SAN FRANCISCO (KRON) — A big-rig truck toppled on its side and snarled traffic just before 5 p.m. Tuesday on the Bay Bridge in San Francisco. The bridge reopened just after 8:30 p.m., California Highway Patrol confirmed.

CHP San Francisco issued a “major traffic alert” for eastbound drivers following the bridge crash near Treasure Island.

“I-80 e/b (San Francisco/Oakland Bay Bridge), just east of 1st Street on-ramp, a big rig has overturned and the four left e/b lanes are currently blocked. Expect major delays! Please use alternate routes and avoid area if possible!” the CHP wrote on Twitter.

All trucks were being asked to exit Interstate-80 eastbound at Fourth Street. “Please do not attempt to cross the San Francisco/Oakland Bay Bridge at this time. There is not sufficient clearance for any trucks to pass the overturned truck and it will only create further congestion,” the CHP told truck drivers.

A big-rig truck crashed on the Bay Bridge on March 21, 2023 during windy weather. (Image courtesy Oren Kroll-Zeldin)

CHP Officer Mark Andrews told KRON4 that traffic will be heavily impacted on the Bay Bridge eastbound for several hours. “All traffic in the area is at a complete stop,” Andrews said.

As of 5:05 p.m., CHP officers still had not been able to reach the crash scene because the bridge was clogged with too many cars.

The big-rig driver likely lost control of the truck because of high wind gusts blowing through the bridge’s lower deck. “The wind may have been a contributing factor to this truck overturning,” Andrews said.

Caltrans District 4 officials urged drivers to use a detour by driving over the Golden Gate Bridge. “Motorists are encouraged to take U.S. 101 Golden Gate Bridge and State Route 92 for detour,” Caltrans wrote.

(Image courtesy CHP San Francisco)

At 5:39 p.m. the CHP said the far left and right lanes were briefly reopened, however, all lanes will be closed again once emergency vehicle arrive to upright the overturned truck.

As of 6:25 p.m., two eastbound lanes of the bridge were open and the first tow truck arrived on the scene, according to the CHP. “Emergency crews are working hard to clear the lanes and expedite traffic flow,” the CHP tweeted. “Further delays should be expected. Please be patient!”

Unusually strong wind gusts blew into San Francisco and created havoc throughout Tuesday afternoon and evening. Trees fell across several city streets. Three people were injured when trees landed on top of them on Post and Polk streets. A fourth victim suffered moderate injuries from being struck by a tree on Hyde and Ellis streets.

San Francisco Department of Emergency Management executive director Mary Carroll wrote on Twitter at 5 p.m., “Please use 911 for life safety calls only. 911 is being inundated with storm calls … and it is causing long delays for pending calls. Use 311 for storm related calls, and save 911 for when life is at risk right now.”

Wind gusts whipped up big waves in the bay and the Golden Gate Ferry suspended all service due to weather.