Baton Rouge, La. ? Travis Morace has been running boats on the Mississippi for two decades, witnessing all of the mighty river’s many moods. He’s seen it calm and smooth as a newly paved road and endured jarring rides filled with treacherous twists and bumps.

But even experienced river pilots have never seen anything like the roiling current now racing to the Gulf of Mexico. Since spring floods pushed the Mississippi to historic heights, America’s busiest inland waterway has become one of its most challenging to navigate.

“If you’re not scared of it, you should be, because it has a lot of ways of hurting you,” Morace said this week as he slowly nudged his tugboat, the Bettye M. Jenkins, along the river bank near Vidalia, La.

The high water brings with it a host of hazards. Debris is everywhere, and the unusually swift current makes it difficult for pilots to go upstream. Good luck stopping if you’re headed downstream. For those who make their living on the water, the river is a respected adversary in the best of times. Now it just plain frightens them.

On Friday, the Mississippi at Vidalia looked more like a stormy ocean than a river. Whitecaps frothed under the bridge that connects the city to Natchez, Miss., and whirlpools churned across the channel.

In many places, obstacles were hiding just beneath the surface. Some trees in Natchez were nearly submerged. A basketball hoop protruded about 2 feet above the water at a flooded-out court.

The current was filled with flotsam of every sort, including whole trees and long, green ribbons of vegetation. A nearby alligator struggled against the water’s pull, finally finding refuge on the porch of a building partly concealed by the rising water.

The high water and rapid current caused at least two barges to break loose from a towboat Friday and hit a bridge. Three barges of corn sank, the towboat’s owner said. No one was hurt.

The barges went down near Baton Rouge, prompting the Coast Guard to close a five-mile stretch of the river. Officials did not know when it would reopen.

“You ask me, they should close it down altogether,” said Jerry Batson, captain of the tug Gladys Batson. “It’s awful risky for any vessel.”