MIDDLETOWN — Town Council members unanimously decided Monday to seek proposals for engineering designs for a replacement wastewater treatment plant that will cost about $4.8 million.

Keith Lane, an engineer with Peed & Bortz, LLC, recommended the town would be best served by choosing the most extensive upgrade of its wastewater treatment plant.

“Option three is the only option that meets all of the needs (of the town),” Lane said.

Council members decided to follow Lane’s advice. This option would remove the bio-wheels and replace them with a modern system as well as construct a new larger basin for increased capacity. This option provides the highest potential for increased treatment performance and future capacity increase if needed.

After the special meeting, Vice Mayor Jeff Pennington said the upgrades are necessary.

“It’s a long-term investment in the town,” he said.

In January, Lane had given the town another less expensive option that he felt could work for them.

On Monday night, Lane said that as he continued to research that option he has grown less optimistic that it would work for the town. The town would probably soon need to have another significant upgrade done to the plant, Lane said.

Monday night’s decision means that town administrators will now be able to move forward with how to finance the project using a zero percent interest loan from the Virginia revolving fund.

Work on the treatment plant should take about two years to complete.

In January, town administrators and council members heard how bad conditions at the wastewater treatment plant are.

Lane told them the most pressing issue is the bio-wheels, which are at significant risk of failing. He told them it was a matter of when and not if they will fail.

One of the bio-wheels has already failed with the other five appearing to be getting ready to fall apart, he told them.

Town employees performed makeshift repairs on the failed bio-wheel that allows it to be used for a while, buying the town time to implement the upgrades, as previously discussed in a town meeting.

The bio-wheels are large rotating drums where attached microorganisms are grown to consume pollutants and treat wastewater. They work as the main biological treatment portion of the plant, Lane explained.

Lane has previously identified other problems with the plant including the need to increase the plant’s 400,000 gallon-capacity. The town, he said, experiences monthly peaks of 350,000.

Lane has previously said the town has to consider future growth, like The Village of Middletown, a development of 180 units under construction on about 60 acres of land near the Lord Fairfax Community College, and the demand it would place on the plant.

The town’s current wastewater treatment plant would also need to be upgraded to handle potential regulatory changes, including a pending change expected to occur to ammonia-nitrogen levels, Lane said.

– Contact Melissa Topey at mtopey@nvdaily.com