Shasta Dam

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Shasta Dam
Shasta Dam
Shasta dam seen from above. Photo by Bureau of Reclamation
Official name Shasta Dam
Impounds Sacramento River[1]
Creates Shasta Lake
Locale Shasta Lake City, California
Maintained by US Bureau of Reclamation[1]
Length 3,460 ft (1,055 m)[1]
Height 602 ft (183 m)[1]
Width (at base) 543 ft (165.5 m)
Construction began 1938
Opening date 1945[1]
Reservoir information
Capacity 4,661,860 acre-feet[1]
Catchment area 6,665 sq mi (17,260 km²) [2]
Surface area 30,310 acres[1]
Geographical Data
Coordinates 40.71861° N 122.41778° W[3]

Shasta Dam is a curved gravity concrete dam (National ID No. CA10186) on the Sacramento River above Redding, California near Shasta Lake City built between 1938 and 1945.[1] Like another curved gravity dam (Hoover Dam), it was a continuous pour concrete project, and in its day, ranked as one of the great civil engineering feats of the world. The dam is 602 ft (183 m) high and 3,460 ft (1,055 m) long, with a base width or thickness of 543 ft (165.5 m).[1] The reservoir created behind Shasta Dam is known as Shasta Lake and is a popular recreational boating area.

Contents

[edit] History

Shasta Dam under construction, June 1942
Shasta Dam under construction, June 1942

[edit] Central Valley Project

California's Central Basin extends nearly 500 miles from the Sacramento River in the north and reaches the San Joaquin River in the south. European development of the region began in earnest after gold was discovered in 1849, and can be characterized by three overlapping stages of agricultural progress.[4] It began with cattle ranching, followed by dry farming of grain, and presently the specialized and heavily irrigated farming practices of today. While demand for water remains high, average rainfall can fluctuate significantly throughout the Central Basin, ranging from as few as five inches annually in the south to as many as 30 inches in the north.[4] Furthermore, greater than 75 percent of the yearly precipitation occurs in the five months between December and April, making it difficult to sustain crops during the summer months. "Agriculture in the Central Valley prove[s] almost as much a gamble as prospecting for gold. When nature cast[s] the die, the roll [can] literally result in flood or famine."[4] Complicating matters further, the northern end of the basin faces issues of salinity control. At certain times during the year, saltwater from San Francisco Bay can move inland during high-tides, making water unusable for irrigation and other industries. As a result, in the interests of creating a sustained, year-round supply of water, as well as controlling salinity of the Central Basin's freshwater, federal legislature for the Central Valley Project (CVP) was passed in 1933.[4]

Today, a system of 20 dams, 500 miles of canals, and other mechanisms for water conservation and distribution sustain six of California's 10 most productive agricultural counties.[4] This complex water system also provides fresh water for urban centers like San Francisco. Of the nearly nine million acre-feet of water in its management, the CVP annually delivers seven million acre-feet to these causes. Additionally, the 11 power plants in the region generate 5.6 billion kilowatt-hours of electricity–enough to provide for approximately two million people.[4] The Central Valley Project also oversees natural preservation efforts, allocating over one million acre-feet of water annually to conserve fish and wildlife habitats. The CVP also assists in wetland protection efforts. Estimates have shown that the federal government's initial investment of $3 billion has resulted in $300 billion dollars in returned growth of agricultural and other related industries.[4]

[edit] Shasta Division and Shasta Dam

The Shasta division of the Central Valley Project consists of Shasta Dam and Shasta Lake, the Shasta power plant, as well as the Keswick Dam and its power plant. Located ten miles north of Redding on the Sacramento River, Shasta Dam is positioned to "catch the headwaters of the network of Central Valley Project waterways and channel the water southward." Shasta Dam is the second-largest dam in the United States, behind the Grand Coulee Dam in Washington State.[5] It measures 602 feet in height and is 3,460 feet across. Construction on the dam began in 1938 and finished seven years later in 1945.[5] Feeding the Shasta power plant, the dam's spillway is the largest man-made waterfall in the world.[5] In addition, Shasta Lake is the largest man-made reservoir in California, containing about 4.5 million acre-feet of water and consisting of 365 miles of shoreline. In total, at least 47 square miles of land are now submerged under the lake.[5]

The area around the region that would later become Shasta Lake was largely unpopulated by Europeans until 1840. However, population was estimated to grow at a staggering rate of 40 percent after the beginning of construction on the dam, and smaller increases have persisted over the years. At the time of the 1990 Census, Shasta County was home to 147,036 people.

In its role of controlling salinity, the dam prohibits water from San Francisco Bay to move inland and damage irrigation efforts. Similarly, in tandem with the Keswick Dam downriver, it operates as a flood control, managing the flow of water from Shasta Lake. The power plant at Shasta Dam has a maximum generating capacity of 676,000 kilowatts, contributing to the 5.6 billion kilowatt-hours of electricity produced by all elements of the Central Valley Project.[5] After concerns about the impact of the dams on wildlife were raised in the 1970s, efforts were made to protect fish habitats on the Sacramento River. As a result, a minimum flow of water is maintained in the Shasta Division, allowing certain species of salmon and other fish to safely maneuver the River as well as offering optimal conditions for spawning.[5]

"Federal and state project planners envisioned Shasta Dam as the key to the Central Valley Project. Shasta would perform several duties for the project, including water storage, to release for irrigation and salinity control in the Delta; flood control, to protect communities along the Sacramento River, long afflicted by flood waters; and power generation."[5]

Further efforts were undertaken at Shasta to provide a Chinook salmon spawning and rearing facility. Water from Shasta Lake provides irrigation for crops in the Sacramento and San Joaquin Valleys valued at an estimated $256 million in 1990, as well as a supplemental area of 460,000 more acres of cropland. Finally, Shasta Lake provides recreation such as boating, fishing, swimming, and other water activities. Home sites have also been developed along the shore, as well as resorts that cater to the needs of vacationers.[5]

[edit] Shasta Dam Expansion

[edit] Why

Since its completion in 1944, the Shasta Dam has successfully prevented water shortages in agricultural lands and floods amounting up to $5 billion in the Central Valley of California. It has also carried out several other functions, including, but not limited to, municipal and industrial (M&I) water supply, the generation of hydroelectric power, and recreation. Thanks to the Shasta Dam the Sacramento-San Joaquin Delta is free of saline ocean waters and fish such as the Chinook salmon, which suffered a great decline in population, are slowly climbing in number under protection and care by the Livingston Stone National Fish Hatchery.[5] However, in 1999, the Central Valley requested the United States Department of the Interior, Bureau of Reclamation, Mid-Pacific Region (Reclamation) for an evaluation of the Shasta Dam and the possible expansion due to the increasing needs for M&I water supplies: Shasta Lake Water Resources Investigation (SLWRI).[6]

As of 2006, California’s population was around 36.5 million people and according to California Senator Dianne Feinstein, the state is growing at an alarming rate of 700,000 to 1 million people per year. Considering this rate of growth, the Central Valley Project Improvisation Act (CVPIA) and California Bay-Delta Program (CALFED) both realized the need to expand the dam to accompany the need for more water.[7] The primary goals of the SLWRI are to first increase the survival of Chinook salmon by creating a larger pool of cold water and to secondly, and more importantly, increase the water supply and reliability of the water used for agricultural, M&I, and environmental purposes. There are also secondary goals which include the preservation and restoration of ecosystems in and around the Shasta Dam and Sacramento River. With the expansion of the dam also comes the further prevention of flood damages since the dam will be able to hold a larger pool of water. [8]Lastly, because the dam will be able to hold a larger volume of water, it will also be able to generate more electricity with the extra amount of water it can retain. Hence, the raising of the dam wall in the expansion of the Shasta Dam will primarily have a two-fold benefit for California: a larger water supply, of which the degree will be dependent upon how much the wall will be raised, and a greater level of electricity for the increased population(Table 1).[9]

In terms of hydroelectricity that can be generated, the SLWRI calls for the construction of another power plant in addition to the existing power plant. The current power plant usually generates around 578 Megawatts (MW) while at maximum operation, it can generate up to 676 MW. The new power plant will be larger in size and will either contain five 215 MW turbines or five 260 MW turbines depending on the level of expansion. For the five 260 MW turbines, 1300 MW of power will be produced in addition to the existing power plant electricity production and the five 215 MW turbines will produce 1075 extra MW. This will accommodate the near exponential growth of the California population.[6]

Table 1. Enlarged wall and its impacts on water pool size and economy
Wall Elevation (ft.) Extra Water Added (acre-ft.) Impact
6 290,000 Support ~1.1 million people for 1 year
18 636,000 Support ~2.5 million people for 1 year
200 14,000,000 Support ~10 million people for 1 year

[edit] Why Not

The raising of the dam has much further consequences besides the increased water supply and higher generation of electricity. At the heart of the problem lies the Winnemem Wintu Tribe, a Native American tribe that has not been granted federal recognition despite the decree of the Assembly Joint Resolution 39 (AJR39). The Winnemem Wintu suffered great losses when the dam was constructed in 1944 – and subsequently opened in 1945 – because 90% of the land that went under water included burial grounds as well as sacred sites. Although an upwards of 180 burials sites were moved to Shasta Lake City, the Wintu were not compensated for the approximately 4000 acres of land that were lost underneath the Shasta Dam waters. The raising of the dam will bring even further loss of sacred lands for the Wintu who have yet to be allotted land promised 60 years ago. More specifically, 26 additional village sites with burial grounds and prayer rocks will be going under water upon the raising of the dam even 6 feet.[7]

The raising of the dam will also lead to the flooding of canyons while endangering wildlife and forests in the surrounding areas. This will in turn increase the number of houseboats, dried trees, and sterile lake beaches.[7] In other words, while it may benefit some fish species, it will be at the cost of other ecosystems nearby having one reassess the benefits of the issue. For example, California wild trout will lose the Upper Sacramento and McCloud Rivers – two prominent trout habitats - to inundation.[10]

Shasta County Supervisor Molly Wilson and other politicians who are opposed to the raising of the dam argue that the amount of water gained via the dam raise is trivial and will not significantly alleviate any of the water concerns frustrating California. They strongly suggest the creation of additional reservoirs elsewhere instead of raising the dam. They also argue that the reason for all these concerns is the excessive use of water and electricity. The most efficient method of meeting the needs of the California population, they argue, is for each person to conserve water and electricity. They also pointed out the fact that the extra body of water will be available to the farmers of California, but not affordable. Calculations show that water from raised dam will cost between $220 and $270 per acre-ft. Considering most farmers currently pay anywhere between $50 to $150 per acre-foot, the new prices will be burdensome for farming.[11]

According to the Reclamation’s appraisal of the Shasta Dam expansion, two major transportation routes will have to be relocated and replaced. As the largest railroad in North America, the Union Pacific Railroad has served 23 states on the national level while keeping the U.S. connected with Canada and Mexico on the international level. A 200 feet dam wall raise will lead to the replacement of 35.8 miles of tracks, the excavation of 24 million yd3 of land, and the embankment of 29 million yd3. Interstate 5 will also have to be replaced for the 200 feet dam wall enlargement – 18.5 miles of reconstruction to be exact. In addition, 23 million yd3 must be excavated while 19 million yd3 embanked, all of which take time, labor, and have hefty price tags.[6]

On the subject of hefty price tags, the raising of the dam wall itself comes at high costs(Table 2).[6] Not only does it cost millions to build the actual concrete wall, but there are also many hidden costs that are not apparent at first. Preconstruction, there are construction management costs and costs involved with engineering and designing of the wall elevation. While the construction is taking place, there are costs related to the replacement of Interestate 5 and the Union Pacific tracks, as well as the relocation of many recreational sites and the construction of the new power plants. Postconstruction, there are annual maintenance costs, which are on the million dollar scale.[6]

Table 2. Average Costs for per acre-foot of storage
Description Crest Elevation 1084 (4 foot raise) Crest Elevation 1180 (100 foot raise) Crest Elevation 1280 (200 foot raise)
Total Field Cost 82,700,000 2,542,890,000 3,805,305,000
Total First Cost 107,510,000 2,924,324,000 4,376,154,000
Total Investment Cost 122,281,000 3,889,729,000 5,810,927,000
Added Storage (acre-feet) 290,000 3,920,000 9,340,000
Cost per acre-foot based on First Cost 371 746 469
Cost per acre-foot based on Total Investment Cost 422 992 622

[edit] The Woes of the Winnemem Wintu Tribe

Although the Shasta Dam has proven to be vastly beneficial for most of California's residents, it has taken lasting detrimental effects on the state's forgotten Native people. The Winnemem Wintu tribe of California has witnesses the inundation of many of its landmarks and sacred sites.

According to Caleen Sisk-Franco, the tribe's chief and spiritual leader, 14,000 Winnemem Wintu natives occupied the land around the McCloud River in the 1850s and by 1900, only 396 had survivied.[12] In 1945, when soldiers from the Winnemem Wintu tribal members returned from World War II, they found the Shasta Dam completed and their homes underwater. Like all other Native American tribes, the number of tribesmen has drastically plummeted and there are now just around 125 existing members.[12]

At the initial construction of the Shasta dam in the 1930s, the Winnemem Wintu natives agreed to give up a large portion of their land for the sake of the Californians' ever growing demand for water, but unfortunately never received anything for their generosity. According to Claire Hope Cummings, the Winnemem Wintu lawyer for over 15 years, at the initial construction of the dam, Congress promised the Wintu tribe a replacement burial ground but the promise was never granted.[12]

Not only is the tribe struggling to hold on to whatever existing land they have, but the Bureau of Indian Affairs has not recognized the Winnemem Wintu people as an official Native American Tribe. Without official status it becomes increasingly difficult for the tribe to voice its opinions and concerns when it comes to issues like the construction and expansion of the Shasta Dam. "Any rise in Lake Shasta will drown Wintu sacred sites, including 26 village sites with burial grounds and prayer rocks," Cummings says.[12]

In September 2004, the tribe held its first war dance since 1887 to express their opposition and discontent with the proposed expansion of the dam.[13] Because the war dance was to take place during the third anniversary of the infamous 9/11 terrorists attacks, the United States government initially prohibited the use of traditional weapons for fear of national security. However, after much rebuttal from the Winnemem Wintu, the U.S. Government eventually allowed the tribe to conduct the traditional war dance as intended.[13]

Landmarks crucial to the development of the tribe also faces grave danger. Puberty Rock, which is already under water for about half of the year due to fluctuations in water levels, would be completely underwater year-round if the dam were raised. The coming of age ceremony that takes place at Puberty Rock is where they girls of the tribe become women. During this ceremony, the girl must spend four days on one side of the McCloud River and take in advice from all of the influential women in her life, like her aunts, friends and elders. To test her endurance and to make sure she is ready for womanhood, the girl must walk upriver during the day and spend her nights in a bark hut. After the four days, the girl swims across the river and comes out as a woman. With the expansion of the dam Puberty Rock will be inaccessible.[13]

Even the children's rite of passage would become impossible to complete. If the dam is raised any further, Children's Rock will become inundated and thus inaccessible. Here, the children of the tribe place their hands on the rock to receive blessings to make them good people. By doing so, they are also able to comprehend what special gifts they have as well as providing them with clarity, explains Franco.

Also at risk are the burial grounds where the Kaibai Creek massacre victims are buried. In 1854, white settlers murdered more than 40 Winnemem Wintu men, women and even children at Kaibai Creek. The bones of passed natives must remain in peace in order to allow the spirit to move along but the expansion of the Shasta Dam would not allow for this to occur, disturbing the ceremonial balance of the tribe.[13]

[edit] Trivia

  • Shasta Dam is higher than the Washington Monument.
  • It contains enough concrete to build a sidewalk 3 feet (0.91 m) wide, 4 inches thick around the world at the Equator.
  • Second largest dam is the US next to Grand Coulee Dam on the [[[Columbia River]] is Washington State [14]
  • The face of the dam covers 31 acres, which is equivalent to six football fields and their stadiums[14]
  • The spillway is 487 feet and is the largest man-made waterfall in the world = 3x the height of Niagara Falls[14]
  • Shasta Lake = largest man-made reservoir in California[14]

[edit] References

[edit] External links

Wikimedia Commons has media related to:
  • Shasta Dam, Bureau of Reclamation, U.S. Dept. of the Interior

Coordinates: 40°43′N, 122°27′W

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