OKLAHOMA CITY, Oklahoma - The Oklahoma Department of Transportation is just now able to assess how much damage they're dealing with after floodwater washed out highways.

State leaders say the damage is already in the millions and that number is only expected to grow. Oklahoma will get federal help, but there is lots of work to get done. 

"I haven't seen anything like it, it's historic floods," said Governor Kevin Stitt. 

All that rain is causing issues for roads across Oklahoma. Highway 62 in Muskogee County is one with the worst damage.

"A lot of our work will happen after the water levels begin to recede we already know we've lost shoulders off of our highways, said Oklahoma Transportation Secretary Tim Gatz.

Gatz estimates what he's calling "extreme damage" at $2 million. 

He expects that amount to rise with more rain in the forecast.

"We'll monitor those situations closely, one drop of rain that falls into the watershed now is a big deal," he said.

150 highways closed across the state since April. Gatz said one of the biggest concerns is driftwood they're trying to remove from the water before it ends up on bridges.

That could take up to two years.

"I was so happy the federal government was able to step in and declare some disaster areas," Stitt said. 

Governor Stitt spoke with President Trump over the phone last week.

Three Oklahoma counties have been approved for federal aid: Muskogee, Tulsa, and Wagoner. Stitt said Oklahoma will continue to stay strong.

"Oklahomans are just amazing, I think we've weathered this disaster very very well," he said. 

As of Monday, 17 roads were still closed. Governor Stitt said he's working to get more federal aid to other counties. He's asking storm victims to call 211 to report their damage.