A detailed assessment of Meridian’s 67 wastewater pump stations is moving forward after the City Council signed off on the project in its meeting Tuesday.

Pump stations are installed at key areas along the city’s network of sewer pipes to push wastewater toward the city’s two wastewater treatment plants, and an assessment of the stations is a required component of the federal consent decree.

Jason Gault, of Kimley Horn, an engineering firm contracted with the city to manage projects involving the city’s wastewater infrastructure, told the council in a recent work session that the assessment will be far more in depth than anything the city has previously done. Physical inspections at each of the pump stations will be conducted, he said, and ideal flow rates — how much water moves through the station and how fast — will be calculated and compared to how the stations are currently performing.

The assessment, which will cost the city $456,000, will also include needed repairs and upgrades for the pump stations, as well as a prioritized list to help the city know what projects it should tackle first, Gault said.

Councilman Dwayne Davis said he was under the impression the city already has someone tasked with monitoring and maintaining pump stations. Why, he asked, should the city pay Kimley Horn to do work it is already paying someone else to do.

While the city does indeed have someone responsible for maintaining the wastewater pump stations, they are not equipped to take on the workload the assessment will require, Gault said. In making the assessment, he said, engineers will need to design all 67 pump stations and calculate critical response time, or the time between a critical alert at a pump station and a sanitary sewer overflow, the prevention of which is the driving goal behind the entire consent decree.

“You don’t have anyone with the current resources, workload who can do what’s required under this task order,” he said.

Waggoner Engineering’s David Ruhl, who helps oversee work related to the consent decree, said engineers will also be looking at where the city’s pump stations are located and whether all 67 are truly needed. The stations have been installed in a piecemeal fashion as the city grew, he said, and there could be potential cost savings if some stations can be combined or eliminated.

Pump stations are not cheap, Gault said, with the city’s smallest estimated at $500,000. The total cost to make all needed repairs and upgrades to the pump stations, he said, is estimated at $20-$30 million. The work, however, will not have to be done all at once, and the city will be able to chip away at it throughout the life of the consent decree.

Also on Tuesday, the City Council awarded a project to make improvements at the east wastewater treatment plant to Hemphill Construction for a total cost of $1,076,500.

James Lawson, with Neel-Schaffer Inc., an engineering firm overseeing work on the city’s two wastewater treatment plants, said the construction project is needed to bring more of the city’s wastewater to the east plant.

While smaller than the south plant, the east wastewater treatment plant is underutilized and has the capacity to treat more water than it currently receives. Taking advantage of that capacity will take some of the load off of the south plant, which currently handles the majority of the city’s wastewater, Lawson said.

Council members also voted to approve the purchase of a new influent coarse bar screen at the south wastewater treatment plant in Tuesday’s meeting at a cost of $279,407.17. The screen, Lawson said, filters out large debris in the wastewater arriving at the plant and prevents it from moving further into the treatment system, where it could potentially damage equipment.

Ruhl said the screen isn’t something the city can do without and must be replaced. Should debris get through, he said, the cost of the damage would be in the millions.