TRAVERSE CITY — Aging sewer mains and parts of Traverse City Regional Wastewater Treatment Plant could get an upgrade.
City commissioners have unanimously approved a list of seven projects, totaling an estimated $26,807,000. Municipal Utilities Director Art Krueger said the city will ask to borrow the money for those projects from the Clean Water State Revolving Fund.
If state lenders approve, the city would seek bids to design and construct the projects, each of which would need commissioners’ approval before they could begin, according to Krueger.
“So we’re not committing to do all these projects in this plan, we’re just making them available to finance if we get the funding, and the funding process through the state of Michigan is quite competitive,” he said.
The single-costliest of the seven projects would build a new lift station on East Front Street to pump sewage to the treatment plant, while upgrading the existing, 1930s-built lift station for $5.93 million.
Krueger said after the meeting that the new station would be parallel to the existing one, and the project would also include upgrading the sewage force main that transports much of the city’s wastewater to 20 inches in diameter, up from 16.
Fans of the architecturally distinct lift station, fear not: plans are to leave it in place, just as a redundant lift station, Krueger said.
“In fact, we’re working on it right now, we’re restoring a lot of the exterior under contract with a restoration company,” he said.
One project would give Jacobs more chances to work on the membrane trains at the heart of the plant. Enclosing the membrane bioreactor for $4.14 million means plant operators could work on those membrane trains in a heated environment, Krueger said. Those trains, which consist of thousands of strands of tiny perforated tubes that filter pathogens and sediment out of partially treated sewage, can’t be allowed to freeze.
“So if we were able to have a heated enclosure, then we could perform maintenance year-round,” he said.
Two other treatment plant upgrades would overhaul an aging anaerobic digester that turns sludge settled out from wastewater into biosolids, at $4.48 million, and improve the plant’s odor control system for $1.73 million.
Krueger said he’ll ask commissioners to approve a contract at their May 4 meeting for an odor source study to better determine where bad smells are coming from at the plant, and how to curb them.
Other projects on the list include repairing and rehabbing sewer mains and access holes for $3,963,000, and replacing part of the collection system and force mains for the city’s east side for $5.69 million.
Submissions for the state loan fund were due Friday, and the city should know by August if its application is approved, Krueger said. Money would be available for the projects in October, and the first round of projects are planned for 2027.
The loans have a 20-year repayment period, and current interest rates are 3%, according to Urquhart.
The five-year plan is the second one the city submitted for the state-administered, federally funded loan program, according to Krueger. For the first, approved in 2021, the city relocated a sewer main along the Boardman-Ottaway River between Union and Cass streets. It’s also in the midst of a roughly $40-million overhaul of the wastewater treatment plant’s first and last treatment stages.
Borrowed money must be repaid, and for these projects city sewer customers would be footing the bill. Krueger said an estimate included in the project list of $9.42 per month for each residential user is just a raw figure and doesn’t reflect an actual increase. The city formulates rate increases with cash flow predictions as part of its annual budgeting process.