reservoir behind the dam has a total capacity of 13,100 acre-feet (active 11,900 acre-feet) and a surface area of 557 acres. The outlet works consists of 20-foot-wide approach and outlet channels, a submerged vertical intake structure, a single rectangular 4- by 5-foot conduit, a gate chamber with two 3-foot-square slide gates and two overflow weirs, and a 56-foot-long stilling basin. The slide gates are operated manually by two lifts on top of the gate chamber structure at the crest of the dam. The emergency spillway, crossing the left abutment, consists of an unlined channel with a base width of 30 feet. A concrete overflow grade wall is in the spillway 10 feet upstream of the axis of the dam.
In October 1997, a restriction limiting reservoir operation to elevation 3505.0 feet was imposed due to seepage on the face of the dam which occurs above this elevation. This 9-foot restriction reduced the available reservoir capacity to 7,000 acre-feet. In the fall of 1999, a Safety of Dams repair was done on Wasco Dam. Work included modification of the gate structure, installation of a slurry trench, toe drain, inspection well and stabilization berm.
The project is operated and maintained by the Juniper Flat District Improvement Company.
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OperatorTitle: Area Office Manager
Organization: Columbia-Cascades Area Office
Address: 1917 Marsh Road
City: Yakima, WA 98901-2058
OwnerTitle: Public Affairs Officer
Organization: Commissioner`s Office
Address: 1849 C Street NW
City: Washington, DC 20240