BUTTE LAROSE, La. (AP) — Cajun-country towns in the path of Mississippi River floodwaters were all but deserted Monday as residents heeded warnings to seek higher ground after a major floodgate was opened for the first time in four decades.

Sheriff’s deputies and National Guardsmen have been showing up at residents’ front doors and telling them to leave since the Morganza spillway was opened Saturday to divert the bulging Mississippi’s water away from the heavily populated cities of Baton Rouge and New Orleans.

On Monday, 75-year-old Leif Montin watched a truck tow away a storage pod containing most of the furniture he and his wife have in their home in Butte Larose, a community emptied by residents fleeing the rising waters.

“I guess you guys are ready to get out of here,” the driver said to Montin.

“Yep. Pretty much,” responded Montin, who plans to spend a few more nights in the house or a nearby camp before leaving town.

Meanwhile, President Barack Obama flew to Memphis, Tenn., on Monday and met with families affected when the river flooded there as well as local officials, first responders and volunteers.

Days ago, many of the towns in Cajun country bustled with activity as people filled sandbags and cleared out belongings. By Monday, areas were virtually empty as the water from the Mississippi River, swollen by snowmelt and heavy rains, slowly rolled across the Atchafalaya River basin. A hand-painted sign in front a deserted Butte Larose home said it all: “My slice of heaven force-flooded straight to hell. God help us all.”

The floodwaters could reach depths of 20 feet in the coming weeks, though levels were nowhere close to that yet in Butte Larose and nearby towns that lie about 50 miles downstream of the Morganza. Water hadn’t reached Montin’s home, but a canal behind it has been rising by about a foot a day since the Morganza was opened. He’s trying to remain optimistic that his house won’t take on too much damage.

“I’m keeping my fingers crossed,” he said.

Elsewhere, in an effort to keep a major shipping connection between the Gulf of Mexico and the Mississippi River open, the U.S. Army Corps of Engineers moved in a fifth dredge to dig sediment out of the Southwest Pass. A high river brings a huge amount of sediment and the dredges were being used to keep the 45-foot channel needed for deep-draft shipping.

Over the weekend, the Port of New Orleans said it had been told by the Coast Guard that shipping probably would continue largely unhindered on the lower Mississippi.

About 30 miles north of Butte Larose in the town of Melville, Mary Ryder, her fiance and her fiance’s father were loading up a trailer Sunday with as many belongings as they could fit to drive over the levee to stay with relatives on the other side of town. Ryder lives in a mandatory evacuation area, where water is starting to creep into backyards. They worried about what might happen if a broader evacuation is ordered.

“They say we have to leave town. We have nowhere to go,” she said. “What are we going to do? I have no idea. We need help up here.”

The spillway’s opening diverted water from the two major Louisiana cities — along with chemical plants and oil refineries along the Mississippi’s lower reaches — easing pressure on the levees there in the hope of avoiding potentially catastrophic floods.

That choice angers John Muse, who drove from Lafayette to Melville to help his 86-year-old father-in-law Clovis Cole move his belongs. He said officials seem to be paying more attention to the concerns of Baton Rouge and New Orleans than people who live in the basin.

“They hurt a lot of feelings by putting that water in here like they did,” he said. “What’s happening here, I’ll tell ya, it’s not fair.”

It will be at least a week before the Mississippi River crest arrives at the Morganza spillway, where officials opened two massive gates on Saturday and another two Sunday. There are 125 in all. The Mississippi has broken river-level records that had held since the 1920s in some places. The Morganza was last opened in 1973.

The Army Corps of Engineers has taken drastic steps to prevent flooding. Engineers blew up a levee in Missouri — inundating an estimated 200 square miles of farmland and damaging or destroying about 100 homes — to take the pressure off floodwalls protecting the town of Cairo, Ill., population 2,800.

The Morganza flooding is more controlled, however, and residents are warned each year that the spillway could be opened. A spillway at the 7,000-foot Bonnet Carre structure in Louisiana also has been opened.

It seemed animals didn’t want to be stuck anywhere: Deer, hogs and rabbits have started running from the water flowing near the floodgates, said Lt. Col. Joey Broussard of the Louisiana Department of Wildlife and Fisheries. An electronic sign on Interstate 10 warned of a possible animal exodus: “Wildlife crossing possible. Use caution,” it read.

Despite the mandatory evacuation order, Krotz Springs town clerk Suzanne Bellau said it was unlikely the sheriff’s office would force people to leave. For most, the worst part was wondering what may happen. National Guardsmen were building a second levee to bolster protection for the town.

“It’s the unknown, that’s the problem,” Bellau said. “Is it going to come into their homes or not? And the people who are leaving, what are they coming back to?”

Bernadine Turner, who lives in a mandatory evacuation zone near Krotz Springs, had been moving things out over the weekend and was still working on it Monday.

“They’re going to let us go and come until the water starts coming up,” the 49-year-old said. “We’re hoping it’s still a few days away.”

The bayou flowing through their backyard showed little signs of rising. But Turner said a heavy rainstorm is enough to drive water into their yard, so she was taking no chances.

“There’s no doubt it’s going to come up. We don’t have flood insurance and most people here don’t. Man, it would be hard to start all over,” she said.