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General Description| Plan| Development| Benefits

General Description

The original Umatilla Project furnishes a full supply of irrigation water to over 17,000 acres and a supplemental supply to approximately 13,000 acres. These lands, located in north-central Oregon, are divided into three divisions. The East Division is the Hermiston Irrigation District, the West Division is the West Extension Irrigation District, and the South Division includes the Stanfield and Westland Irrigation Districts. In addition, there are approximately 3,800 acres not included in an irrigation district that are provided either a full or supplemental water supply from McKay Reservoir under individual storage contracts.

Project features of the East Division are Cold Springs Dam and Reservoir, Feed Canal Diversion Dam and Canal, and Maxwell Diversion Dam and Canal. Three Mile Falls Diversion Dam on the Umatilla River and the 27-mile West Extension Main Canal are the principal features of the West Division. McKay Dam and Reservoir are the only features in the South Division.

Activities were initiated in the mid-1980s under the Umatilla Basin Project to restore instream flows for anadromous fish and allow established irrigation to continue. These activities resulted in Umatilla River channel modifications, construction of fish ladders, fish traps and fish screens, and the construction of water exchange facilities (Phase I and Phase II) to deliver irrigation replacement water from the Columbia River.

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The original project plan provided for irrigation of lands in the lower Umatilla River Valley and along the south side of the Columbia River west of Umatilla, Oregon, with water from the Umatilla River. Storage is provided by Cold Springs Dam, to which water from the Umatilla River is conveyed through a feed canal, and by McKay Dam on McKay Creek. Three diversion dams on the Umatilla River divert into the Feed Canal, which supplies Cold Springs Reservoir, and into the West Extension and Maxwell Canals, each of which serve portions of the project lands.

Stanfield and Westland Irrigation Districts have each contracted for the storage space in McKay Reservoir. Some 71 individuals also have contracts for about 8 percent of the storage space. The remaining storage space is in a `reserved status` (15 percent), dedicated to exclusive flood control (8 percent), or not under contract (9 percent). The Bureau of Reclamation is not responsible for the distribution of the stored water since the districts operate their own canal systems.

Facility Descriptions

Unit descriptions and facilities

Facilities of the original plan are first described then new facilities for anadromous fishery enhancement are discussed. Some changes in sources of water supply resulted with construction of the new facilities.

Cold Springs Dam is a zoned earthfill type with a structural height of 115 feet and a volume of 793,000 cubic yards. Cold Springs Reservoir is located offstream about 6 miles northeast of Hermiston, Oregon. Water is diverted to the reservoir off-stream by the Feed Canal Diversion Dam and Canal. The reservoirs total active capacity is 39,260 acre-feet (active conservation of 38,646 acre-feet).

Safety of Dams work in 1994-1995 included the construction of an interceptor trench and drain at the downstream toe of the embankment, a downstream stability berm, extension of the wing dikes, replacement of the spillway with an enlarged roller compacted concrete structure, and a new Feed Canal backflow structure.

Located on McKay Creek about 6 miles south of Pendleton, Oregon, McKay Dam was constructed to furnish a supplementary supply of water to Stanfield and Westland Irrigation Districts. The dam is an earthfill structure with a reinforced concrete paved upstream slope, is 165 feet high, and contains 2,364,000 cubic yards of material. At closure in 1927 the reservoir had a total storage capacity of 73,800 acre-feet (active 73,800 acre-feet). In 1993, a sedimentation survey estimated the total reservoir storage capacity at 71,500 acre-feet (active conservation of 65,534 acre-feet).

McKay Dam was originally constructed during 1923-1927. Modification of the spillway section was made in 1978-1979 to increase the capacity from 10,000 to 27,000 cubic feet per second. In 1991, the needle valves were replaced with the new jet flow gates. Safety of Dams work on the left abutment included the excavation and replacement of low-strength foundation materials, construction of 700 feet of berms on the upstream and downstream sides, and the installation of a drainage system.

Feed Canal Diversion Dam

The Feed Canal Diversion Dam is located on the Umatilla River 1.5 miles southeast of Echo, Oregon. The dam, a concrete, rock, and timber weir with an embankment wing, raises the level of the water in the riverbed 4 feet to provide diversion into the 25-mile-long Feed Canal (maximum operational capability of 220 cubic feet per second) that extends to the Cold Springs Reservoir. This canal and the reservoir originally provided water for late summer releases from the dam.

Maxwell Diversion Dam

The Maxwell Diversion Dam and Canal divert water from the Umatilla River and convey it to lands in the East Division. The dam, located about 1 mile west of Hinkle, Oregon, is a concrete and timber-crib weir with an embankment wing. The dam permits diversion into the Maxwell Canal by raising the water surface 4 feet above the riverbed. The canal is 10 miles long and has an initial capacity of 140 cubic feet per second.

The Three Mile Falls Diversion Dam is a concrete multiple arch weir which diverts water to the West Division through the West Extension Main Canal. The dam is on the Umatilla River 3 miles south of Umatilla, Oregon, and has a structural height of 24 feet, a hydraulic height of 23 feet, and a crest length of 915 feet. The canal is 27 miles long and has a diversion capacity of 375 cubic feet per second.

River Pumping Plant

The West Extension Irrigation District installed the River Pumping Plant in 1968-69 to supply supplemental irrigation water to lands within the district and to serve an additional 2,000 acres outside the West Extension irrigable area. The plant is located on the Umatilla River 0.5 mile above its confluence with the Columbia River and discharges into the West Extension Main Canal 3 miles from Three Mile Falls Diversion Dam. Three vertical-turbine pumps, rated at 20 cubic feet per second each and driven by 600-horsepower motors, are installed in the plant.

New Facilities for Anadromous Fishery Enhancement

Anadromous fish passage in the Umatilla River from Three Mile Falls Diversion Dam to the mouth was improved with the excavation of a low flow fish passage channel by the Corps of Engineers in 1986. The Bureau of Reclamation constructed fish ladders and traps at both banks of Three Miles Falls Diversion Dam, and fish screens in the West Extension Irrigation District Canal through funding agreements with the Bonneville Power Administration. These became operational in the fall of 1988.

The Bureau of Reclamation and the Oregon Department of Fish and Wildlife also designed and constructed fish ladders and screens at Maxwell Diversion Dam and Canal and at Westland and Stanfield Canal diversions. This work was funded by the Bonneville Power Administration.

Phase I water exchange facilities serve the West Extension Canal and consist of a new canal, pumping plant, and discharge line. The purpose of these facilities is to deliver up to 140 cubic feet per second of Columbia River water for irrigation of West Extension Irrigation District lands, in exchange for Umatilla River flows that are not diverted by the irrigation district at Three Mile Falls Diversion Dam, but left in the lower 3 miles of the Umatilla River.

Columbia River exchange water is diverted at McNary Dam's left fish ladder, conveyed 2 miles by a new concrete-lined canal, and pumped through a 3/4-mile pipeline into the West Extension Canal. These facilities improve Umatilla River flows at critical times of the year for adult fish return and juvenile out-migration. The first water exchange occurred in the 1993 irrigation season. Returning adults were trapped at Three Mile Falls Diversion Dam fish ladder and hauled to higher reaches of the Umatilla River pending completion of Phase II.

Phase II water exchange facilities serve the Hermiston and Stanfield Irrigation Districts. The Hermiston Irrigation District historically diverted water from the Umatilla River in the non-irrigation season, conveyed it through the Feed Canal to Cold Springs Reservoir, and then drew it from the reservoir for summer irrigation. Stanfield Irrigation District historically diverted natural flow and irrigation releases from McKay Reservoir into their Furnish Ditch for direct delivery.

With Phase II, Umatilla River diversions are diminished to leave instream target flows for fish passage. Columbia River exchange water is delivered to Cold Springs Reservoir for the Hermiston Irrigation District and delivered directly into the Stanfield Irrigation District's system.

Phase II includes the following eight major features:

Columbia River Pumping Plant and Discharge Line

The Columbia River Pumping Plant is located on the south shore of the Columbia River just downstream of the Corps of Engineers Sand Station Recreation area about 10 miles northeast of Hermiston, Oregon. The pumping plant lifts water from Lake Wallula, created by McNary Dam, approximately 4,300 feet in a south direction through a 66-inch discharge line into the Columbia-Cold Springs Canal. The maximum pumping rate is 240 cubic feet per second with a total dynamic head of about 321 feet. Average annual pumping is estimated at about 30,000.

Columbia-Cold Springs Canal

The Columbia-Cold Springs Canal begins at the Columbia River Pumping Plant discharge line outlet and extends approximately 23,000 feet in a southwest direction to its terminus near Cold Springs Reservoir. Some 2,000 feet from its terminus, the canal has a turnout to Cold Springs Reservoir. The turnout consists of a gated structure with an overflow weir, a 1,100 foot canal with a measuring flume, a canal to pipe transition structure, and 750 feet of pipeline. The turnout structure and overflow weir provides a wasteway protection for the Columbia-Cold Springs Canal and Cold Springs Pumping Plant. The Columbia-Cold Springs Canal and the Cold Springs Reservoir turnout channel each have a capacity of 240 cubic feet per second.

Cold Springs Reservoir Pumping Plant and Discharge Line

The Cold Springs Reservoir Pumping Plant is located at the terminus of the Columbia-Cold Springs Canal and discharges exchange water into the Stanfield Irrigation District's North Branch Furnish Canal. A 770 foot, 66-inch intake pipe, extends from the Columbia-Cold Springs Canal to the six horizontal centrifugal pumps which lift water through a 60-inch diameter steel discharge line 6200 feet south to a pipe outlet structure in the North Branch Furnish Canal. The pumping plant has a maximum pumping rate of 150 cubic feet per second and a total dynamic head of 60 feet.

North Branch Furnish Canal Enlargement

The original North Branch Furnish Ditch (now renamed the North Branch Furnish Canal) was an unlined earth ditch which historically served about 30 percent of the Stanfield Irrigation District. A 10,000 foot segment of the ditch was redesigned, straightened, enlarged, and concrete-lined to accept higher flows. The North Branch Furnish Canal operates differently than the original ditch. It now has the capability to flow in both directions, the regular flow direction to convey irrigation water from the Umatilla River, and the reverse direction for exchange flow from the Columbia River. The North Branch Furnish Ditch has twenty-one farm turnouts and automated check structures at its north end (N. Check) and south end (Division Point Check).

When the North Branch Furnish Canal is receiving the full 150 cubic feet per second discharge from the Cold Springs Pumping Plant, 38 cubic feet per second flows through the N. Check to serve the tail end of the canal, essentially as it previously did, and the remaining 112 cubic feet per second flows southerly in the restructured canal. The 112 cubic feet per second serves North Branch Furnish Canal turnouts and delivers water to the Division Point Check to serve the Stanfield Branch Furnish Canal.

Stanfield Branch Furnish Canal Enlargement

The original Stanfield Branch Furnish Ditch (renamed the Stanfield Branch Furnish Canal) received water from the Division Point and served about 10 percent of the Stanfield Irrigation District. A 15,700 foot segment of the ditch was realigned, enlarged, and concrete-lined. The enlarged capacity of 97 cubic feet per second meets its original turnout demand of 22 cubic feet per second plus Stanfield relift Pumping Plant demand of 75 cubic feet per second.

Stanfield Relift Pumping Plant

The Stanfield Relift Pumping Plant pumps water from the end of the Stanfield Branch Furnish Canal south into the Main Furnish Ditch. The plant has 4 vertical pumping units with a maximum pumping rate of 75 cubic feet per second and a total dynamic head of 50 feet. The discharge line is a 42-inch diameter high density polyethylene pipeline 8,000 feet long. This supplies water to about 40 percent of the Stanfield Irrigation District and also supplies water for the Echo Pumping Plant.

Additional Features

Additional minor features necessary for the Stanfield Irrigation District water exchange are the 3 cubic feet per second Echo Pumping Plant and an automated monitoring and control system.

Operating Agencies

In the South Division, McKay Reservoir is operated by the Bureau of Reclamation. Stanfield and Westland Irrigation Districts operate their own facilities. The East Division has been operated by the Hermiston Irrigation District since June 23, 1926, and the West Division by the West Extension Irrigation District since April 27, 1926.

Operation of Water Exchange Facilities

The Phase I water exchange facilities are operated by the Bureau of Reclamation. Those Phase II facilities which deliver exchange water to Cold Springs Reservoir and to the North Branch Furnish Canal are operated by the Bureau of Reclamation; the other water exchange facilities which were a part of the original project are operated by the districts.

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In 1903, the Hinkle Ditch Company began irrigating land to the south and east of Hermiston. The point of diversion was about 0.5 mile above Echo and 0.75 mile below the diversion of the present Feed Canal. The company was taken over by the Western Land & Irrigation Company, which considerably enlarged and extended the main canal and laterals. During most years, water could be diverted as desired from the first of March until about the middle of June and occasionally until early in July. During years of short runoff, the last irrigation took place the latter part of May. Lack of water during the summer months greatly hindered development and the Westland Irrigation District was formed to cooperate with the Bureau of Reclamation in utilizing water stored in McKay Reservoir.

In 1905, the Furnish Ditch Company began construction of a system to irrigate 8,000 to 10,000 acres in the vicinity of Stanfield, Oregon. The point of diversion was about 6 miles above that of the present Feed Canal. During 1909, a small reservoir was built on the main stream between Echo and Pendleton to store between 4,000 and 5,000 acre-feet of water. The natural flow of the river usually provided sufficient water for irrigation between the first of March and the middle of June, and the stored supply generally would last until the first of August. Later, the Stanfield Irrigation District was organized to negotiate with the Bureau of Reclamation for storage in McKay Reservoir.


In January 1903, the Reclamation Service began investigations to determine the possibility of irrigating lands on the lower Umatilla River by gravity flow from the Columbia and Snake Rivers. During 1903-1904, the Service surveyed the Umatilla River and its tributaries and mapped the more feasible reservoir sites. Subsequent investigations were made to find a reservoir site on the irrigable lands east of the river. The studies resulted in construction of Cold Springs Reservoir and the establishment of the Umatilla Project. In 1923, construction was started on McKay Dam and Reservoir. The project has been operating since 1927.

In later years, flow design flood studies on McKay Creek indicated that the spillway capacity at McKay Dam would not be adequate under extreme flood conditions. Modifications to increase the spillway capacity were recommended in a report completed in April 1975.

Congress, by the Act of September 6, 1966 (80 Stat. 707, Public Law 89-561) authorized the Secretary of the Interior to conduct a feasibility investigation to expand the irrigation base and to address anadromous fishery needs. A proposed plan which included additional storage facilities was developed, however it was not authorized. Subsequently, through a cooperative local, State, Tribal (Confederated Tribes of the Umatilla Indian Reservation), and Federal effort the Columbia River water exchange plan was developed to help resolve the potential conflict between fishery and irrigation water needs in the Umatilla River basin. A Planning Report-Final Environmental Statement was filed in February 1988.


The East and West Divisions, which originally comprised all the project, were authorized by the Secretary of the Interior on December 4, 1905, under provisions of the original Reclamation Act, section 4, (32 Stat. 388). Recommendations from the Board of Engineers with respect to construction of McKay Dam were approved by the Director of the Reclamation Service (now Bureau of Reclamation) on March 3, 1923. Rehabilitation of Stanfield Irrigation District was accomplished with funds provided by the National Industrial Recovery Act of 1933.

The authorized project purpose of the original project was irrigation.

The Act of March 11, 1976 (90 Stat. 205, Public Law 94-288) reauthorized McKay Dam and Reservoir for the purposes of irrigation, flood control, fish and wildlife, recreation, and safety of dams. This act provided for the modification of the spillway as a safety of dams measure to handle the discharge of large flood inflows. It also reserved 6,000 acre-feet of storage space for exclusive flood control.

Phase I and Phase II water exchange facilities were authorized by the Act of October 28, 1988 (102 Stat. 2791, Public Law 100-557) for the purposes of mitigating losses to anadromous fishery resources and continuing water service to the irrigation districts.


Construction began on the project in 1906, and the first water was available for irrigation from the Cold Springs Reservoir on March 8, 1908. Construction began on McKay Dam in 1923 and was completed in 1927. Rehabilitation of the Stanfield Irrigation District began in 1933 and was completed in 1938.

Construction of the Phase I water exchange facilities began January 1990 and was completed April 1993. Construction of the Phase II water exchange facilities began June 1993 with the Columbia River Pumping Plant and Discharge Line and all of the facilities are completed.

The purpose of Phases I and II are to mitigate losses to anadromous fishery resources and continuing water service to the irrigation districts.

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More than 34,000 acres of land benefit from the irrigation facilities of the project. Principal crops are alfalfa hay and pasture; other crops grown are grain, mint, and vegetables.


Both the McKay and Cold Springs Reservoir areas are national wildlife refuges that are heavily used by migrating waterfowl. The McKay Reservoir area consists of 515 acres of land and 1,200 acres of water surface with 11 miles of shoreline. Some 275 acres of the reservoir area have been designated as public hunting grounds. There are boat launching facilities at the reservoir. Cold Springs Reservoir has 1,530 acres of water surface and 12 miles of shoreline. The reservoir area includes over 1,000 acres of land, of which 900 acres have been designated as public hunting grounds. There are two boat ramps at Cold Springs Reservoir and one at McKay Reservoir. There is also a picnic area at Cold Springs Reservoir.

Flood Control

McKay Dam is operated on an informal basis for flood control and greatly reduces flows that otherwise would be very damaging.

Storage in McKay Reservoir is limited to a maximum of 29,000 acre-feet from the end of the irrigation season until December 1. Thereafter, the reservoir can be filled to specified end-of-month contents with all, but the exclusive flood control space of 6,000 acre-feet, being filled by the end of March. The spillway section modification that increased the capacity from 10,000 to 27,000 cubic feet per second will not prevent damaging flows downstream from the dam during an extreme flood inflow, but it will ensure against a catastrophic flood from dam failure. Releases during an extreme flood inflow would increase gradually, allowing time for warning and evacuation of those people living in the urban developed area between McKay Dam and the Umatilla River.

The McKay Reservoir has 30,000 acre feet of capacity assigned to flood control. The Umatilla Project has provided an accumulated $6,671,000 in flood control benefits from 1950 to 1998.

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Last updated: Jan 03, 2013