The Board of Mayor and Aldermen could learn the cost of replacing a damaged primary clarifier at the city’s wastewater treatment plant Tuesday.

The board is expected to open bids on the project when it meets Tuesday morning at the City Hall Annex. Preliminary estimates indicate the project will cost about $2.7 million.

The board put $1.3 million toward the project in the city’s fiscal 2017 budget, with the balance of the cost coming from $139,736 remaining from an original grant to repair the clarifier, a $600,000 Mississippi Development Authority grant for the project, and an additional estimated $187,000 for MDA.

The clarifier was damaged in February, when water from an unknown source cut its way under the clarifier at the wastewater treatment plant on Rifle Range Road and forced its way up, lifting the clarifier off its pilings and out of the ground, and bursting several pipes under the concrete basin.

The clarifier is one of two at the treatment plant and is part of the wastewater treatment process. Each clarifier is 100 feet in diameter and 20 feet deep. The damaged unit was shut down, and the plant has been operating with one clarifier.

Public works director Garnet Van Norman told the board at the time the incident occurred Feb. 12 during repairs on the equipment.

“We’re not sure where the water came from,” he said, adding city sewer department crews had to breach a levee around the clarifier to relieve pressure on it. He said wastewater from one of the ruptured pipes was pumped back through the plant.

In another matter, the board will open bids to replace the roof on City Hall. The project is part of a series of improvements and upgrades to the 112-year-old building. The city advertised for bids for the roof early in 2016, but received none, forcing city officials to re-bid the project.

The board allocated $375,000 in the $9.2 million capital improvements budget for exterior work to City Hall.