Nickajack Dam
Encyclopedia
Nickajack Dam is a hydroelectric dam in Marion County
Marion County, Tennessee
Marion County is a county located in the U.S. state of Tennessee. As of 2000, the population was 27,776. Its county seat is Jasper.Marion County is part of the Chattanooga, TN–GA Metropolitan Statistical Area.-Geography:According to the U.S...

 in the U.S. state
U.S. state
A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

 of Tennessee
Tennessee
Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...

. It is one of nine dams on the Tennessee River
Tennessee River
The Tennessee River is the largest tributary of the Ohio River. It is approximately 652 miles long and is located in the southeastern United States in the Tennessee Valley. The river was once popularly known as the Cherokee River, among other names...

 owned and operated by the Tennessee Valley Authority
Tennessee Valley Authority
The Tennessee Valley Authority is a federally owned corporation in the United States created by congressional charter in May 1933 to provide navigation, flood control, electricity generation, fertilizer manufacturing, and economic development in the Tennessee Valley, a region particularly affected...

, which built the dam in the mid-1960s to replace the outdated Hales Bar Dam
Hales Bar Dam
Hales Bar Dam was a hydroelectric dam once located on the Tennessee River in Marion County, Tennessee, USA. The Chattanooga and Tennessee River Power Company began building the dam in 1905 and completed it in 1913, making Hales Bar one of the first major multipurpose dams and one of the first...

 6 miles (9.7 km) upstream. The dam impounds the 10370 acres (4,196.6 ha) Nickajack Lake
Nickajack Lake
Nickajack Lake is the reservoir created by Nickajack Dam as part of the Tennessee Valley Authority. The lake stretches from Nickajack Dam to Chickamauga Dam, and runs along the shores of Chattanooga, TN...

 and feeds into Guntersville Lake
Guntersville Lake
Guntersville Lake is located in north Alabama between Bridgeport and Guntersville. Created by Guntersville Dam along the Tennessee River, it stretches 75 miles from Guntersville Dam to Nickajack Dam...

. Nickajack Dam is named for a Cherokee
Cherokee
The Cherokee are a Native American people historically settled in the Southeastern United States . Linguistically, they are part of the Iroquoian language family...

 village once located just upstream from the dam (the site is now submerged). The village was the namesake for Nickajack Cave
Nickajack Cave
Nickajack Cave is a large, partially flooded cave in Marion County, Tennessee. It was partially flooded by the Tennessee Valley Authority's Nickajack Lake, created by the construction of Nickajack Dam in 1967. The entrance was originally 140 feet wide and 50 feet high...

, which was partially flooded by the reservoir.

Location

Nickajack Dam is located 424 miles (682.4 km) above the mouth of the Tennessee River, near the point where the states of Tennessee, Georgia
Georgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...

, and Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...

 meet. This stretch of the river marks a region where the river begins to exit the once treacherous Tennessee River Gorge
Tennessee River Gorge
The Tennessee River Gorge is a canyon formed by the Tennessee River once known as Cash Canyon. It is the fourth largest river gorge in the Eastern United States. The gorge is cut into the Cumberland Plateau as the river winds its way into Alabama from Tennessee. The Tennessee River Gorge is home...

 en route to the flatlands around Guntersville, Alabama
Guntersville, Alabama
Guntersville is a city in Marshall County, Alabama, United States and is included in the Huntsville-Decatur Combined Statistical Area. At the 2010 census, the population of the city was 8,197. The city is the county seat of Marshall County. Guntersville is located in a HUBZone as identified by the...

. The Sequatchie River
Sequatchie River
The Sequatchie River is a waterway that drains the Sequatchie Valley, a large valley in the Cumberland Plateau in Middle Tennessee.-Hydrography:The Sequatchie River's source is a massive spring which flows out of Head of Sequatchie Spring...

 empties into the dam's tailwaters, and the city of South Pittsburg
South Pittsburg, Tennessee
South Pittsburg is a city in Marion County, Tennessee, United States. It is part of the Chattanooga, TN–GA Metropolitan Statistical Area. The population was 3,295 at the 2000 census. South Pittsburg is home to the National Cornbread Festival.-History:...

 is just over 5 miles (8 km) downstream from the dam. Nickajack Lake stretches northeast for over 46 miles (74 km), all the way to the base of Chickamauga Dam
Chickamauga Dam
Chickamauga Dam is a hydroelectric dam on the Tennessee River in Chattanooga, Tennessee, USA. The dam is owned and operated by the Tennessee Valley Authority, which built the dam in the late 1930s as part of a New Deal era initiative to improve navigation and bring flood control and economic...

 in Chattanooga
Chattanooga, Tennessee
Chattanooga is the fourth-largest city in the US state of Tennessee , with a population of 169,887. It is the seat of Hamilton County...

. Tennessee State Highway 156 passes just south of Nickajack Dam, and Interstate 24
Interstate 24
Interstate 24 is an Interstate Highway in the Midwestern and Southeastern United States. It runs diagonally from Interstate 57 to Chattanooga, Tennessee, at Interstate 75....

 passes a few miles to the north.

Capacity

Nickajack Dam is 81 feet (24.7 m) high and 3767 feet (1,148.2 m) long. Its reservoir has 179 miles (288.1 km) of shoreline and 10370 acres (4,196.6 ha) of water surface. The dam's 10 spillway bays have a combined discharge of 360000 cuft/s. The electrical generating capacity of Nickajack is 104 megawatts.

Nickajack is serviced by a 600 by auxiliary lock that can lift or lower as many as nine large barges at a time 41 feet (12.5 m) between Guntersville Lake and Nickajack Lake. The dam's original design allowed for a 800 by main lock beside the auxiliary, but it was never completed. This lock, as well as every lock on the Tennessee river, is operated and maintained by the U.S. Army Corps of Engineers.

Background and construction

Before the completion of Hales Bar Dam
Hales Bar Dam
Hales Bar Dam was a hydroelectric dam once located on the Tennessee River in Marion County, Tennessee, USA. The Chattanooga and Tennessee River Power Company began building the dam in 1905 and completed it in 1913, making Hales Bar one of the first major multipurpose dams and one of the first...

 in 1913, the Tennessee River Gorge was one of the major impediments— along with Muscle Shoals
Muscle Shoals, Alabama
Muscle Shoals is a city in Colbert County, Alabama, United States. As of 2007, the United States Census Bureau estimated the population of the city to be 12,846. The city is included in The Shoals MSA. It is famous for its contributions to American popular music.-Geography:Muscle Shoals is located...

 and the Elk River shoals— to year-round navigation on the Tennessee River. Along with unpredictable water levels, the gorge was filled with numerous water hazards, some of which had been given nicknames such as "The Suck", "The Skillet", and "The Pan." In the early 1900s, the U.S. Army Corps of Engineers realized that a dam near the southwestern end of the gorge would flood the water hazards and eliminate the gorge's rapid downstream current. Chattanooga engineer Josephus Conn Guild offered to raise funds to build this dam in exchange for rights to the dam's electrical output. After receiving authorization from Congress in 1904, he organized the Chattanooga and Tennessee River Power Company
Chattanooga and Tennessee Electric Power Company
The Chattanooga and Tennessee Electric Power Company was formed in 1905 by Josephus C. Guild, Charles E. James and Anthony N. Brady to produce hydroelectric power and improving the navigation of the Tennessee River....

 (later TEPCO) in 1905, and the company began building Hales Bar Dam in October of that year. Hales Bar's weak limestone foundation— which hadn't been considered in the selection of the dam site— presented numerous obstacles from the outset, but the dam was finally completed in 1913.

In 1939, after a contentious court battle, TEPCO was forced to sell its assets— including Hales Bar Dam— to the Tennessee Valley Authority. The dam had been leaking since its construction, and TVA immediately initiated a series of foundation improvements that by 1943 had succeeded in halting the leaks. In 1960, however, the leaks had returned, spilling at an alarming 2000 cuft/s. Around the same time, TVA began expanding locks on its dams to at least 600 feet (182.9 m) to accommodate the increase in traffic the river had experienced since World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

, and it was determined that expanding the Hales Bar lock would be "prohibitively" expensive. Rather than spend the necessary expenses to upgrade Hales Bar, a decision was made in 1963 to build a new dam altogether on a more solid bedrock a few miles downstream.

The Nickajack Dam project was authorized January 9, 1964, and construction began April 1, 1964. Funding set aside for repair work on Hales Bar was transferred to the Nickajack project. The reservoir's construction— which basically involved extending the Hales Bar Reservoir 6 miles (9.7 km) downstream to Nickajack— required the purchase of 8300 acres (3,358.9 ha), 500 acres (202.3 ha) of which had to be cleared. 82 families and 8 miles (12.9 km) of roads had to be relocated. Two generators and several switchyard parts were moved from Hales Bar Dam to the new dam. Construction was completed on December 14, 1967, at a cost of $73 million. Operations at Hales Bar Dam were halted the following day, and by September 1968, Hales Bar Dam had been dismantled and its reservoir merged with Nickajack Lake.

External links

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