The Springfield City Council approved the purchase of filters for the wastewater treatment plant upgrades Monday.

City Manager Brett Bennett explained the difference in the two types of filters the council had to choose from.

“There is about a $30,000 difference from one filter to the next in the cost of the filter itself,” Bennett said. “Then there’s an additional cost in instillation.”

He said the more expensive filter will cost approximately $15,000 more to install. Bennett said the total difference in cost would be between $45,000 and $50,000.

Council member Kenny Usher said the engineer recommended the more expensive filter for the project. He said he went to the Rincon plant and spoke with the person about their filter, the Aqua Aerobic filtration system, which is the more expensive filter.

Usher said the filters are designed in opposite manners, and the engineer did not know how well the design of the expansions would work with the other system.

“Simply put, one filters from the inside out, and one filters from the outside in,” Bennett said. “In other words, you’ve got this center tube. All the dirty water comes into the center, forcing its way through the filters out into this open area where the clean water is in the tank. The other one, the dirty water will come into the tank and be sucked into the filter and come out clean.

“The concern is if a big glob of grease, sludge anything comes in from the inside and clogs up, how do you see what the problem is,” he said.

Bennett said if the dirty water were in a tank it would be easier to see a clog without having to dismantle the filter.

Usher said one of the questions asked by EMC Engineering was about clogs, and he was more comfortable with the solution given by Aqua Aerobic.

Council member Troy Allen said he liked that the surrounding areas were on the Aqua Aerobic system.

“We hired them for a reason,” Allen said of the engineers and his feeling to follow their recommendation.

Bennett said there is something to be said that everybody is using it because if a problem arises, there are plenty of people around to troubleshoot.

The members approved the purchase of the Aqua Aerobic system for $315,000.