Glen Canyon Dam - Construction - Site Preparations

Site Preparations

Glen Canyon's design was overall based on that of Hoover Dam, a massive concrete arch-gravity structure anchored in solid bedrock, with several changes. The engineers wanted the dam to rely predominantly on its arch shape to carry the tremendous pressure of the impounded water into the canyon walls instead of depending on the sheer weight of the structure to hold the reservoir back, as had been done at Hoover. However, most of the rock in the region consists of porous and relatively weak Navajo sandstone in contrast to the stronger rock at the Hoover Dam site, forcing the Glen Canyon design to follow more conservative lines by greatly thickening the abutments, thus increasing the surface area through which the weight of dam and reservoir would be transmitted to the rock and relieving the pressure per square inch on the highly breakable cliffs. The primary designer and overseer of construction was veteran Reclamation engineer Lem F. Wylie, who had worked on the Hoover Dam project and had been chief engineer of six other USBR dams.

Before building the dam, Reclamation identified two possible sites, both located in the narrow lower reaches of Glen Canyon shortly upstream of Lee's Ferry. One, just 4 miles (6.4 km) upstream, was originally considered the superior site, but the final decision was to build the dam 16.5 miles (26.6 km) upstream because of stronger rock and easier access to the gravel mining area at the confluence of Wahweap Creek with the Colorado. The dam site lay in a remote, rugged area of the Colorado Plateau, more than 30 miles (48 km) from the closest paved road, U.S. Highway 89, and a whole new road had to be constructed, branching off from Highway 89 north of Flagstaff, Arizona, and running through the dam site to its terminus at Kanab, Utah. Because of the isolated location, acquiring the land at the dam and reservoir sites was not incredibly difficult, but still conflicts arose with the ranchers and miners in the area (many of the Navajo tribe). Much of the land acquired for the dam was through an exchange with the Navajo, in which the tribe ceded Manson Mesa south of the dam site for a similar-sized chunk of land in New Mexico, which the Navajo had long coveted.

As a road link was obviously needed for transport across the canyon from one end of the dam site to the other, a bridge had to be built, several hundred feet downstream of the dam and capable of carrying not only workers but heavy construction material. An earlier footbridge built of chicken wire and metal grates certainly did not fit the bill. The contract for building the bridge was awarded to Peter Kiewit Sons and the Judson Pacific Murphy Co. for $4 million and construction began in late 1956, reaching completion on August 11, 1957. When finished, the Glen Canyon Bridge was in itself a marvel of engineering: 1,271 feet (387 m) long and rising 700 feet (210 m) above the river, it was the highest bridge of its kind in the United States and one of the highest in the world. By 1959, the bridge itself was a major tourist attraction and it was said that "motorists driving miles out of their way just to be thrilled by its dizzying height".

Workers flooded into the dam site beginning in the mid-late 1950s, and the construction camp started out as a haphazardly organized trailer park that grew with the workforce. During the construction of the Glen Canyon Bridge, Reclamation also began planning a company town to house the workers. This resulted in the town of Page, Arizona, named for former Reclamation commissioner John C. Page. By 1959, Page had a host of temporary buildings, electricity, and a small school serving the workers' children. As the city grew, it gathered additional features, including numerous stores and a hospital, even a jeweler's. It was intended to serve a maximum population of eight thousand, accounting for the workers' families; the peak workforce would eventually exceed 2,500 in the busiest phases of construction.