In the early morning hours of September 15, 2001, four loaded barges crashed into one of the Queen Isabella Causeway's support columns traveling at 2/10ths of 1 mile per hour. Three 80-foot (24.4 m) sections of the bridge fell into the water, leaving a large gap in the roadway. The collapsed sections were just next to the highest point of the causeway, making it difficult for approaching drivers to notice. Eight people were killed as their cars fell 85 feet (26 m) into the water. Five vehicles were recovered from the water along with three survivors.
The collapse had a significant economic impact on the region since the Causeway is the only road connecting the island to the mainland. The bridge also carried electricity lines and fresh water to the island. State officials brought in ferries to temporarily carry cars across the Laguna Madre.
In addition to the three bridge sections that toppled in the original accident, two adjacent sections were also replaced due to structural damage. The Causeway was reopened on November 21, 2001. Several safety features were added to the structure. The support columns were reinforced, and a $12 million fiber optic driver warning system was installed. News and discussion of the collapse was mostly confined to local and regional sources due to the September 11, 2001 attacks four days before.