Arrowrock Dam
Encyclopedia
Arrowrock Dam is a concrete arch type dam
on the Boise River
, in Idaho
, U.S.A. It opened in 1915 and is located on the border between Boise County
and Elmore County
, upstream of the Lucky Peak Dam
and reservoir. The spillway elevation
for Arrowrock is 3219 feet (981.2 m) above sea level and its primary purpose is to provide irrigation water for agriculture.
began to consider another storage facility further east on the Boise River
. After several surveys, engineers decided upon the Arrowrock site which had previously been the site of a private irrigation venture under the direction of Arthur De Wint Foote
yet failed for lack of funding. The Arrowrock site is at the confluence of the main channel and the south fork. This was to be the most ambitious project to date for Reclamation. At 348 feet (106.1 m), Arrowrock would be the largest concrete
arch dam
in the world. Prior to construction considerable preparatory work would need to be completed. As the structure was some twenty miles (32 km) up the Boise River from the Boise River Diversion Dam
, routing supplies to the worksite would be a massive undertaking unto itself. The Reclamation Service elected to construct a new rail line on the old wagon road leading north to Idaho City. The railroad would begin at the Barberton mill near the Diversion Dam and extend to through a winding canyon up to Arrowrock. Even before the dam had been approved, Reclamation began work on the rail line.
Some significant problems existed with construction of the railroad. The Barberton Lumber Company owned the roads right-of-way. This meant the Reclamation Service needed to come to an agreement over ownership of the rail line. In an unprecedented move, the government agreed to lease the track from Barberton but run the actual locomotive. Part of this agreement stipulated that the line would remain a common carrier. This made the Arrowrock & Boise Railroad the first publicly owned line in the nation. The Service hid this fact from President Howard Taft when they applied for the Arrowrock dam’s approval. Fortunately for Reclamation, Taft failed to recognize the loophole and in June 1910, entire project went forward. Yet when the Oregon Shortline
refused to honor the pact between Barberton and Reclamation, the Arrowrock & Boise terminal was reduced to a field just outside of the Barber lumberyard. On August 22, 1910 the entire deal was finalized and work began on the line to the Arrowrock site.
Salt Lake City’s Manly Brothers won the contract for grading the Arrowrock & Boise road in May, 1911. The government called for force account to lay the track from Barber to the work site. Although the construction was delayed several times by the shortage of railroad ties, workers finished the track in early November. By most accounts, the trip through the canyon was a very long and harrowing event. For the first several months, riders were asked to disembark at the unfinished Gooseneck bridge while the cars were winched across one at a time. Yet once they arrived, most passengers were surprised by what they found. Not only was the view breathtaking but the “work” camp offered amenities that were unavailable to some residents of the Treasure Valley. Not only was the site fully powered, but it also provided a central heating plant, running water and an efficient sewage system. Along with the Reclamation offices, the Arrowrock camp carried a hospital, mess hall, post office, and hotel. Workers and visitors were offered lodging in the site’s hotel, bunkhouses or cottages. In addition to the outdoor recreational activities, the camp also operated a YMCA
., school, and dancehall. At the peak of construction, some 1,400 people had called Arrowrock home, including some 200 families.
To provide power for the site, Reclamation retrofitted The Boise River Diversion Dam with a small powerhouse. Finished in 1912, the plant’s three generators produced 1,500 kilowatts of electricity for Arrowrock’s camp, sawmills, and giant cement mixers. The German made Allis-Chalmers 725 hp turbines were the first in the world to be built with a vertical shaft design. Along with the power lines, government forces hung a two way phone cable to connect Arrowrock with the outside world. In 1976, the power plant was added to the National Register of Historic Places
. After being refurbished by the Bonneville Power Administration
in 2002, it is now on ready reserve status and occasionally provides surplus power during times of peak demand. Special care was made to maintain the historic qualities of the powerhouse. The original governors, slate control panels, transformers, overhead crane, and generator housings, although no longer functional, were retained for historic purposes.
s pulled in anywhere from $3.00 to $4.00. In addition, several deductions were made for room and board. Workers could choose between the dormitory style bunkhouses at $1.25 a month or a private room at $4.00. Seventy-five cents was deducted each day for meals and $1.00 a month went towards hospital’s costs. The work proved moderately dangerous and accounted for numerous injuries and twelve deaths. Yet despite the hazards and reduction in pay, it appears there was a unique level of camaraderie at the Arrowrock site. As stated above, the workers set several construction records, not the least of which included the 527,300 cubic yards of concrete laid on the dam.
The Reclamation Service spared no expense regarding the equipment at Arrowrock Dam. Along with the refurbished 70-ton Atlantic steam shovel from Deer Flat were two versatile 18-ton “dinkey” excavators and several brand new dump cars. The cement mixers produced over 2,000 barrels per day and ran uninterrupted for almost 30 months. Two 12-ton Lidgerwood cableways hovered over the site and moved material and concrete from their loading grounds to the dam site. Scores of horse teams helped carry equipment and gravel from the camp to the various work areas. Additionally, one Buick
and seven Ford trucks serviced both crews and visitors and provided an unexpected level of mobility throughout the campsite. In an effort to alleviate some of the discomfort along the Boise & Arrowrock, Reclamation purchased a 60-ton locomotive and several new passenger cars. For almost five years the train ran faithfully through the canyon, delivering over 89,500 visitors and crewmen. And during its commission, the Boise & Arrowrock traveled more than 110000 miles (177,027.4 km) and carried 14,000,000 tons of freight.
in Switzerland in 1924 with a height of 111.6 meters (366 ft). In addition, engineers pioneered the use of dam instrumentation with the placement of ten thermometers embedded deep within the structure's concrete. Along with innovative contraction joints, the Reclamation Service was able to control the temperature of the setting concrete, ensuring the dams strength. It is 225 feet (68.6 m) thick at the base and fifteen feet thick at the crest. It is serviced by twenty-five outlets some of which are designed to regulate themselves, another first in engineering. Ten outlets were built for an eventual power plant, but they have yet to be utilized. In total, the dam contains 585,160 cubic yards of concrete and the reservoir holds over 286000 acre.ft of irrigation water. Within the first week of operation, an estimated 12,000 visitors braved the canyon ride to see the dam. Yet as interest waned, the Arrowrock & Boise Railroad schedule dropped significantly. The campsite, once a bustling hive of activity, was quickly becoming a ghost town
. And on August 11, 1916, the government decommissioned its very first public carrier.
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...
on the Boise River
Boise River
The Boise River is a tributary of the Snake River in the northwestern United States. It drains a rugged portion of the Sawtooth Range in southwestern Idaho northeast of Boise, as well as part of the western Snake River Plain...
, in Idaho
Idaho
Idaho is a state in the Rocky Mountain area of the United States. The state's largest city and capital is Boise. Residents are called "Idahoans". Idaho was admitted to the Union on July 3, 1890, as the 43rd state....
, U.S.A. It opened in 1915 and is located on the border between Boise County
Boise County, Idaho
Boise County is a rural mountain county in the U.S. state of Idaho. The population was 6,670 at the 2000 census; it was estimated at 7,571 in 2007...
and Elmore County
Elmore County, Idaho
Elmore County is a county located in the U.S. state of Idaho. As of the 2010 Census the county had a population of 27,038, down 7.2% from 29,130 in 2000. The largest city and county seat is Mountain Home....
, upstream of the Lucky Peak Dam
Lucky Peak Dam
Lucky Peak Dam is a rolled earth and gravel fill dam on the Boise River in Ada County, Idaho, U.S.A.. It is directly downstream of Arrowrock Dam, a concrete arch structure completed in 1915. At the time of its construction in the early 1950s, Lucky Peak's primary purpose was flood control, with a...
and reservoir. The spillway elevation
Elevation
The elevation of a geographic location is its height above a fixed reference point, most commonly a reference geoid, a mathematical model of the Earth's sea level as an equipotential gravitational surface ....
for Arrowrock is 3219 feet (981.2 m) above sea level and its primary purpose is to provide irrigation water for agriculture.
Preparations
In 1910 the Reclamation ServiceUnited States Bureau of Reclamation
The United States Bureau of Reclamation , and formerly the United States Reclamation Service , is an agency under the U.S...
began to consider another storage facility further east on the Boise River
Boise River
The Boise River is a tributary of the Snake River in the northwestern United States. It drains a rugged portion of the Sawtooth Range in southwestern Idaho northeast of Boise, as well as part of the western Snake River Plain...
. After several surveys, engineers decided upon the Arrowrock site which had previously been the site of a private irrigation venture under the direction of Arthur De Wint Foote
Arthur De Wint Foote
Arthur De Wint Foote was a mining and civil engineer who built Foote's Crossing across the Middle Yuba River and Foote's Crossing Road , and designed the hydraulic wheel for the North Star Mine Powerhouse, now a California Historical Landmark.-Early years:Foote was born...
yet failed for lack of funding. The Arrowrock site is at the confluence of the main channel and the south fork. This was to be the most ambitious project to date for Reclamation. At 348 feet (106.1 m), Arrowrock would be the largest concrete
Concrete
Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...
arch dam
Arch dam
An arch dam is a type of dam that is curved and commonly built with concrete. The arch dam is a structure that is designed to curve upstream so that the force of the water against it, known as hydrostatic pressure, presses against the arch, compressing and strengthening the structure as it pushes...
in the world. Prior to construction considerable preparatory work would need to be completed. As the structure was some twenty miles (32 km) up the Boise River from the Boise River Diversion Dam
Boise River Diversion Dam
The Boise River Diversion Dam is a diversion dam on the Boise River in Idaho.In March, 1906 the Utah Fire Proofing Company began work on the Boise River Diversion Dam with the provision that the structure would be completed within one year. It soon became apparent that the dam would not be finished...
, routing supplies to the worksite would be a massive undertaking unto itself. The Reclamation Service elected to construct a new rail line on the old wagon road leading north to Idaho City. The railroad would begin at the Barberton mill near the Diversion Dam and extend to through a winding canyon up to Arrowrock. Even before the dam had been approved, Reclamation began work on the rail line.
Some significant problems existed with construction of the railroad. The Barberton Lumber Company owned the roads right-of-way. This meant the Reclamation Service needed to come to an agreement over ownership of the rail line. In an unprecedented move, the government agreed to lease the track from Barberton but run the actual locomotive. Part of this agreement stipulated that the line would remain a common carrier. This made the Arrowrock & Boise Railroad the first publicly owned line in the nation. The Service hid this fact from President Howard Taft when they applied for the Arrowrock dam’s approval. Fortunately for Reclamation, Taft failed to recognize the loophole and in June 1910, entire project went forward. Yet when the Oregon Shortline
Oregon Short Line Railroad
The Oregon Short Line Railroad was a railroad in the U.S. states of Wyoming, Idaho, Utah, Montana and Oregon. The line was as organized the Oregon Short Line Railway in 1881 as a subsidiary of Union Pacific Railway. Union Pacific intended the line to be the shortest route from Wyoming to Oregon...
refused to honor the pact between Barberton and Reclamation, the Arrowrock & Boise terminal was reduced to a field just outside of the Barber lumberyard. On August 22, 1910 the entire deal was finalized and work began on the line to the Arrowrock site.
Salt Lake City’s Manly Brothers won the contract for grading the Arrowrock & Boise road in May, 1911. The government called for force account to lay the track from Barber to the work site. Although the construction was delayed several times by the shortage of railroad ties, workers finished the track in early November. By most accounts, the trip through the canyon was a very long and harrowing event. For the first several months, riders were asked to disembark at the unfinished Gooseneck bridge while the cars were winched across one at a time. Yet once they arrived, most passengers were surprised by what they found. Not only was the view breathtaking but the “work” camp offered amenities that were unavailable to some residents of the Treasure Valley. Not only was the site fully powered, but it also provided a central heating plant, running water and an efficient sewage system. Along with the Reclamation offices, the Arrowrock camp carried a hospital, mess hall, post office, and hotel. Workers and visitors were offered lodging in the site’s hotel, bunkhouses or cottages. In addition to the outdoor recreational activities, the camp also operated a YMCA
YMCA
The Young Men's Christian Association is a worldwide organization of more than 45 million members from 125 national federations affiliated through the World Alliance of YMCAs...
., school, and dancehall. At the peak of construction, some 1,400 people had called Arrowrock home, including some 200 families.
To provide power for the site, Reclamation retrofitted The Boise River Diversion Dam with a small powerhouse. Finished in 1912, the plant’s three generators produced 1,500 kilowatts of electricity for Arrowrock’s camp, sawmills, and giant cement mixers. The German made Allis-Chalmers 725 hp turbines were the first in the world to be built with a vertical shaft design. Along with the power lines, government forces hung a two way phone cable to connect Arrowrock with the outside world. In 1976, the power plant was added to the National Register of Historic Places
National Register of Historic Places
The National Register of Historic Places is the United States government's official list of districts, sites, buildings, structures, and objects deemed worthy of preservation...
. After being refurbished by the Bonneville Power Administration
Bonneville Power Administration
The Bonneville Power Administration is an American federal agency based in the Pacific Northwest. BPA was created by an act of Congress in 1937 to market electric power from the Bonneville Dam located on the Columbia River and to construct facilities necessary to transmit that power...
in 2002, it is now on ready reserve status and occasionally provides surplus power during times of peak demand. Special care was made to maintain the historic qualities of the powerhouse. The original governors, slate control panels, transformers, overhead crane, and generator housings, although no longer functional, were retained for historic purposes.
Work Begins
Work began on the Arrowrock Dam in early 1912 and moved along at a record-setting pace. As labor was becoming more plentiful with the completion of Deer Flat and the Diversion Dam, wage rates began to decrease. Common laborers were now offered $2.40 and day while skilled workerSkilled worker
A skilled worker is any worker who has some special skill, knowledge, or ability in their work. A skilled worker may have attended a college, university or technical school. Or, a skilled worker may have learned their skills on the job...
s pulled in anywhere from $3.00 to $4.00. In addition, several deductions were made for room and board. Workers could choose between the dormitory style bunkhouses at $1.25 a month or a private room at $4.00. Seventy-five cents was deducted each day for meals and $1.00 a month went towards hospital’s costs. The work proved moderately dangerous and accounted for numerous injuries and twelve deaths. Yet despite the hazards and reduction in pay, it appears there was a unique level of camaraderie at the Arrowrock site. As stated above, the workers set several construction records, not the least of which included the 527,300 cubic yards of concrete laid on the dam.
The Reclamation Service spared no expense regarding the equipment at Arrowrock Dam. Along with the refurbished 70-ton Atlantic steam shovel from Deer Flat were two versatile 18-ton “dinkey” excavators and several brand new dump cars. The cement mixers produced over 2,000 barrels per day and ran uninterrupted for almost 30 months. Two 12-ton Lidgerwood cableways hovered over the site and moved material and concrete from their loading grounds to the dam site. Scores of horse teams helped carry equipment and gravel from the camp to the various work areas. Additionally, one Buick
Buick
Buick is a premium brand of General Motors . Buick models are sold in the United States, Canada, Mexico, China, Taiwan, and Israel, with China being its largest market. Buick holds the distinction as the oldest active American make...
and seven Ford trucks serviced both crews and visitors and provided an unexpected level of mobility throughout the campsite. In an effort to alleviate some of the discomfort along the Boise & Arrowrock, Reclamation purchased a 60-ton locomotive and several new passenger cars. For almost five years the train ran faithfully through the canyon, delivering over 89,500 visitors and crewmen. And during its commission, the Boise & Arrowrock traveled more than 110000 miles (177,027.4 km) and carried 14,000,000 tons of freight.
Dedication
On October 4, 1915 the Arrowrock Dam was finally dedicated. As stated above, it was the tallest dam in the world, a claim it would hold until completion of the Schräh damWägitalersee
Wägitalersee is an artificial lake in Wägital, a valley in the canton of Schwyz, Switzerland. The lake is surrounded by the mountains Gross Aubrig, Fluebrig, Zindlenspitz, Brünnelistock and Bockmattli. The reservoir is located in the municipalitiy of Innerthal....
in Switzerland in 1924 with a height of 111.6 meters (366 ft). In addition, engineers pioneered the use of dam instrumentation with the placement of ten thermometers embedded deep within the structure's concrete. Along with innovative contraction joints, the Reclamation Service was able to control the temperature of the setting concrete, ensuring the dams strength. It is 225 feet (68.6 m) thick at the base and fifteen feet thick at the crest. It is serviced by twenty-five outlets some of which are designed to regulate themselves, another first in engineering. Ten outlets were built for an eventual power plant, but they have yet to be utilized. In total, the dam contains 585,160 cubic yards of concrete and the reservoir holds over 286000 acre.ft of irrigation water. Within the first week of operation, an estimated 12,000 visitors braved the canyon ride to see the dam. Yet as interest waned, the Arrowrock & Boise Railroad schedule dropped significantly. The campsite, once a bustling hive of activity, was quickly becoming a ghost town
Ghost town
A ghost town is an abandoned town or city. A town often becomes a ghost town because the economic activity that supported it has failed, or due to natural or human-caused disasters such as floods, government actions, uncontrolled lawlessness, war, or nuclear disasters...
. And on August 11, 1916, the government decommissioned its very first public carrier.
External links
- U.S. Bureau of Reclamation - Arrowrock Dam
- Idaho Dept. of Water resources - photo - Arrowrock Dam