The Don N. Holt Bridge is a parallel chord, three-span continuous, modified Warren-type

truss bridge A truss bridge is a bridge whose load-bearing superstructure is composed of a truss, a structure of connected elements, usually forming triangular units. The connected elements, typically straight, may be stressed from tension, compression, or ...

that carries Interstate 526 (I-526) over the Cooper River between Charleston and

North Charleston North Charleston is a city in Berkeley, Charleston, and Dorchester counties in the U.S. state of South Carolina.City Planning Department (2008-07)City of North Charleston boundary map. City of North Charleston. Retrieved January 21, 2011. As ...

. It was built in 1992 by the

South Carolina Department of Transportation The South Carolina Department of Transportation (SCDOT) is a government agency in the US state of South Carolina. Its mission is to build and maintain roads and bridges and administer mass transit services. By state law, the SCDOT's function an ...

and was designed by HNTB Corporation. The bridge provides a connection between the communities east of the Cooper River, including Mount Pleasant and

Daniel Island Daniel Island, South Carolina is a body of land located in the city of Charleston, South Carolina, United States. Named after its former inhabitant, the colonial governor of the Carolinas, Robert Daniell, the island is located in Berkeley Co ...

, to

and I-26. It is part of a major

hurricane A tropical cyclone is a rapidly rotating storm system with a low-pressure area, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depending on its ...

evacuation route for the area. The Don Holt Bridge is adjacent to a

Kapstone KapStone Paper & Packaging (formerly Stone Arcade Acquisition Corporation) was an American pulp and paper company based in Northbrook, Illinois. It was founded in 2005 as Stone. Since November 2018 it has been a subsidiary of WestRock Company. ...

(formerly

MeadWestvaco MeadWestvaco Corporation was an American Packaging and labeling, packaging company based in Richmond, Virginia, Richmond, Virginia. It had approximately 23,000 employees. In February 2006, it moved its corporate headquarters to Richmond. In March ...

)

paper mill A paper mill is a factory devoted to making paper from vegetable fibres such as wood pulp, old rags, and other ingredients. Prior to the invention and adoption of the Fourdrinier machine and other types of paper machine that use an endless belt ...

. In the mid 1980s, prior to construction of the bridge, owners of the mill filed a lawsuit to stop the bridge because the

bridge deck A deck is the surface of a bridge. A structural element of its superstructure A superstructure is an upward extension of an existing structure above a baseline. This term is applied to various kinds of physical structures such as buildin ...

would be at the same height as smokestacks from the mill. In certain weather conditions, the smokestacks produce a fog which could blind drivers and place the mill at risk for lawsuits from drivers. The lawsuit was settled by mandating that a

road weather information system A Road Weather Information System (RWIS) comprises automatic weather stations (AWS) (often technically referred to as Environmental Sensor Stations (ESS) as they also cover non-meteorological variables) in the field, a communication system for dat ...

(RWIS) be included in the bridge project. The RWIS was designed to detect reduced visibility on the bridge and "to inform drivers of dense fog conditions, reduce traffic speeds, and guide vehicles safely through the fog-prone area." The system uses

variable-message sign A variable- (also changeable-, electronic-, or dynamic-) message sign or message board, often abbreviated VMS, VMB, CMS, or DMS, and in the UK known as a matrix sign, is an electronic traffic sign often used on roadways to give travelers info ...

s and illuminating pavement lights (similar to a

runway centerline lighting system In aviation, a runway is an elongated, rectangular surface designed for the landing and takeoff of an aircraft. Runways may be a human-made surface (often asphalt, concrete, or a mixture of both) or a natural surface (grass, dirt, gravel, ic ...

). As of May 2003, there were no fog-related crashes. The bridge was named for Don N. Holt who served in the

South Carolina House of Representatives The South Carolina House of Representatives is the lower house of the South Carolina General Assembly. It consists of 124 representatives elected to two-year terms at the same time as U.S. congressional elections. Unlike many legislatures, seatin ...

and was in the insurance business.Concurrent Resolution
of the

South Carolina General Assembly The South Carolina General Assembly, also called the South Carolina Legislature, is the state legislature of the U.S. state of South Carolina. The legislature is bicameral and consists of the lower South Carolina House of Representatives and ...

References

Cornell University Case Study of the Don Holt Bridge

Map showing boundaries of City of Charleston
{{Crossings navbox , structure = Crossings , place = Cooper River , bridge = Don N. Holt Bridge , bridge signs = I-526

, upstream =

CSX CSX Transportation , known colloquially as simply CSX, is a Railroad classes, Class I freight railroad company operating in the Eastern United States and the Canadian provinces of Ontario and Quebec. Operating about 21,000 route miles () of trac ...

railroad Rail transport (also known as train transport) is a means of transport using wheeled vehicles running in railway track, tracks, which usually consist of two parallel steel railway track, rails. Rail transport is one of the two primary means of ...

Cordesville

swing bridge A swing bridge (or swing span bridge) is a movable bridge that can be rotated horizontally around a vertical axis. It has as its primary structural support a vertical locating pin and support ring, usually at or near to its center of gravit ...

, upstream signs = , downstream = Cooper River Bridge (1929–2005) , downstream signs = Former US 17

Continuous truss bridges in the United States Holt Bridges in North Charleston, South Carolina Bridges completed in 1992 Road bridges in South Carolina Interstate 26 Bridges on the Interstate Highway System Warren truss bridges in the United States

See also

References