“But I Don’t Want It To Pop: The Import, Construction, and Future of the Shasta Dam”
California is blessed with a wide variety of terrain, weather, resources, and people. Unfortunately for the state, historical forces worked against it, sending most of the people to the far south while most of the resources, namely water, remained in the north. At the dawn of the twentieth century the people of California had decided to take it upon themselves to correct that small inconsistency in geography. Over the course of the next forty years, canals, aqueducts, reservoirs, and cisterns were constructed throughout the state to send the bounty of the north’s supply of dihydrogen monoxide to the dry and thirsty lands of Los Angeles and the San Joaquin. One of those efforts was the Central Valley Project, the most ambitious one to date, and one of the major keystone facilities is the Shasta Dam and Reservoir. A microcosm of California’s trials and triumphs, challenges and concerns, it was undertaken as not just another New Deal public works project, but had California’s own particular flair for ascetics, dramatics, and grandeur.
The Sacramento River is, like most California rivers, a seasonal river; its flow changes over the year as its watershed is fed more by runoff from snowpack and the glaciers of Mt. Shasta, rather than a steady source of rainfall. That rainfall, however, is not spread out evenly over the state. Due to the prevailing weather patterns of the North Pacific, the Sacramento River valley receives twice the rainfall of the San Joaquin River valley. However, the southern area of this Central Valley is prized for its longer growing season, which can be up to three weeks longer when measured at the extremes of the valley. During the early part of the rainy season, the precipitation falls as snow on the northern Sierra Nevada and southern Cascades. At the end of this period, however, the temperature has risen and the rain is supplemented by melt waters and therefore the Sacramento River is prone to flooding, far more than the San Joaquin. These floods would be severe in 1924 and 1925, wiping out timberland in the Kenneth region and covering the soil with ashen mud, making it “oxygen poor.” This seasonable flow and its attendant floods had an impact farther downstream, in the Sacramento River’s delta as it entered San Francisco Bay. As the bay expanded its dockside infrastructure, it was noticed that during the dry period, when the river was at its lowest, that the saltwater from the bay would back up into the delta causing severe problems. This backflow damaged the ecosystem of the delta and the farming that went on in the area surrounding it (now mostly rice and tomatoes), introduced salt water organisms that were not planned for (a teredo, a wood-burrowing saltwater worm, infestation destroyed docks in the Suisun bay area), and deprived the cities of Pittsburg and Antioch of their municipal water supplies when the salinity reached a high of 65% of the ocean.
By the 1930s, the need to control the Sacramento River was self evident, and since the river was to be controlled, why not harness it as well for work? Californian voters were presented a proposal of unprecedented size, a billion dollar project that would create a huge system of dams, levees, and canals that would span the length of the state. The Central Valley Project was sent to the voters in 1933, where it was approved even as the Great Depression was occurring. The state was unable to completely raise the bonds necessary to finance the project, but the new FDR administration stepped in with New Deal money through the Bureau of Reclamation, the repayment schedule defined within the Harbours and Rivers Act of 1937, which made it subject to the 160 acre-feet limit for free water.
The money secured, the dam was planned and constructed, and what a dam it was. Only one site, the Kenneth site, was ever seriously considered and surveyed, and a compacted base was set up that would support a dam 800 feet high. This height was never reached, however, as it was decided to cap the dam at the 602 foot mark, with the possibility of expansion in the future. Like most large dams of the era, it was a curved-concrete gravity dam, but due to the seismic nature of California, the amount of concrete poured made it the second largest dam by volume in the United States, second only to the Grand Coulee Dam on the Colombia. As such, there were bound to be problems and delays in its construction. Right from the start, there was consternation from labor. Since the money had come from the Federal Government rather than the state, the Bureau of Reclamation insisted that federal wage scales were to be used for union contracted labor. The first work stoppage occurred when the construction of the Southern Pacific Railroad (SPRR) bridge was halted, trying to link the rail and road improvements and detours to the dam project proper. Labor itself slowed progress on the construction of the dam when the conflict between the AFL and CIO spilled onto the spillway, halting work on the concrete sluices that guided the water around the dam site in 1939. Mother Nature had something to say about the project as well. An above average stream flow halted work in 1938, a precursor to a far more destructive flood in 1940, which killed a dozen or so people. Finally, the 1940s brought on new delays: material shortages due to the war effort. In 1940, some of the steel to be used in the dam was diverted for shipbuilding. 1941 brought shortages in concrete. By 1942, mobilization had robbed the site of most of its initial workforce. Work continued until, finally, on 20 June 1945, the Bureau of Reclamation accepted the dam at a finish height of 602 feet.
Shasta Dam and Reservoir is representative of other public water works in California during this period. Many of the larger dams and water projects were designed to be impressive and offered distinct designs to make them more appealing – California flair. The Mulholland spillway fell down into Los Angeles into the San Fernando Valley, a series of steps making a tiered waterfall that could have been served just as well by a plain sluice or a grey pipe, as evidenced by the pipes at the Kern County Grapevine pumping station. The Hollywood Reservoir sat behind a curved dam that offered breathtaking views of Los Angeles; after the collapse of the similar St. Francis Dam, the Mulholland Dam was reinforced by earthworks to the point where it looks like a natural feature of the area. Even some of the smaller projects were done with an eye for the dramatic, such as the art-deco Sepulveda Dam. When the engineers accessorized Shasta Dam, they gave it a large central spillway. Capable of releasing 186,000 cubic feet of water per second, the 487 foot contained spillway in the center of the dam became the tallest man made waterfall. The infrastructure was also given a touch of the artistic as well. The overpass for Interstate 5 over the main section of Shasta Lake sits at a significant height over the water level, the roadway laid in anticipation of an 800 foot dam, providing a panoramic view of the lake. In addition, a sly civil engineer laid out the northbound bridge with a particular aim: Once the roadway levels out to traverse the lake’s valley, the northbound traveler finds himself driving almost directly toward the 14,162 foot stratovolcano, Mt. Shasta, which dominates the skyline. These touches to a civil works project are fascinating looks into the flair of Californian civil works projects, starting with the ambitious Golden Gate.
The job complete, the lake, dam, and river was put to work. Massive hydroelectric plants were installed at the base of the dam to utilize the flow of water. When the original complex was done, five generators powered by the Sacramento generated a peak output of one hundred forty two thousand kilowatts in 1954. In the 1990s, utilizing money from the California Valley Project Improvement Act, these old generators were replaced. Brand new and modern designs replaced the long-serving turbines and output was increased to six hundred fifty nine thousand kilowatts, a 460% increase in electrical generation. The National Parks Service, coupled with its California counterpart, turned the lake into a huge recreational area. Shasta Lake became known for its beautiful scenery, fishing, a large houseboat community in the early 80s, and for attractions such as the Shasta Caverns on the McCloud arm.
All this development, however, has brought its share of challenges. People moved to the north valley in significant numbers during the construction, and communities such as Redding exploded with new residents. As noted, the rail and road lines were routed above the lake surface instead of around it, and as such, still serves as the primary connection between California and the cities and farming communities of Oregon and Washington. Coupled with associated pollution from the growth of mining, logging, and agriculture in the area, the upper Sacramento has become closely monitored for pollution, as it feeds into the reservoir. The dangers involved with this came into sharp focus when a train derailed, sending a car filled with the pesticide VAPAM (sodium methyl dithcarbonate) into the Sacramento just south of Dunsmuir in 1991. Once in the water, reactions turned it into MITC (methyl isothiocyanate) which was devastating to the fish population in the river. This substance entered the reservoir on the Sugarloaf arm, and sank into the lake. The lake is large enough to become “stratified”, with various thermal layers separating waters of different density. The chemical became buoyant at a depth of eight to twelve meters and remained there. As the MITC spread into the lake, it passed through a special aerating station, used to oxygenate the water for the fish. Oxygen is a catalyst, and as the chemical passed by, the station’s process vastly increased the breakdown of the chemical into less-than-toxic forms. The study of the process after the accident became a cautionary tale (the tank car was unmarked) and provided a system for dealing with large chemical spills into water supply reservoirs.
The final challenge awaiting Shasta dam is the future. California is struggling to provide enough water for its increasing population, and existing reservoirs are being strained to provide it. Studies are being undertaken now to examine the feasibility of raising Shasta Dam by up to eighteen and a half feet. This would drown another two thirds of a mile of the McCloud River, well loved by sport fishermen, naturalists, and the Winnemem Wintu tribe. The tribe claims that since it never received recognition from the Federal Government during the initial construction, its efforts to preserve their culture and access to sacred lands has been limited; further sacred areas would be placed underwater if the dam was expanded. Sport fishermen lament the loss of some of the most sought after fishing locales in the state; the rivers are dotted with lodges and camps. Naturalists want the state to concentrate on other water projects, smaller reservoirs, and ocean desalinization plants. Wrangling over these issues killed a study on the expansion of the dam in 1982; the Bureau of Reclamation admits little is likely to happen in the near future.
In a state where water and power is king, Shasta Dam sits rightly so as the crown jewel of the state’s biggest water project. Almost seven million cubic feet of concrete have tamed one of the more quirky rivers in America. In the process, several things happened. Large amounts of electricity were generated, industry and communities were created and expanded, and water was stored for lean times and controlled during floods. A whole recreational complex was created, done with the simple panache that California had brought to its public works projects. With success have come problems, however. The communities that have expanded have increased traffic in the area, increasing pollution as industry has risen. Transportation on a large scale still passes north and south across the lake, and accidents such as the 1991 Dunsmuir spill, while infrequent, are inevitable. Finally, California itself has grown beyond the capacity of the dam itself. The state looks to expand upon its strong base for future growth, but opposition has marshaled its forces to preserve the area from further development. It is in this light that the state of California looks north and ponders its future under the shadow of Mount Shasta.
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