LIVINGSTON — The Livingston Parish Council voted Thursday night to sue Ascension Parish to stop the Laurel Ridge Levee extension project.

“In no way do I want to hurt Ascension Parish, but on the other hand, I want to do everything I can to protect the people in Livingston Parish,” Livingston Parish President Layton Ricks told the council.

The council voted unanimously to allow Ricks through Parish Legal Advisor Chris Moody to file for a preliminary injunction to stop the project. The vote came after at 20-minute executive session.

The lawsuit marks a major escalation in the feud between the parishes over the levee that has raised broader questions about what effect Ascension’s system of levees and pumps along the Amite River is having on drainage in lower Livingston and whether there ought to be regional oversight of flood control projects.

Ascension and the Pontchartrain Levee District are planning to build a 4.5-mile, $24 million extension to the Laurel Ridge Levee in the St. Amant and Lake areas. The project, which has been in discussion since the late 1970's, received a key permit earlier this year from the U.S. Army Corps of Engineers.

Since news of the permit was announced in February, Livingston leaders and residents in the southern part of the parish have raised concerns that the levee could make them more vulnerable to flooding during major storms. 

“We have enough water issues as it is. We don’t need anybody else dumping any water on us on top of what we have,” Ricks said Thursday night.

Moody said he still hopes Ascension will come to the table with Livingston to find a solution that works for both parishes.

“We don’t really want to pursue litigation against our sister parish,” Moody told the council. “I know you don’t either. But we feel like we have to get this (request for an injunction) in place. We would be happy to negotiate and talk to them, but it doesn’t seem like they’re stopping.”

Moody said he will ask for a judge to grant a preliminary injunction, and if the judge agrees the damage is irreparable, he or she could stop the project. It was not immediately clear Thursday in which court Livingston will sue.

Kyle Gautreau, Ascension Parish's communications director, said Thursday the parish does not comment on potential or pending litigation.

Ascension officials have downplayed Livingston’s concerns in the past, pointing to a study by GSA Consulting Engineers and GEC Inc. that says the project would cause at most 1.3 inches of additional flooding on lower Livingston.

But a second report from engineering firm HNTB, which was obtained by The Advocate through a public records request, suggests the impacts could be greater in combination with other levee improvements.

The study looked at the combined effect of extending the levee and raising it. The modeling shows the levee could put an additional half a foot of water on French Settlement and as much as 2.5 to 3.5 inches as far east as the Whitehall and Maurepas areas during a 100-year flood.

Only the levee extension project is permitted and funded at this time.

Both studies show the levee projects would lower water inside the protected area in Ascension by about 3 feet during the same flooding event.

Chad Bacas, an engineer with Forte and Tablada who reviewed the studies for Livingston Parish, noted both studies in his comments to the council Thursday. He acknowledged that they are “a little bit different” from one another, but he said both show an increase in flood levels along the Amite River.

Ascension Parish Interim Public Works Director William Daniel has said the two studies are "apples and oranges," because one considers the effect of the extension alone and the other considers the extension and levee raising together. He said the parish has asked the engineering firms to try to reconcile the differences between their reports.

Follow Caroline Grueskin on Twitter, @cgrueskin.