About 0745, on May 26, 2002, the towboat Robert Y. Love, pushing two empty asphalt tank barges, was traveling northbound on the McClellan-Kerr Arkansas River Navigation System, near Webbers Falls, Oklahoma. As the tow approached the Interstate 40 highway bridge at mile 360.3, it veered off course and rammed a pier 201 feet west of (outside) the navigation channel. The impact collapsed a 503-foot section of the bridge, which fell into the river and onto the barges below. According to witnesses, highway traffic continued to drive into the void in the bridge created by the collapsed spans. When traffic stopped, eight passenger vehicles and three truck tractor-semitrailer combinations had fallen into the river or onto the collapsed portions of the bridge. The accident resulted in 14 fatalities and 5 injuries and caused an estimated $30.1 million in damage to the bridge, including the operation of detours, and $276,000 in damage to the barges.
The National Transportation Safety Board determines that the probable cause of the Robert Y. Love's allision with the Interstate 40 highway bridge and its subsequent collapse was the captain's loss of consciousness, possibly as the result of an unforeseeable abnormal heart rhythm. Contributing to the loss of life was the inability of motorists to detect the collapsed bridge in time to stop their vehicles.
Major safety issues identified in this accident include:
- The captain's incapacitation and countermeasures for such an event;
- Bridge protection, including risk assessment; and
- Mitigation of loss of life, including motorist warning systems.
As a result of this accident, the National Transportation Safety Board makes recommendations to the U.S. Coast Guard, the Federal Highway Administration, and the American Association of State Highway and Transportation Officials.
As a result of this accident, the Safety Board makes the following safety recommendations:
To the U.S. Coast Guard:
Direct the U.S. Coast Guard Research and Development Center to evaluate the utility and effectiveness of wheelhouse alerter systems on inland towing vessels for preventing accidents. (M-04-3)
To the Federal Highway Administration:
Revise your sufficiency rating system, which prioritizes bridges for rehabilitation and replacement, to include the probability of extreme events, such as vessel impact. (H-04-29)
Develop an effective motorist warning system to stop motor vehicle traffic in the event of a partial or total bridge collapse. (H-04-30)
To the American Association of State Highway and Transportation Officials:
Once an effective motorist warning system has been developed, provide guidance to the States on its use. (H-04-31)
Previously Issued Recommendation Classified in This Report
Safety Recommendation H-94-9, previously issued to the American Association of State Highway and Transportation Officials, is reclassified from "Open-Acceptable Response" to "Closed-Superseded" by Safety Recommendation H-04-29.
In cooperation with the Federal Highway Administration, broaden the application of risk-assessment and management programs to existing highway bridges. Such programs should include, among other things, a formal assessment of the vulnerability of bridges to vessel collision and collapse.