On June 24, 1970, two of the I-beams supporting the staging area on the Kittery side of the span gave way, plunging four workers 75 feet (23 m) to their deaths and leaving another seven injured.

[11] Since the bridge opened, there have been various instances of people jumping off the structure, many (but not all) of which have proved fatal—examples of such events, along with other incidents reported in area newspapers, follow in this section.

[12][13] The incident led to Maine and New Hampshire working to identify exact state boundaries on the bridge, in order to determine jurisdiction.

[12] On October 12, 1989, a New Hampshire contractor died of head injuries while working on the bridge; his employer was later fined by OSHA for safety violations.

[17] On May 5, 2022, a man experiencing a mental health crisis and threatening to jump off the bridge was successfully talked down by members of the Maine State Police following a two-hour dialogue.

[19][20] In the afternoon of October 27, 2024, a man who reportedly jumped from the bridge was rescued by New Hampshire Marine Patrol personnel, then transported to a local hospital.