The hole was spotted around 5:20 a.m. just west of the toll plaza. It was about a foot wide and 4-6 inches deep, the CHP reported.
The hole appears to have been caused by a problem with a joint on the bridge's deck, and not by wear and tear from cars, Caltrans spokesman Bob Haus said.
Caltrans crews began pouring concrete to fill the hole at about 8:15 a.m. The lane reopened around 9:25 a.m., according to the CHP.