Those trying to get out of the city a day early ahead of this holiday weekend may be in for a little extra time on the Bay Bridge as the Yerba Buena Island exit is closed — causing a serious traffic backup. The Chronicle reports that a truck bed full of mud and sand was dumped, perhaps intentionally, around 4:45 a.m. on the roadway and that officials have yet to determine if the mixture contains hazardous chemicals.

The exit has been closed all day as a result.

The California Highway Patrol is on the hunt for whoever may have dumped the material, but that is little consolation to all the drivers stuck in traffic. According to CBS 5, charges could be filed against the truck driver for failing to properly secure the load.

Caltrans, of course, is working to clean up the mess with heavy machinery including front-end loaders.

Meanwhile, KRON 4 informs us that this morning the backup went all to San Bruno. If eastbound motorists want to get to Treasure Island, they now have to pass the island and double back. A quick check in Google Maps shows that things haven't improved that much since this morning.

Happy commuting!

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