Bridge Collapse and the Duty to Warn

Author: Joshua B. Kardon, S.E. 
University of California, Berkeley

This case is an excerpt from "The Structural Engineer's Standard of Care."

Another duty of an engineer is the duty to warn. California Attorney General's Opinion Number 85-208 (1985) (Acret, 1991), states that a registered engineer hired to investigate the integrity of a building has a duty to warn the building's occupants if the engineer determines they face an imminent risk of serious injury due to a hazard the engineer observes. The Opinion requires the engineer to warn the occupants even though the building owner client of the engineer requires confidentiality on the part of the engineer.

The extent to which the duty to warn extends varies with location and circumstance, and the standard of care in one locality may not be the standard of care in another. The following case study is an example of this fact.

A 77-year old county-owned suspension bridge for pedestrian traffic, nicknamed Swinging Bridge, collapsed into the Little Red River in Arkansas in 1989 ("Appeals ...", 1996). Forty people were on the bridge at the time, engaged in the apparently popular activity of forcing the bridge to swing from side to side. The bridge collapsed, five people were killed and dozens were injured.

In 1982, seven years prior to the collapse, an engineering study evaluated and analyzed the bridge, and came to the opinion that the bridge was sound, and that it could provide adequate service for as long as an additional century. The engineer recommended further study be carried out, and although the bridge cables were free of rust, he recommended a protective coating be applied. The County did not follow the engineer's recommendations.

The victims and their relatives sued the County, charging it with failure to warn of the hazard presented by the bridge. The court ruled against the plaintiffs, stating, "Mere knowledge of danger to the individual does not create an affirmative duty to protect." The pedestrians caused the collapse and the County had nothing to do with it. The court apparently decided the defendants did not have to warn anyone, and the plaintiffs had to bear the consequences of their actions themselves.

This finding may not have been the conclusion of a court in a different jurisdiction, one where juries are more sympathetic to plaintiffs. If it were known the bridge could be damaged by being forced to swing back and forth, or if that fact should have been known, and if it were known that pedestrians regularly engaged in such activity, a more sympathetic court may have found the engineer who evaluated Swinging Bridge negligent in his failure to warn of the dangers. This tragedy could certainly have been prevented.