Authorities have given a regional commission the go-ahead to drill test wells around downtown Baton Rouge in the region's ongoing fight to keep saltwater away from supplies of water used for drinking and industry.

Baton Rouge lies atop a geological fault that runs roughly along Interstate 10. South of the fault, the aquifer is salty, and saltwater has been leaching across the fault line into the freshwater aquifer for decades. Scavenger wells intercept saltwater and inject it deep underground or pipe it out.

The Baton Rouge Water Company operates a scavenger well near its Lula Avenue pump station and deposits the saltwater into the Mississippi River, where it's diluted. Now the Capital Area Groundwater Commission wants to dig its own scavenger.

The commission's board agreed to engage landowners to purchase property for a test well during a special meeting Tuesday morning. Several test wells will be dug to explore the aquifer salinity and determine where best to place a new scavenger well, said commission executive director Anthony Duplechin.

They are considering land within a few blocks of Interstate 10 between the Interstate 110 split and the Mississippi River. Duplechin declined to discuss the budget to purchase land so as not to weaken the commission's bargaining position, but the cost to install a 2,400-feet-deep test well will run $200,000 and $250,000, he said.

On the surface, the well will be no larger than a ten feet by ten feet concrete pad with a single pipe sticking out of the ground.

Commission members and observers have discussed at length whether scavenger wells are enough to combat the creeping saltwater.

Some have wondered whether to further limit industrial pumping or out-of-parish sales, such as to Ascension. The Water Company has purchased land on the Mississippi in case it ever needs to draw drinking water from the river in the future.

In June, the commission agreed to hire the Water Institute to study the matter and make recommendations.

Groundwater commission hires Water Institute to brainstorm aquifer protection, mulls fee increases

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