State battles erosion along I-10

New embankments to support road base

The southern side of eastbound Interstate 10 near the Cornerview Road overpass in Ascension Parish looked recently like an earthen flight of stairs, gradually rising up to the cars, pickups and 18-wheelers whizzing past at the top.

Workers, dump trucks and bulldozers have been removing the grass-covered earthen embankment alongside I-10 that once held the highway’s road base in place and are replacing it with better, more stable material, officials said.

Coastal Bridge Co. won a $1.68 million contract with the state Department of Transportation and Development to patch I-10’s concrete road surface between La. 73 to La. 22 and to repair I-10 embankments near Cornerview, officials said.

The concrete patching job is requiring intermittent nighttime lane closures, DOTD officials said.

DOTD spokeswoman Lauren Lee said the embankment repairs, which are expected to cost $761,000 under the contract, were needed because of “erosion issues.”

“The problem was all the material has slid down, and there was no support for the road base,” said Kelly Sills, owner and president of Coastal Bridge.

Comparing the replacement process with the interlocking nature of LEGO building blocks, Sills said his company is putting in, one at a time, 12-inch deep layers of dirt covered with a geo-textile fabric to better hold the new embankment in place.

The steps, or “benches,” left behind after the old embankment was removed help tie in the new material with the existing bed, Sills said.

DOTD’s Lee said the geo-textile fabric, which looks like giant sheets of black plastic, also will help channel water out of the embankment slope to minimize future erosion.

Sills said his company will be doing similar embankment work around the I-10/Cornerview overpass, on the north side of I-10 westbound, as well as on the north side of eastbound I-10 inside the median.

Sills said another section of embankment on westbound I-10 about 500 feet east of Cornerview also will be repaired.

Sills said his company has plans to order 93,000 square yards of fabric but noted the figure could change depending on what workers find when they starting digging out more embankment.

Sills said DOTD is being proactive and repairing the embankments before the road base was affected.

He said his company has done this type of project before, most recently along I-10 near La. 22 in Sorrento.

He said he hopes to finish the embankment project by the end of year depending on the weather.

He said he could not say how much dirt would be removed because it depends on what workers find.

Sills said his company is looking for the most cost-effective way to remove the old embankment dirt and will give it to people willing to truck it away.

He warned, however, that the dirt is a clay, organic mix not suitable for embankments under the state specifications, which, he says, have increased greatly in recent years.

“It’s not a high-quality material,” Sills said.