Drivers heading north for home this holiday weekend or driving to the University of Florida-Florida State football game may want to build in some extra commute time.

The right lane of a portion of northbound Interstate 75 in Marion County is shut down after a vehicle on County Road 329 near Reddick struck the highway overpass.

The crash caused major damage, and the Florida Department of Transportation doesn't know yet how long it will take to fix it.

“It appears two girders, about 61 feet long, have been damaged and compromised, and the replacement beams will need to be cast, cured and shipped before they can be put in place as part of the repair,” FDOT spokesman Steve Olson said.

The repairs could last for a number of weeks, although no established timeline is in place at the moment, he said.

A minimum of two lanes of I-75 should be open during all peak periods of traffic. FDOT has considered opening a third lane, but it's likely not to happen because of the extent of the damage to the beams and other factors, FDOT said.

The agency is currently selecting a team to make the permanent repairs necessary to fix the I-75 overpass.

If traffic significantly backs up on I-75, an alternative northbound route is to exit the interstate at State Road 326 closer to Ocala, take 326 to U.S. 441 and head north on that roadway until turning back west on West Highway 318 to get back on the interstate north of the damaged overpass. Or, if you're heading to Gainesville, take U.S. 441 all the way into town.