(KRON) -- The southbound lanes of U.S. Highway 101 in Santa Clara County were closed Thursday morning after a gas spill caused by an overturned big rig, according to Caltrans. Maintenance crews shut down the roadway just before 5:30 a.m. after the crash spilled an estimated 600 to 700 gallons of ga soline onto the wet pavement near Dove Hill road and Hellyer Avenue. Hazmat teams are still on scene working to contain and clean up the spill. Bay Area storm updates: Tens of thousands without power Southbound traffic is being diverted at Yerba Buena Road. Crews are now preparing to shut down the entire highway to complete the cleanup. Caltrans said traffic impact is minimal because of light Christmas Day travel. There is no estimate for when the highway will reopen. ...read more read less