John H. Kerr Dam
Encyclopedia
John H. Kerr Dam is concrete
gravity-dam
located on the Roanoke River
in Virginia
, creating Kerr Lake
. The dam
was built by the U.S. Army Corps of Engineers between 1947 and 1953 for the purposes of flood control
, and hydropower
. The dam also serves wildlife resources, forest conservation, and public recreational uses. The John H. Kerr Dam currently produces over 426 million KWh of electricity annually and has prevented over $385 million in flood damage since completion. The dam is named after John H. Kerr
, a Congressman from North Carolina
who was instrumental in authorizing the construction.
Construction of the John H. Kerr dam was authorized by the 78th United States Congress
in 1944 with the Flood Control Act of 1944
but did not commence until 1947. The site was selected because of the granite
in the area that could support a large concrete
dam
. During early construction, the project was called Buggs Island Lake after a downstream island which was named after Samuel Bugg, an 18th Century early pioneer. The 82nd United States Congress
renamed the project the John H. Kerr Dam later in 1951.
The John H. Kerr Dam Project consisted of a dam, powerhouse
and switchyard. The dam was built in 53 sections called monoliths. A grout
ing tunnel or gallery was built in order to fill gaps between the dam and foundation with concrete. The spillway
consists of 22-tainter gate
s for overflow and at the base of the dam, 6-sluice gates were installed to maintain downstream flows. Construction was completed and the dam was opened in 1953.
plant within the John H. Kerr Dam contains 7 vertical Francis units
capable or producing 227,000 KW
or 227 MW
. Six large generators
within the power-plant produce 32,000 KW each and one smaller unit produces 12,00 KW. The hydro-power plant operates at about 83% efficiency.
58% of the power sold is transmitted to the Virginia Electric Power Company
and 42% to the Carolina Power & Light
Company. Overall, the power is regulated by the Southeastern Power Administration
and about one half of the power is transmitted to various government preference customers such as rural Cooperatives.
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...
gravity-dam
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...
located on the Roanoke River
Roanoke River
The Roanoke River is a river in southern Virginia and northeastern North Carolina in the United States, 410 mi long. A major river of the southeastern United States, it drains a largely rural area of the coastal plain from the eastern edge of the Appalachian Mountains southeast across the Piedmont...
in Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
, creating Kerr Lake
Kerr Lake
Kerr Lake is a reservoir along the border of the U.S. states of North Carolina and Virginia created by the John H. Kerr Dam...
. The dam
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...
was built by the U.S. Army Corps of Engineers between 1947 and 1953 for the purposes of flood control
Flood control
In communications, flood control is a feature of many communication protocols designed to prevent overwhelming of a destination receiver. Such controls can be implemented either in software or in hardware, and will often request that the message be resent after the receiver has finished...
, and hydropower
Hydroelectricity
Hydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy...
. The dam also serves wildlife resources, forest conservation, and public recreational uses. The John H. Kerr Dam currently produces over 426 million KWh of electricity annually and has prevented over $385 million in flood damage since completion. The dam is named after John H. Kerr
John H. Kerr
John Hosea Kerr , grand-nephew of John Kerr and relative of John Kerr, Jr., was a Democratic Party member of the U.S. House of Representatives representing North Carolina from 1923 to 1953...
, a Congressman from North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
who was instrumental in authorizing the construction.
Background & Construction
78th United States Congress
The Seventy-eighth United States Congress was a meeting of the legislative branch of the United States federal government, composed of the United States Senate and the United States House of Representatives. It met in Washington, DC from January 3, 1943 to January 3, 1945, during the last two years...
in 1944 with the Flood Control Act of 1944
Flood Control Act of 1944
The Pick-Sloan Flood Control Act of 1944 , enacted in the 2nd session of the 78th Congress, is U.S. legislation that authorized the construction of numerous dams and modifications to previously existing dams, as well as levees across the United States...
but did not commence until 1947. The site was selected because of the granite
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...
in the area that could support a large 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...
dam
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...
. During early construction, the project was called Buggs Island Lake after a downstream island which was named after Samuel Bugg, an 18th Century early pioneer. The 82nd United States Congress
82nd United States Congress
The Eighty-second United States Congress was a meeting of the legislative branch of the United States federal government, composed of the United States Senate and the United States House of Representatives. It met in Washington, DC from January 3, 1951 to January 3, 1953, during the last two years...
renamed the project the John H. Kerr Dam later in 1951.
The John H. Kerr Dam Project consisted of a dam, powerhouse
Power station
A power station is an industrial facility for the generation of electric energy....
and switchyard. The dam was built in 53 sections called monoliths. A grout
Grout
Grout is a construction material used to embed rebars in masonry walls, connect sections of pre-cast concrete, fill voids, and seal joints . Grout is generally composed of a mixture of water, cement, sand, often color tint, and sometimes fine gravel...
ing tunnel or gallery was built in order to fill gaps between the dam and foundation with concrete. The spillway
Spillway
A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically being the river that was dammed. In the UK they may be known as overflow channels. Spillways release floods so that the water does not overtop and damage or even destroy...
consists of 22-tainter gate
Tainter gate
The Tainter gate is a type of radial arm floodgate used in dams and canal locks to control water flow. It is named for Wisconsin structural engineer Jeremiah Burnham Tainter....
s for overflow and at the base of the dam, 6-sluice gates were installed to maintain downstream flows. Construction was completed and the dam was opened in 1953.
Hydro Power-Plant
The hydro-powerHydroelectricity
Hydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy...
plant within the John H. Kerr Dam contains 7 vertical Francis units
Francis turbine
The Francis turbine is a type of water turbine that was developed by James B. Francis in Lowell, Massachusetts. It is an inward-flow reaction turbine that combines radial and axial flow concepts....
capable or producing 227,000 KW
Watt
The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
or 227 MW
Watt
The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
. Six large generators
Electrical generator
In electricity generation, an electric generator is a device that converts mechanical energy to electrical energy. A generator forces electric charge to flow through an external electrical circuit. It is analogous to a water pump, which causes water to flow...
within the power-plant produce 32,000 KW each and one smaller unit produces 12,00 KW. The hydro-power plant operates at about 83% efficiency.
58% of the power sold is transmitted to the Virginia Electric Power Company
Dominion Resources
Dominion Resources Inc. , commonly referred to as Dominion, is a power and energy company headquartered in Richmond, Virginia that supplies electricity in parts of Virginia and North Carolina and supplies natural gas to parts of West Virginia, Ohio, Pennsylvania, and eastern North Carolina...
and 42% to the Carolina Power & Light
Carolina Power & Light
Carolina Power & Light was an electrical generation, transmission, and distribution utility based in Raleigh, North Carolina. The company was founded on July 13, 1908 as the result of the merger and buyout of numerous small, private, and financial distressed utilities across the state...
Company. Overall, the power is regulated by the Southeastern Power Administration
Southeastern Power Administration
The Southeastern Power Administration is a United States Power Marketing Administration with responsibility for marketing hydroelectric power from 23 water projects operated by the U.S...
and about one half of the power is transmitted to various government preference customers such as rural Cooperatives.