Thatcher Lock and Dam is closed to navigation

The U.S. Army Corps of Engineers said Friday that the Thatcher Lock and Dam will be closed to all navigation due to high water levels. A notice sent out at approximately 2 p.m. Friday said navigation would close in the 12 hours following its release.

The release cited high water levels caused by heavy rain and a temporary dam structure’s inability to be lowered as reasons for the closure.

A poiree needle dam was installed at the Thatcher Lock and Dam in November after a leak, caused by a broken hinged crest gate, drained the Ouachita River to historically low levels last October. The poiree needle dam is designed to maintain the river’s water levels at least at 71 feet while the hinged crest gate is repaired.

“The poiree needle dam literally is temporary. It’s stakes and rods driven into the ground with a sheet of plastic. It’s not adjustable,” Robert Reynolds, a volunteer advisor to the Union County Water Conservation Board who previously served as the board’s president, said. “The permanent lock and dam is adjustable… but it failed, which led to the installation of the poiree needle system.”

According to the U.S. Army Corps of Engineers, the river, as of Friday afternoon, had risen to 80.75 feet and was expected to hit the 81 foot threshold to close down navigation as a safety precaution. Usually, the hinged crest gate would be able to be lowered to allow water to escape, but the poiree needle dam does not have that capability.

However, Union County industries that utilize water from the river shouldn’t be affected by the bar on navigation, Reynolds said.

“Barge traffic — which, there’s really not any — would not be allowed,” he explained. “Any impact on Union County is absolutely none.”

Recreational use of the waterway will also be closed, but Reynolds explained that the high water level would likely be enough of a deterrent on its own.

“People do use that lock and dam to get from below Thatcher to above it and vice versa,” he said. “I think that the high water levels that are out there are a deterrent to recreational usage. It’s dangerous — not only is the water deep, but it’s moving fast.”

A buoy line has been placed across the river to make the high water hazard visible to

boats, according to the U.S. Army Corps of Engineers. The agency expects water levels to decrease in the next three to five days, barring additional rainfall.

On Friday, the National Weather Service forecast high chances of rain in Calion, which is next to the Ouachita River, north of the Thatcher Lock and Dam, for Wednesday, March 30. The city was also under a flood warning Friday afternoon.

Water vessels are strongly urged to adhere to the closure until the waterway is formally reopened to navigation.

Pool levels at the Thatcher Lock and Dam are available at water. weather.gov/ahps2/hydrograph.php?wfo=lzk&gage=cala4.