Kacy Hanson, a 41-year-old transient man, had been released from a San Mateo health care facility two hours earlier when someone reported seeing him walking eastbound on the bridge toward the high-rise portion around 4:30 p.m., reported the CHP.
Two units and a supervisor reported to the scene and a staging area was established for additional emergency vehicles just west of the bridge at pier 1.
A negotiator from San Mateo Sheriff's Office was requested and all other personnel were directed to the staging area.
Hanson went outside the railing and interlocked his arms in the railing and gained foot support, according to the CHP.
At this point one of the three traffic lanes were closed and the traffic queue was contained to eastbound traffic that began at Foster City Boulevard half a mile west of the incident. The Coast Guard had an emergency boat placed at the base of the bridge.
The negotiator was able to have Hanson return inside the railing. He was then detained and placed in a patrol car.
He was taken for a 72-hour psychiatric hold pending additional criminal charges.
Normal traffic resumed at 6:30 p.m.