The Columbia Basin Project (CBP) is the nation's second-largest U.S. Bureau of Reclamation irrigation project. At 670,000 acres under irrigation as of 2021, the project is still unfinished, as more than 1,095,000 acres are eligible to receive water in the project area, which covers parts of Adams, Douglas, Franklin, Lincoln, Grant, and Walla Walla counties in Eastern Washington. A multipurpose irrigation, power, and flood-control project, the CBP had many firsts in its design and construction, which began in 1945. Prior to the CBP, the 12,700-square-mile Columbia Plateau, also known as the Columbia Basin, was sparsely populated, had very little farming development, and was a "great expanse of sagebrush land extending as far as the eye can see" (Condensed Fact Sheet, 1952). The CBP transformed the plateau into one of the most productive agricultural areas in Washington.
A Vast Expanse
The Columbia Plateau is located in Central Washington, east of the Columbia River in an area that was carved out by the ancient Missoula Floods into the channeled scablands. The expanse of the Columbia Plateau was originally inhabited by Native American tribes consisting of the Colville, Lakes, Sanpoil, Nespelem, Okanogan, Chelan, Methow, Wenatchi, Entiat, Moses-Columbia, Palus, and Chief Joseph's Band of Nez Perce, along with the other tribes/bands which today are part of the Wanapum Band, Confederated Tribes of the Yakama Nation, and the Confederated Tribes of the Umatilla Reservation. As a hunter-gatherer culture these tribes/bands moved throughout the lands of the Columbia Basin in season. Some, such as Chief Moses, became identified with features of the land, such as Moses Lake, his namesake.
Railroads led development of the Columbia Basin. In 1881, the Northern Pacific Railroad first crossed the eastern side of the Columbia Basin, establishing foundations for the towns of Eltopia, Connell, and Pasco with its transcontinental line. In 1890, the Northern Pacific built across the northern part of the plateau to reach Coulee City. In 1892, the Great Northern Railway cut farther into the Columbia Basin with its transcontinental mainline as it headed west to Wenatchee, establishing Ephrata, Quincy, and Stratford. Later, when the Chicago, Milwaukee, Saint Paul and Pacific Railroad built its Pacific Extension from the Midwest to Tacoma, it established the towns of Othello, Warden, and Beverly, and built branch lines including one to Neppel along Moses Lake in 1912. But while there were three transcontinental railroads crossing the Columbia Basin, it would take more than pamphlets, promotion, and land division to give farmers the ability to turn this desert into a Garden of Eden, for what was needed was water.
Early Irrigation Schemes
Early settlers had to bring water by barrel or bucket if they lacked a lake source to pump water from. Some of the land was so dry, even dry land farming was not sustainable, and it was apparent that large-scale gravity irrigation was needed if the Columbia Basin were to be developed. Irrigation schemes abounded starting in 1892 and continuing through 1912, but all of them failed without turning a shovel of dirt, except for the Stratford Irrigation Company. With a pump and an irrigation system, it was able to irrigate 1,200 acres with water. This irrigation project and other smaller ones, including those around Moses Lake, relied on pumping water from lakes or wells. This became prohibitively expensive, as the apple orchards and other irrigated crops had low returns even before the Great Depression.
In 1902, the U.S. Reclamation Service investigated the area for possible irrigation development, and along with the State of Washington and the Northern Pacific Railway proceeded to study it from 1903-1907 with hopes of bringing water from the Palouse River, or pumping from the Columbia River, to the lands in the southern part of the Columbia Basin. By 1913, the Reclamation Service had concluded that it was not feasible; the plan was simply too expensive.
It was not until June 18, 1918, when Rufus Woods published William "Billy" Clapp's plan to irrigate the Columbia Basin by building a dam on the Columbia River that would bring water through the Grand Coulee -- an ancient, cliff-walled riverbed in North Central Washington -- that a potential federal irrigation project was debated again. This scheme was promoted, lobbied, and fought over by residents of Eastern Washington and championed by a group of four: Clapp, James O'Sullivan, Gale Mathews and Rufus Woods. It was studied by the Army Corps of Engineers and surveyed by Reclamation, until finally $377,000 was allocated in 1933 from the National Industrial Recovery Act for preliminary work at the site of Grand Coulee Dam.
Grand Coulee Dam
It would take a gargantuan concrete gravity dam to back up the Columbia River and bring water to the Columbia Basin. Grand Coulee Dam impounded the river to generate power and created a giant reservoir, Franklin Delano Roosevelt Lake, to irrigate the Columbia Plateau. Grand Coulee Dam and its two powerhouses were built from 1933-1951. A third powerhouse was added in 1967-1975. Construction on the irrigation elements of the Columbia Basin Project began in 1945, shortly after the end of World War II.
To reach all of the irrigable acreage in the Columbia Basin, water is pumped up from behind Grand Coulee Dam through the John Keys III Pump-Generating Plant (originally called the Grand Coulee Pumping Plant), after which it travels down the Feeder Canal to the North Dam and then empties out into the Grand Coulee to be impounded behind Dry Falls Dam (originally called South Coulee Dam) in Banks Lake. Banks Lake is an equalizing reservoir that stretches for 27 miles in the Grand Coulee, 500 feet above the Columbia. The water then makes its way down through the system via the Main Canal, branching off into a series of main canals (West, East Low, Potholes) and lateral canals (Royal Branch, Wahluke Branch, Eltopia Branch) which irrigate the entire region.
This system consists of 333 miles of main canals, approximately 2,000 miles of laterals, and 3,500 miles of drains and wasteways. Irrigated lands of the CBP range from over 1,500 feet above sea level at the northern end to 400 feet above sea level at the southern end, where the Snake and Columbia rivers join. This topography makes a gravity irrigation system possible. The CBP was so huge that three local irrigation districts were formed to repay Reclamation for the cost of building the CBP and would eventually take over operation and maintenance of the project under contract. They were the Quincy-Columbia Basin Irrigation District, East Columbia Basin Irrigation District, and the South Columbia Basin Irrigation District.
During the late nineteenth century and into the twentieth century, there was a flurry of development and founding of towns across the Columbia Basin. However, by the time Great Depression was over, the few towns that barely survived were never fully developed, and additional housing would be needed for the thousands of workers who now came to the area to help build the irrigation division. Construction camps were built to house the workers who built the canals, tunnels, siphons and dams. Some locations had construction camps built by Reclamation with World War II government surplus Quonset Huts and Hutmets, along with a bevy of Transa-Home Trailers. Two hundred Quonset Huts from U.S. Army bases in Ephrata and Pasco were moved by truck and reassembled at various locations. By 1947, Reclamation had bought several hundred wooden Hutments from the U.S. Army's Ephrata Air Base and they were re-used, rebuilt, or modified all over the CBP into residences at sites such as the Pasco Development Farm, Pasco Pumping Plant, Potholes Dam, and Wilson Creek. Some Hutments were remade into bathhouses or garages. At Quincy, a carpenter shop was built from them.
Some of those Reclamation construction camps were later developed into 12 Watermaster Headquarters located throughout the CBP. The Watermaster sites, built in the 1950s, included offices, shops, and more substantial housing for the workers. Ephrata was the headquarters for the irrigation division, with the 12 sub-headquarters spaced 15-20 miles apart to control individual sections of the system. CBP Watermaster Headquarters are: Adco, Winchester, Quincy, George, Blythe, Royal Camp, Wahluke, Moses Lake, Warden, Othello, Mesa, and Eltopia.
Construction Begins: Pumping Plant at Grand Coulee Dam
Construction on the CBP irrigation plan began in 1945, starting at the source of the project with the construction of an immense pumping plant to push water up from the reservoir behind Grand Coulee Dam through 12 discharge pipes into the Grand Coulee.
This pumping plant contained six pumps with motors that were completed in stages from 1951 to 1953. On June 14, 1951, the first water was pumped from the pumping plant into the Feeder Canal to fill the reservoirs behind North and Dry Falls dams. This celebrated event began with the Secretary of the Interior pushing the start button of the first pump from Washington D.C. while simultaneously young women poured water from each state and territory of the Union into the Feeder Canal at a public gathering. From 1971-1984 six generating pumps were added to the pumping plant. Unlike the original 1950s pumps, these six pump generating units could be used in reverse to generate power when not needed for pumping.
Feeder Canal and North Dam
Water from the pumping plant is discharged into the 1.6-mile-long Feeder Canal, which delivers water into North Dam. The Feeder Canal is 50 feet wide at the bottom and 25 feet deep. The control structure discharge chute is controlled by three, 24-by-25-feet radial gates in the abutment of the North Dam. These gates are unique in that they are designed to resist pressure not only from the upstream, but also the downstream side. North Dam is located at the northern end of the Grand Coulee. It is 145 feet high and 1,450 feet long with 1,473,000 cubic yards of material used to construct it. These structures were built from 1946-1951.
Dry Falls Dam
Located at the southern end of the Grand Coulee is Dry Falls Dam. This 9,800-feet-long, rock-faced earth-fill dam was constructed from 1946-1949 to impound water from Banks Lake and to regulate flow into the Main Canal for the CBP. The dam was constructed by the contractor team of Roy L. Blair & Company and James Crick & Sons of Spokane, whose contract also called for the construction of the Main Canal from Station 2+29 to 24+00. To house the construction workers, the contractors built a construction camp near Coulee City that included a restaurant open 24 hours a day.
Starting in the fall of 1946, rock excavations cleared the site down to bedrock and built a 30-foot-wide cutoff trench in bedrock along the entire length of the dam. A continuous concrete cutoff wall was built under the dam inside the cutoff trench to prevent seepage of water. Dry Falls Dam was designed as a zoned earth embankment structure with a narrow impervious central core, a semi-pervious layer on either side of the core, and a layer of rock fill over the semi-pervious layer. Horizontal layers were broken out into three zones totaling 1,630,399 cubic yards. The headworks was started in March 1948 and completed by June 1949. The headworks also serve as the reservoir outlet, as there is no spillway. As much as 13,200 cubic feet per second of water pass out of the Dry Falls Headworks into the Main Canal.
The Main Canal starts at the Dry Falls Dam outlet gates adjacent to Coulee City. This approximately 21-mile-long complex structure consists of the 1,038-foot-long Bacon Siphon, 10,045-foot-long Bacon Tunnel, Pinto Dam, 5.9 miles of canal, and a bifurcation structure near Adco where the canal ends and the West and East Low Canals begin.
Besides engineered works in concrete, it also uses Trail Lake and Billy Clapp Lake (originally called Long Lake) to move water like a canal through the system. The Main Canal recreated a 165-foot-tall ancient waterfall called Summer Falls into the upper end of Billy Clapp Lake. The Main Canal system was constructed from 1946-1951. As the Main Canal exits the Long Lake Dam Headworks, at Pinto Dam it becomes a colossal concrete-lined canal. This section of canal -- 125 feet across, 25 feet deep, and 50 feet wide at the bottom -- was the world's largest when it was completed in 1951. From 1976-1980 the Main Canal was enlarged from Dry Falls Dam to Bacon Siphon. The twin Bacon Siphon and Bacon Tunnel were then built to increase the water capacity of the system.
Within the Main Canal system is Pinto Dam (originally called Long Lake Dam), approximately 2.5 miles from Stratford. Pinto Dam is at the southern end of Long Lake Coulee, a wide, deep channel cut in the basalt flows during the Pleistocene Period and surrounded by Pinto Ridge. Pinto Dam was designed as a zoned earth embankment structure with a narrow impervious central core that was built by J. A. Terteling & Sons, Inc. In February 1947, the contractor had completed a construction camp near the dam to house workers with an additional 32 hutments at Wilson Creek for workers with families. The 1,900-foot-long, 130-foot-high rock-faced zoned earth fill dam was constructed from 1946 to 1948. It enabled Reclamation to avoid "construction of an equal length of very difficult and expensive canal" (U.S. Department of the Interior, 1965, 2) by flooding Pot, Coffee Pot, and Long Lakes and making this stretch of canal into one 5.5-mile-long Billy Clapp Lake.
The CBP Main Canal returns to a trapezoidal canal at the Long Lake Dam Headworks. The headworks were built from 1949-1950 after Pinto Dam was completed, and unlike Dry Falls Dam these headworks are not the dam's outlet works. These headworks on the west side of the coulee have three of the largest radial gates (25-by-25 feet) used on the Main Canal system for regulation of water into the canal.
The 88-mile-long West Canal starts at the bifurcation works where the Main Canal splits, running west for 2.5 miles, then southwest to Quincy and then south along its route to irrigate the western part of the CBP. This western main canal was built from 1946-1955 with construction done in five consecutive sections.
While it is like many other Reclamation canals in its construction, its size separates it from the others. At its largest, it is 95 feet wide at the top and 38 feet wide at the bottom. In order to carry 5,100 cubic feet per second along its route, the canal uses several large engineered structures, such as the 9,150-foot-long Frenchman Hills Tunnel, and siphons such as the Soap Lake Siphon, which is one of the longest in the world at 12,820 feet. The West Canal also delivers water to two large laterals: the 23.39-mile-long W20 Lateral and the 8.5-mile-long Royal Branch Canal, as well as numerous smaller laterals throughout its route. Water from this western section of the CBP drains via Winchester and Frenchman Hills wasteways into Potholes Reservoir.
East Low Canal
The 87-mile-long East Low Canal starts at the bifurcation works where the Main Canal splits, running south-southeast along its route to irrigate the eastern part of the CBP. The canal terminates east of Othello. It was originally to have an additional 30 miles, ending south of Eltopia, but like the East High Canal, this extending of the East Low Canal ended up being indefinitely deferred and not constructed. This eastern main canal was built from 1946-1954 with construction done in three consecutive sections. Like with West Canal the East Low Canal's size distinguishes it from the other canals built during this time for its earthen-lined sections are 68 feet wide at the bottom and 15.5 feet deep, while the concrete-lined portions are 20 feet wide at the bottom and 19 feet deep. In order to carry 4,500 cubic feet per second along its route, the canal uses several large engineered structures, such as the 3,330-foot-long Crab Creek Siphon No. 1, the 1,440-foot-long Crab Creek Siphon No. 2, and the 1,800-foot-long Broken Rock Siphon.
In order to continually use this precious resource of water, Reclamation devised a dam 15 miles south of Moses Lake to capture the return flows off irrigated lands and reuse the water to irrigate lands in the southeast portion of the project.
O'Sullivan Dam (originally called Potholes Dam) is an enormous 19,000-foot-long, 200-foot-high rock-faced zoned earth fill dam. It was built from 1947 to 1949 on Crab Creek at the east end of the Frenchman Hills by not one, but three construction firms under one contract: the C. F. Lytle Company, Green Construction Company, and Amis Construction Company. When completed it was the fourth-longest dam in the world, containing 9,190,000 yards of material. This dam created Potholes Reservoir, which also can be fed by the West and East Low canals if needed via the Winchester and Rocky Coulee wasteways.
Construction of O'Sullivan Dam required two construction camps for housing workers, warehouses, and testing laboratories. Lytle-Amis-Green built their camp out of 155 surplus Hutmets from the Ephrata air base. Life in the camp was sometimes unpleasant, as in 1947 Reclamation reported that many people were sickened in the Amick Cafeteria from soapy dishes that had not been cleaned properly. Reclamation's construction camp at Potholes Dam had an office, garage, recreation building, warehouses, a soils laboratory, a well with a 42,000-gallon water tower, residences, and Hutmets that were made into garages. A total of 47 Quonset Huts were used at this location for the various buildings and residences. These large camps at Potholes Dam were not just home to single men, but many families -- there were 131 children from both camps who were bused to schools in Moses Lake.
The last major impoundment on the CBP system is the Scooteney Dike (originally called the North Scooteney Dike) southeast of Othello. Like the Potholes Dam, this 3,700-foot-long, 16-foot-tall earthen dike impounds the water from return flows and the East Low Canal via the Scooteney Wasteway for one final delivery by the Potholes Canal (orginally called the Potholes East Canal) to the lands around Pasco. This dike was built by J. A. Terteling & Sons in 1950. The headworks consist of a concrete structure with a 20-by-10-feet radial gate to control flows into the Potholes Canal.
The Potholes Canal extends southward from O'Sullivan Dam and slowly west to irrigate the southern portion of the CBP before exiting into the Columbia River at Pasco. It was built from 1949-1955 with construction done in four sections. It is 62.4 miles long with "about eight miles of lake, reservoir, and natural channel utilized for conducting canal water" totaling about 70 miles in length for the system (U.S. Department of the Interior, 1958, detail page). The Potholes Canal can provide water to irrigate 278,816 acres.
Completion of this system enabled water from the Columbia River to travel the entire distance from Lake Roosevelt to just north of Pasco via canals of the CBP. While it is like many other 1940s-1950s Reclamation canals in its construction, its size distinguishes it from other main canals. There were 10 checks structures, two chutes, two drops, and two wasteways built along the canal with a bottom width of 14 to 84 feet to carry a maximum 3,900 cubic feet per second. The system runs through two reservoirs, Soda Lake and Scooteney, which were created by Soda Lake Dike (1,680 feet long) and Scooteney Dike, respectively. The Potholes East Canal also delivers water to two large laterals: the 49-mile-long Wahluke Branch Canal and the 25-mile-long Eltopia Branch Canal, plus numerous smaller laterals throughout its route.
Pumping in Pasco
Where gravity could not reach the desert to transform it, Reclamation built 240 pumping plants, ranging in size from small 3 cubic feet per second, outdoor pumps on sublaterals to monumental indoor pumping plants such as the 176.6-foot-long, nine-pump Frenchman Hills Pumping Plant. A majority of the largest pumping plants are located on the western portion of the CBP, where the land has more hills with evocative names such as Evergreen, Low Gap, Babcock, Hope Valley, and Sand Hollow.
Ironically, the first land irrigated by the CBP was not by gravity, but by a pumping plant northwest of Pasco that pumped water from the Columbia River to the Pasco Pump Unit. It was started in 1946 and by May 15, 1948 water was delivered to the farms. The 27.25 mile long Pasco Pump Lateral system was also an experiment in new canal construction with asphalt, not concrete, being used to line a majority of the earthen Main Canal in this sandy and porous section of land. All of Reclamation's projects involved new machinery to build these complex irrigation systems, and so the Pasco Pump Unit was the first extensive test of the Ekenstam asphalt lining machine to pave the Main Canal with asphalt. The lateral canals of the system were lined with concrete, but placement of it was also an experiment using pneumatically applied mortar (also called gunite) over the traditional poured-in-place panels.
The system was completed with pipelines, earthen drainage ditches and six relift pumping plant to bring the water to higher elevations in the Pasco Pump Unit system. Settlers were lured to the CBP with photographs of the bounty that came from Irrigation Block No. 1. By 1955, the Potholes East Canal reached this location and water was now diverted via gravity to the Pasco Pump Lateral. The pump house along the Columbia was mothballed, its discharge line and its gigantic pumps were disassembled, and the pumps were moved to be reused in the Frenchman Hills Pumping Plant.
First Water, and a Celebration
After the reservoir behind Dry Falls Dam had filled and enough of the West and East canal systems had been completed to start opening up some farm units, water was turned on for the first time in 1952. From May 22 to June 1, 1952 communities throughout the project area from Coulee City to Pasco hosted parades, celebrations, and even an Aqua Rama to commemorate the moment. Ephrata, as the unofficial capital of the CBP, hosted a Little World's Fair at the former Ephrata Air Base.
On May 29 at midnight near Moses Lake, a vast number of volunteers assembled to build a complete farm for a new owner chosen by the Veteran of Foreign Wars. Donald D. Dunn's 80-acre farm ground was cleared, planted with potatoes, beans, and alfalfa, while his new house, shop, and other necessary outbuildings were constructed in a single day. Everything was free, including the farm equipment.
End of Major Construction
Even with the first delivery of water in 1952 through the gravity system, construction continued until 1959. On July 29, 1959 landowners in the East Columbia Basin Irrigation District voted down an amended repayment contract between the three irrigation districts within the CBP, which "mothballed" construction of the project "so that the cost of construction of irrigation features would not exceed the monetary limits set forth in the 1945 repayment contract" (U.S. Department of the Interior, 1959, 1). With this the number of Reclamation employees was reduced from 1,307 to 925, and the development of the lateral system in the existing canals continued on for the next several decades until Reclamation turned over operation and maintenance of the CBP via contract to the three irrigation districts in 1968.
The Columbia Basin Act of 1943
In conjunction with the CBP, Reclamation came up with a revolutionary way federal land could be divided up for new owners. Prior to the CBP Reclamation farm units were normally set in the 40- to 80-acre range no matter how rich or poor the land was. In the 1930s Reclamation envisioned the CBP as a new home for Dust Bowl refugees, but World War II delayed construction of the irrigation division. Nonetheless, in 1943 the Columbia Basin Project Act was passed through Congress, allowing for the "size of the farm unit to be based on the quality of the soil, the topography of the lands, and the tracts relationship to the irrigation system" rather than a set amount (Simonds, 67). So, farm tracts were drawn up large enough to provide what Reclamation planners thought would attain a comfortable living for the farmers. War veterans were given a preference in obtaining land. Reclamation built development farms near Pasco, Moses Lake, Winchester, Burke (George area today), and Othello to show what the irrigated land could produce, and tested different types of crops to show which ones could succeed in the soil.
However, when the new policies were implemented after World War II, what had been a good idea in the 1930s -- small farms growing row crops -- was quickly determined to be inefficient as agriculture in the post-war era became more mechanized with fewer laborers and larger farms using center-pivot sprinklers. Reclamation had anticipated 10,000 to 15,000 farms, but there never were enough small farmers to reach the levels anticipated to get land development funds from Congress. While 160 acres were allowed under the Columbia Basin Project Act, a majority of the lands were 60 to 120 acres, with some, such as Donald Dunn's land, being only 80 acres. By 1962, the provisions of the Columbia Basin Project Act relating to the size of farms were abandoned in favor of a standard 160 acres per individual farmer or 320 acres for a husband and wife. By 1965 the average size of farms in the project area was just over 203 acres, and by 1967 there were 5,463 individual farms on the CBP. Farms continued to grow, to an average of 268 acres in 1992, but with only 2,050 farm units.
Originally, the CBP would have been 2 million acres when planned in the 1930s, but when it came time to start developing the irrigation system, it became apparent that certain lands were not irrigable or feasible. On the eastern portion of the project, 300,000 acres were petitioned out of the project. Wheat farmers on the easternmost side of the Columbia Plateau did not really need irrigation, nor did they want to limit the size of the land they owned or take on more debt. Furthermore, they were enjoying a wet cycle that began in 1940 and were buoyed by higher yields and prices before and after World War II. So as early as 1946 they started to pull out of the projected 1,095,000-acre project and voted down a proposed East High Canal, a project that was determined to be impractical before it was even designed.
By the 1970s these farmers did need irrigation, but it was too late. Reclamation was not going to re-start construction. Farmers in the area found relief in being able to tap the Odessa Subarea, but today this aquifer is declining to such an extent that it is at risk of disappearing.
Note: This article is part of Cultivating Washington, The History of Our State’s Food, Land, and People, which includes more agriculture-related content, videos, and curriculum.