Bureau of Reclamation Banner
Yakima Project
Cle Elum Dam
Project Links
Project History
Project Data
Contact Information
Related Facilities
Related Documents
Yakima Project Brochure (776 KB) (pdf)
Yakima Project History (79 KB) (pdf)
General Description| Plan| Development| Benefits

General Description

The Yakima Project provides irrigation water for a comparatively narrow strip of fertile land that extends for 175 miles on both sides of the Yakima River in south-central Washington. The irrigable lands presently being served total approximately 464,000 acres.

There are seven divisions in the project: Storage, Kittitas, Tieton, Sunnyside, Roza, Kennewick, and Wapato. The Wapato Division is operated by the Bureau of Indian Affairs, but receives most of its water supply from the Yakima Project for irrigation of 136,000 acres of land. Over 45,000 acres not included in the seven divisions are irrigated by private interests under water supply contracts with the Bureau of Reclamation. Storage dams and reservoirs on the project are Bumping Lake, Clear Creek, Tieton, Cle Elum, Kachess, and Keechelus. Other project features are 5 diversion dams, canals, laterals, pumping plants, drains, 3 powerplants, and transmission lines.

Return to top


Irrigation water for the approximately 59,000 acres of land in the Kittitas Division is diverted from the Yakima River into the Main Canal by the Easton Diversion Dam near Easton, Wash. The Main Canal carries the water along the south side of the river to a point near Thorp, where it divides into the North and South Branches. The North Branch Canal crosses the Yakima River through a siphon to irrigate land lying on the north side of the river, while the South Branch Canal continues generally southeast from the point of division to irrigate lands lying on the south side of the river.

The Tieton Division includes nearly 28,000 acres of land lying west of the city of Yakima between the Naches River and Ahtanum Creek. Irrigation water for the lands in this division is diverted from the Tieton River by the Tieton Diversion Dam, about 8 miles downstream from Rimrock Lake. The diversions flow through Tieton Main Canal and, after supplying the distribution system of the Tieton Division, drain into Ahtanum Creek about 14 miles west of Union Gap.

The Sunnyside Division consists of some 103,000 acres of land lying mostly north of the Yakima River, and extends from the Sunnyside Diversion Dam, on the Yakima River near Parker, to the vicinity of Benton City. Water is diverted from the Yakima River by the Sunnyside Diversion Dam and flows generally southeast through the Sunnyside Canal, which supplies the distribution system of the division. Four irrigation districts in the Sunnyside Division pump water to their lands by hydraulic turbine pumps at drops on the Sunnyside Canal.

The Roza Division, a unit containing approximately 72,500 acres of land north of the Yakima River, extends from the vicinity of Pomona to a point north of Benton City. The distribution system is supplied by the Roza Canal, which originates at the Roza Diversion Dam on the Yakima River about 10 miles north of Yakima. The Roza Powerplant is adjacent to the Roza Canal, 3 miles from Yakima.

The Kennewick Division is a combined irrigation and power development. It includes the 12,000-kilowatt Chandler Powerplant and over 19,000 acres of irrigable land, of which some 4,600 acres are in the Kennewick Highlands and have been irrigated for many years. All of the lands receive a full water supply.

The Storage Division has supervision over the entire Yakima River water supply, both natural riverflow and the stored water in six reservoirs. The reservoirs have a total active capacity of 1,065,400 acre-feet.

Facility Descriptions

Bumping Lake Dam and Bumping Lake

Bumping Lake Dam is an earthfill structure on the Bumping River about 29 miles northwest of Naches. The dam, completed in 1910, is 60 feet high and contains 253,000 cubic yards of material. In 1973, the road crossing the spillway was replaced and a new concrete T-beam bridge was installed to replace a wood-truss bridge. Situated at the lower end of a natural lake, the dam formed a reservoir with an active capacity of 33,700 acre-feet constructed over a natural lake having unknown dead storage capacity.

Modifications to Bumping Lake Dam were undertaken in 1994-1997 under the Bureau of Reclamation's Safety of Dams Program. These modifications included the installation of an interceptor drain at the downstream toe of the dam, construction of downstream and upstream stability berms, replacement of the concrete spillway, installation of a steel liner in the outlet tunnel, and replacement of the outlet channel lining. The outlet gates, gate house, and gate operators were replaced in the early 1990's.

Kachess Dam and Kachess Lake

Kachess Dam is an earthfill structure located on the Kachess River about 2 miles northwest of Easton. This dam, 115 feet high with a volume of 200,000 cubic yards, also was built at the lower end of a natural lake, and created a reservoir with an active capacity of 239,000 acre-feet constructed over a natural lake having unknown dead storage capacity.

The discharge channel for Kachess Reservoir is 2,877 feet long and was constructed from the natural lake to the intake structure of the dam's outlet works. This was done so the natural lake could be used for storage. The first 1,182 feet consists of an open cut inlet channel leading to a 9 foot diameter tunnel for 1,393 feet and then 302 feet of open channel to the intake structure. Significant siltation had occurred in the discharge channel causing a restriction in passing the necessary water downstream.

In 1996, sediment was removed from the inlet channel and a new channel was excavated along the existing tunnel. In addition, a new intake structure was constructed, the steel bridge from the dam to the intake structure replaced, and the outlet works conduit lined with a minimum of 4-inch thick reinforced concrete overlay. The channel improvements were accomplished under Phase II of the Yakima River Basin Water Enhancement Project; Title XII of the Act of October 31, 1994. The intake structure and outlet conduit work was done as a part of the Bureau of Reclamation's Operations and Maintenance Modifications Program.

Keechelus Dam and Keechelus Lake

Keechelus Dam was constructed at the lower end of a natural lake and is on the Yakima River 10 miles northwest of Easton. This earthfill structure, completed in 1917, is 128 feet high and contains 684,000 cubic yards of material. Keechelus Lake has an active capacity of 157,900 acre-feet constructed over a natural lake having unknown dead storage capacity. Total rehabilitation of the outlet works and control tower was started in 1976. The two original cylinder gates were replaced by a single 8.5-foot-square hydraulically operated slide gate, and a new concrete chute and stilling basin that is 156 feet long, 18 feet wide, up to 28 feet deep was constructed. The concrete outlet conduit was partially lined with reinforced concrete, and a 22-inch-diameter pipe was installed in the outlet conduit to bypass minimum flows for fishery and stream enhancement when the outlet gates are closed.

In mid-1998, it was determined that dam safety deficiencies existed at Keechelus Dam due to the potential for dam failure from piping and/or internal erosion of embankment materials. A reservoir operating restriction to elevation 2510 feet was imposed together with increased monitoring and surveillance pending implementation of corrective actions. This operating restriction limited storage to 140,920 acre-feet. The reservoir could be operated above elevation 2510 feet for the control of large flood events. Modifications were performed on the dam between April 2002 and November 2003 under Reclamation's Safety of Dams Program. Modifications included removing and rebuilding much of the dam cross-section to include embankment zones and drainage features, construction of a bentonite slurry cutoff wall in the right abutment, and construction of a downstream drain along the entire length of the dam - all to control seepage and prevent internal erosion of the new structure. The reservoir operating restriction was lifted in early 2004 

Clear Creek Dam and Clear Lake

Clear Creek Dam, a concrete thin-arch structure on the North Fork of the Tieton River about 30 miles southwest of Naches and 48 miles west of Yakima, creates a reservoir with an active capacity of 5,300 acre-feet. The dam is 83 feet high and contains 5,800 cubic yards of concrete. Originally constructed in 1914, the dam was raised 21 feet in 1918 to its present height. Rehabilitation work in 1964 consisted primarily of placing new concrete in the arch section between elevation 2,991.0 and the crest, repairing cracks and poorly consolidated concrete with neoprene and epoxies, and installing protective wire-mesh fences from the abutments to upstream areas.

As the result of investigations conducted in 1987-1989, the Bureau of Reclamation concluded there were horizontal bands of deteriorated concrete in the section replaced in 1964. These conditions could result in sudden failure of the dam. The water level of Clear Lake was immediately lowered to reduce the likelihood of dam failure. Early in 1990, two holes were cut through the dam to further drain the lake to a point that only 230 acre-feet could be stored.

Overwhelming public support was expressed for reconstructing the dam and returning Clear Lake to its original condition, due mostly to the loss of recreational value. Reconstruction was accomplished through local, State, and Federal funding and consisted of converting the dam into a gravity structure by buttressing the arch with a new concrete section immediately downstream. A new 48-inch outlet conduit was installed near the elevation of the breach (2956.5 feet) to permit discharge whenever the lake was below the spillway crest. Clear Lake is now used primarily for recreation and most of the discharge is by the spillway.

Tieton Dam and Rimrock Lake

On the Tieton River about 40 miles west of Yakima, Tieton Dam is an earthfill structure with a concrete core wall that extends from the crest to about 100 feet below the riverbed. The dam is 319 feet high and contains 2,049,000 cubic yards of material. The reservoirs active capacity is 198,000 acre-feet.

Cle Elum Dam and Lake

Cle Elum Dam, on the Cle Elum River 10 miles northwest of Cle Elum, is an earthfill dam constructed at the end of a natural lake that forms a reservoir with an active capacity of 436,900 acre-feet. The dam is 165 feet high and, including the dikes, contains 1,411,000 cubic yards of material.

The outlet works of Cle Elum Dam were modified in 1977-1979 under the Bureau of Reclamation's Safety of Dams Program.

Roza Diversion Dam

Roza Diversion Dam located 10 miles north of Yakima, diverts water from the Yakima River for irrigation and power. The dam is a concrete weir, movable crest structure, 486 feet long at the crest, 67 feet high, and contains 21,700 cubic yards of concrete.

Easton Diversion Dam

Easton Diversion Dam located on the Yakima River near Easton, is a concrete gravity ogee weir, movable crest structure. This dam is 66 feet high and contains 5,800 cubic yards of concrete.

Other Diversion Dams

Sunnyside Diversion Dam, on the Yakima River near Parker, is an 8-foot-high concrete weir with an embankment wing. Tieton Diversion Dam, on the Tieton River about 16 miles southwest of Naches, is a 5-foot-high concrete weir, flanked by an embankment wing. Prosser Diversion Dam, on the Yakima River near Prosser, is a 9-foot-high concrete weir.

Intensive Federal, State, tribal, and local efforts in conjunction with the Northwest Power Planning Council resulted in Congress authorizing implementation of Phase I of the Yakima River Basin Water Enhancement Project in 1984. The purpose of Phase I is to reduce anadromous fish mortality at outdated fish ladders at diversion dams and inadequate fish screens at diversion canals. Ladders and screens at the largest diversion dams and canals were completed in 1989 and a similar Phase II program is underway at the smaller diversions.

Chandler Powerplant

The Chandler Powerplant develops 12,000 kilowatts, which are delivered to the Bonneville Power Administration.

Roza Powerplant

More than 70 miles of transmission lines deliver power to pumping plants in the Roza Division. The Roza Powerplant develops 12,937 kilowatts.

Canal and Drainage Systems

Main canals and laterals deliver water to the project lands. The canals vary in capacity from 347 cubic feet per second in Tieton Canal to 2,200 cubic feet per second in Roza Canal. Over 140 miles of drains make up the drainage system.

Replacement of the entire 320-mile distribution system of the Tieton Division was completed in 1986 by the Yakima-Tieton Irrigation District with 210 miles of a closed pipe pressure system, enabling about 85 percent of their service area to receive gravity pressure service. The remaining 15 percent of the area is provided pressure service by three small pumping plants.

A reregulating dam, French Canyon Dam, with a total capacity of 670 acre-feet (active 645 acre-feet) was constructed at the terminus of the main conveyance flume which carries water for 12 miles from the Tieton River diversion. Two small hydroelectric generating plants of 2,100 kilowatts were also constructed to provide power for the pumping plants.

Water conservation measures have also been implemented by many of the irrigation entities in the Yakima Project with funding provided in part by the State of Washington. Improvements to water delivery systems are expected to continue with Federal and State funding to be provided from the Yakima River Basin Water Conservation Program, a part of Phase II of the Yakima River Basin Water Enhancement Project authorized by Congress in 1994.

Pumping Plants

The project has 30 pumping plants varying in capacity from 500 cubic feet per second at Chandler to 1.56 cubic feet per second at Hillcrest.

Under a rehabilitation and betterment agreement, the Bureau of Reclamation installed a pumping plant and intake canal for the Cascade Irrigation District during 1974-1975. The plant has eight units with a total capacity of 160 cubic feet per second and a dynamic head of 108 feet. The 1.3-mile-long Cascade Intake Canal diverts Yakima River water to the pumping plant that delivers the water through a 300-foot-long discharge line to the portal of Tunnel No. 7 on the Cascade Irrigation District Canal.

Operating Agencies

The Kittitas Division is operated by the Kittitas Reclamation District, the Roza Division by the Roza Irrigation District, the Kennewick Division by the Kennewick Irrigation District, and the Tieton Division by the Yakima-Tieton Irrigation District. The major features of the Sunnyside Division distribution system are operated by the Sunnyside Valley Irrigation District and the Board of Control. The Storage Division is operated by the Bureau of Reclamation. Pumping plants and laterals serving the smaller districts are operated and maintained by those districts. Laterals of 10 cubic feet per second or less usually are maintained by the water users. The Wapato Division is operated by the Bureau of Indian Affairs.

Return to top



The first settlers came to the Yakima Valley in about 1860. They were cattlemen attracted by the abundance of bunch grass and wild game, and the fertile bottom lands. The first irrigation ditch of record was constructed in 1864. The ditch conveyed water from Ahtanum Creek for irrigation of a small garden above the Catholic mission.

Hops were first raised in 1872, and alfalfa was successfully grown in 1881. Private canal companies were formed along the river, and successfully irrigated a large area. Construction of the Northern Pacific Railway into the valley in 1886 gave greater impetus to irrigation development.


As a result of a petition dated January 28, 1903, from citizens of Yakima County to the Secretary of the Interior presenting the very favorable opportunities for construction and development, investigations were initiated which led to the beginning of construction by the Reclamation Service. The Sunnyside and Tieton Units were approved for construction in 1905. Early in 1906, investigation of storage sites was initiated, including Bumping Lake, McAllister Meadows (Tieton Reservoir), and Cle Elum, Kachess, and Keechelus Lakes.

Studies on a proposed Bumping Lake Enlargement dating back to the mid-1960`s were issued in a March 1976 report prepared by the Bureau of Reclamation and the Fish and Wildlife Service. These studies centered on a proposal to construct a new dam on Bumping River about 4,500 feet downstream from the existing Bumping Lake Dam that would impound 458,000 acre-feet of water. Benefits from the proposed additional storage would include fish resource enhancement, supplemental irrigation, flood control, and recreation.

In 1979, Congress authorized a feasibility to address the water resource needs of the Yakima River basin; the Act of December 12, 1979 (93 Stat. 1241, Public Law 96-162). An outgrowth of this study was the implementation of Phase I (fish ladders and fish screens) and Phase II (water conservation and other measures) of the Yakima River Basin Water Enhancement Project.


The Tieton Division and the Sunnyside Division were recommended for construction by the Director, United States Geological Survey on October 24, 1905, and November 8, 1905, respectively. Construction of these divisions was authorized by the Secretary of the Interior on December 12, 1905, pursuant to the Reclamation Act of 1902 (32 Stat. 388).

The Benton Division, incorporated as a part of the Sunnyside Division, and the Kittitas and Wapato were reported on by a Board of the Army Engineers and approved by the President on June 5, 1911, under section 4 of the Act of June 25, 1910 (36 Stat. 935). Appropriations for the Kittitas Division were contained in the Department of Interior Appropriations, 1926, the Act of March 3, 1925 (43 Stat. 1141, Public Law 68-580).

The Department of Interior Appropriations, 1931, the Act of May 14, 1930 (46 Stat. 279, Public Law 71-217) appropriated funds for the construction of the Kennewick Highlands Project. A finding of feasibility was made on this project by the Secretary of the Interior on March 6, 1931 pursuant to subsection B of section 4 of the Act of December 5, 1924 (435 Stat. 672) and approved by the President on March 7, 1931, pursuant to section 4 of the Act of June 25, 1910 (36 Stat. 835). The Kennewick Division, which included the Kennewick Highlands Project, was authorized by the Act of June 12, 1948 (62 Stat. 382, Public Law 80-629).

The Roza Division was found feasible by the Secretary of the Interior on November 1, 1935, under subsection B of the Act of December 5, 1924 (43 Stat. 672) and approved by the President on November 6, 1935, under section 4 of the Act of June 25, 1910 (36 Stat. 835).

The Kennewick Division Extension was authorized on August 25, 1969 (83 Stat. 106, Public Law 91-66) but has been indefinitely deferred. Cascade Irrigation District rehabilitation and betterment work was authorized by Public Works Appropriation Act dated October 7, 1970 (84 Stat. 896, Public Law 91-439). Replacement of the Tieton Division's distribution system was accomplished under authority of the Rehabilitation and Betterment Act of October 7, 1949 (63 Stat. 701, Public Law 81-335). Pursuant to the provisions of the Budget Reconciliation Act of 1987, the Yakima-Tieton Irrigation District repaid the discounted loan in July 1988. Title to the rehabilitated facilities was retained by the United States.

Phase I of the Yakima River Basin Water Enhancement Project, the construction of fish ladders and fish screens at diversion dams and diversion canals, was authorized by the Act of August 17, 1984 (98 Stat. 1333, Public Law 98-381) and the Act of August 22, 1984 (98 Stat. 1379, Public Law 98-396).

Phase II of the Yakima River Basin Water Enhancement Project was authorized by Title XII of the Act of October 31, 1994 (108 Stat. 4550, Public Law 103-434). Phase II measures include, among other things, the Yakima River Basin Water Conservation Program providing authority to appropriate funds for the acquisition of water for fish and wildlife and for measures to improve the efficiency of water delivery and use so instream flows for fish and the reliability of the irrigation supply is improved. Also, Phase II provides for a new operating regime for the Yakima Project of specified instream target flows over Sunnyside and Prosser Diversion Dams during April through October of each year in relation to the total water supply available. This new operating regime was initiated in 1995.

The original purpose of the Tieton, Sunnyside, Wapato, Kittitas, and Roza Divisions, as well as the Storage Division, was irrigation. The Kennewick Division was authorized for irrigation, hydroelectric generation, and the preservation and propagation of fish and wildlife. The fish and wildlife purpose is associated with fish screens in the Chandler Canal and fish ladders at Prosser Diversion Dam.

Title XII of the Act of October 31, 1994 authorized fish, wildlife, and recreation as additional purposes of the Yakima Project. These purposes however, shall not impair the operation of the Yakima Project to provide water for irrigation purposes nor impact existing contracts.


Construction of the Tieton and Sunnyside Units began in 1906. The first water for irrigation of project lands was available for the 1907 season, and on October 17, 1907, the Sunnyside Diversion Dam was completed. Development of the project progressed with the construction of Tieton Diversion Dam in 1908, Bumping Lake Dam in 1910, Kachess Dam in 1912, Clear Creek Dam in 1914, Keechelus Dam in 1917, Tieton (storage) Dam in 1925, Easton Dam in 1929, Prosser Powerplant in 1932, Cle Elum Dam in 1933, Roza Diversion Dam in 1939, and Chandler Powerplant in 1956. Distribution systems were built concurrently with the storage and diversion facilities. Prosser Powerplant was retired in 1955, and Roza Powerplant was completed in 1958. Construction of Kennewick Division facilities began in January 1953, and were completed in January 1958. Cascade Irrigation District rehabilitation and betterment work began February 1974 and was completed in May 1975.

Construction of the Phase I fish ladders and fish screens at the larger diversion dams and diversion canals began in 1984 and were completed in 1989. Implementation of Phase II water conservation and other measures is pending completion of funding prerequisites.

Return to top



The record of crop production on the Yakima Project is outstanding. Nearly one-half million acres of sage-covered lands have been transformed into one of the richest agricultural areas in the Nation. Yakima County ranks first among all counties of the United States in the production of apples, mint, and hops. Principal crops are fruit, vegetables, forage, hops, and mint.


Bumping, Rimrock, and Clear Lakes are in Snoqualmie National Forest. The rugged mountain terrain, Surrounded by coniferous forests, creates magnificent scenic settings. Cabins, camping, boating, and fishing are available at Bumping Lake. Much of the shoreland at Clear Lake is reserved for group camp use. Rimrock Lake is used intensively by fishermen and other recreationists. There are private cabins and several campgrounds. Good fishing is available in the reservoir for rainbow and other trout, and in the stream below the dam for rainbow trout and whitefish.

Cle Elum, Kachess, and Keechelus Reservoirs are in the Wenatchee National Forest. Cabins, camping, swimming, boating, picnicking, and fishing, primarily for trout and freshwater ling, are available at all three reservoirs. Since construction of the dams, fishing has improved greatly in the streams below the dams.

Sunnyside, Prosser, Roza, and Easton Dams on the Yakima River have recreation associated with their impoundments. Sunnyside is limited to sightseeing and fishing. Prosser and Roza diversions both provide excellent fisheries and Roza also has boat launching facilities.

The Easton Diversion Dam area is much larger than the other three as it has 112 acres of land and 240 acres of water surface. There is a State park that provides facilities for camping, swimming, and boat launching and mooring. Recreational use is heavy; the reservoir also has a good fishery.

Hydroelectric Power

The project has an installed generating capacity of 24,937 kilowatts. Much of the power produced is used for pumping irrigation water; the surplus is marketed by the Bonneville Power Administration, as a part of the Columbia River Federal Power System.

Flood Control

To the extent possible, given the amount of basin runoff above the reservoirs, the storage capacity at the reservoirs, and the outlet capacities of the reservoirs, the Yakima Project attempts to control runoff to below damaging levels.

Dam and reservoirAccumulated actual benefits 1950-2009 ($1,000)Capacity assigned to flood control function (acre-feet)
Yakima Project389,600 
 Keechelus 158,000
 Kachess 239,000
 Cle Elum 437,000
 Bumping Lake 34,000
 Tieton 198,000

Return to top

Last updated: Jan 03, 2013