When a four-inch crack was found in the main girder of the Green River Bridge on I-26, the North Carolina Department of Transportation devised an innovative rehabilitation plan that minimized construction cost and time. To repair North Carolina's tallest bridge - which extends 235 feet above the Green River near Saluda - the department used high-strength bolts that reduced the stress in the girder. Other retrofitting included removing the majority of the joints, using a new type of non-shrinking concrete (Type K), installing a new riding surface and protecting the steel girders from damaging de-icing salts. When the bridge was completed in 1968, it was one of the first times that high strength welded steel girder construction was used in North Carolina. Across the country, steel girder construction on bridges has caused problems. The crack was discovered during a routine inspection. After extensive testing and analysis, the steel was found to be of substandard quality.