Tuesday, May 17, 2011

The Great Flood of 2011 (Part X)



Helicopter efforts to plug sand boil aborted Monday
By Vershal Hogan
Published 12:26am Tuesday, May 17, 2011

NATCHEZ — More than 2 million cubic feet of water per second are flowing through the Mississippi River at its Natchez pass, and today it is expected to stand at — and then exceed — 61.7 feet.

And Monday, that much water meant the Miss-Lou cities on both sides of the river had to up their flood fights.

In Vidalia, one of the temporary levees made of Hesco Bastion baskets on the riverfront filled with water after a sand boil erupted from the ground Sunday night. The boil originated in the parking area near the front of the convention center.

Ben Hillyer | The Natchez Democrat — Inmates from the Concordia Parish Correctional facility load sandbags onto the temporary levees outside the Vidalia Conference and Convention Center.

The boil started to form at 5:30 p.m. Sunday, and inmate crews have worked around the clock to sandbag around the convention center, Vidalia Mayor Hyram Copeland said.

“The Hesco boxes are working fine,” Copeland said. “You are gong to have some areas where the river is going to find a way in — in this case we think it was maybe an old drain left over by a construction crew — that will let that water come in and create a vacuum.”

The city attempted Monday to plug the boil with several extra-large sandbags flown in by helicopter.

Those efforts had to be aborted, however, because the helicopters caused too much turbulence against the Hesco boxes, Copeland said.

The mayor said the plugging operation would be attempted again today using a barge loaded with the large sandbags and a track hoe.

The water within the temporary retaining walls would need to rise another foot before it enters the convention center, and Copeland said pumps are being used to keep the water at a certain level to equalize pressure on the walls until the boil is plugged.

Copeland said such issues on the riverfront — which has been largely inundated by the record-high river — are expected.

Ben Hillyer | The Natchez Democrat — A helicopter is guided in place to drop a large sandbag into the water to plug up a sand boil that formed near the Vidalia Conference and Convention Center.

He also said seeing the water on the riverfront should not create panic.

“This (boil) has nothing to do with the mainline levee,” Copeland said. “Our mainline levees are in excellent condition.”

The U.S. Coast Guard closed down traffic on a 15-mile strecth of the Mississippi River near Natchez — from mile marker 350 to mile marker 365. This has been done to protect ships and flood control structures during flooding at record levels.

Closing the river near Natchez cuts off the waterway. Two vessels are waiting to move northbound and one vessel is waiting to move southbound, the Coast Guard said in a press release Monday. The press release does not mention when the river will be reopened.

At Natchez Under-the-Hill, an operation to place 350 feet of riprap downstream from the Silver Street boat ramp began.

The entire process will take 150 tons of size 200 stone, Natchez City Engineer David Gardner said.

The decision to place the riprap on the Natchez riverfront came after the completion of a sandbagging operation meant to stem sloughing issues that became evident Sunday, Gardner said.

“Before we did our sandbagging operation down there, I contacted the (U.S. Army) Corps of Engineers about the sloughing we were having,” he said.

“I got some phone calls from them, that they were bringing a team down to look at it — they were very prompt. They reviewed it and located some rock.”

Taylor Aswell | The Natchez Democrat — Soldier put together the cable sthat will be used to lift the huge sandbags by helicopter over to the Vidalia Conference and Convention Center.

The upper part of the sandbagged area does not have any revetment or other protection from the river, and Gardner said the riprap should protect it when the water rises to that level.

U.S. Army Corps of Engineers Mississippi Valley Division Commander Maj. Gen. Michael Walsh was on the scene Monday afternoon, and he said he expects to see another two feet of water on Natchez Under-the-Hill.

Across the Mississippi River Valley levee system, the Corps is seeing conditions it has never seen before, Walsh said.

Expected to crest at 63 feet May 21, Walsh said he does not foresee the river overtopping the mainline levees.

Instead, the biggest concern for the corps is under seepage, and he said local levee districts are patrolling to ensure the high volume of water does not undermine the levees.

“The pressure (on the levees) is just tremendous from any perspective,” Walsh said. “It is going to be on these (levee) systems for a long time.

“We just have to make sure we stay vigilant. A lot of people are getting flood fatigue.”

While Walsh said he did not expect to see the mainline levees overtopped, part of the reason the expected crest at Natchez was lowered by a foot Sunday was because the river overtopped an abandoned levee at Wilson’s Point near the Arkansas border, filling in a backflow area.

Mississippi Third District Congressman Gregg Harper also visited the area Monday, meeting with Natchez and Adams County officials to discuss the flood and flood response, and he said anything he or his office could do they would.

“As bad as its been, we’re cautiously optimistic,” Harper said. “It looks like everybody’s’ holding, and I wanted to thank (everyone) for the great job everybody has been doing.”

In other flood related news, a spokesperson for the Federal Emergency Management Agency announced that FEMA representatives would be in the Woodville area Thursday and Friday.

Ben Hillyer | The Natchez Democrat — The helicopter is given the sign to raise up from the levee to carry a large bag of sand over to the Vidalia Conference and Convention Center

“They will be handing out information to start the registration process for FEMA funds,” Spokeswoman Robin Smith said.

“This is for anybody who has been affected by the flood.”

The FEMA representatives will be at the Sportsman’s Stop on Mississippi 24 at Lake Mary Road from 10 a.m. to 2 p.m. both days.

FEMA can also be contacted at 1-800-621-3362.

— Emily Lane contributed to this story.


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