GAINESVILLE (970 WFLA) -- A river pushed higher by Hurricane Irma's rains could spill over Interstate 75, closing the busy highway in North Florida and cutting off road access between Tampa and Atlanta, for evacuees returning home and trucks bringing supplies. 

The Florida Highway Patrol says the Santa Fe River, at the northern border of Alachua County, has risen 15 feet in 36 hours. 

Governor Rick Scott is monitoring the situation. He says they should know sometime Thursday if the crest will force authorities to close the road. 

"If (we do), it's going to be a pretty big detour", Scott says. 

From Tampa, drivers would get off at Ocala, cut over to U.S. 19, and then take that back to Interstate 10 and 75. Or they might take US 301 east to Jacksonville and cut back. 

Drivers going all the way to Georgia could stay on 19, which is a divided highway all the way to Albany, Georgia, then take the Florida-Georgia Parkway east to I-75. 

Any alternate route would likely add several hours to travel in and out of the Tampa Bay area. 

Scott says he's warned utility companies to warn them to get south of the Santa Fe as quickly as possible. He says he hopes any closure won't significantly impact recovery efforts.