The Kalispell City Council confronted a multi-million-dollar unanticipated sewer infrastructure expenditure during a work session Monday.

Kalispell Public Works Director Susie Turner warned the city’s fermenter tank, which apparently has fallen into disrepair more rapidly than anyone expected, could cost up to $6 million to be totally reconstructed.

Public Works will start an in-depth assessment in August to determine whether such a comprehensive overhaul will be necessary for the facility.

A less intensive repair, if such an approach is deemed adequate, would come in somewhere between $1.2 million and $2 million.

“I did not anticipate the condition of the fermenter to be in such disrepair,” Turner told the council Monday evening.

She said the tank, completed in 2009, typically would be expected to last at least another decade before needing such extensive fixes. But for reasons Turner said she couldn’t understand, outdated practices used when the fermenter was first built have led to the facility’s rapid decay.

When the tank was constructed, between 2007 and 2009, the protective coating on the walls was only applied up to two feet above the ground. That ultimately left much of the structure exposed to corrosive chemicals, possibly compromising the structural integrity of the tank.

It will take a more thorough assessment for Public Works to determine the full extent of the damage.

That assessment will help the city decide whether it will be necessary to totally reconstruct the tank or simply rehab the areas of high concern.

Turner stressed the necessity of investing in the rehabilitation process, no matter how extensive it becomes. She reiterated the decaying fermenter tank is “one of the most critical components of the treatment process.”

The Kalispell City Council does not make formal decisions during work sessions.

IN OTHER discussion, the council went over another sewer presentation from the Public Works Department, in this case pertaining to stormwater regulations.

As Environmental Specialist Casey Lewis explained in her presentation, the Montana Department of Environmental Quality sets standards for sewer system permits across Montana municipalities.

Under Kalispell’s current five-year permit, the city is required to establish an Action Plan to control Total Maximum Daily Loads of stormwater being expelled into nearby water bodies, especially those designated as “impaired.” Around Kalispell, four bodies of water are considered impaired because they don’t meet the state’s water quality standards: the Whitefish and Stillwater rivers, and Ashley and Spring creeks.

Fortunately, Kalispell’s existing approach to minimizing pollutant output seems like it’s already doing a more than adequate job at meeting the standards of the permit. Lewis said the city’s use of both structural interventions and non-structural practices, such as street sweeping and leaf collection, keep the output levels low throughout Kalispell city limits.

In fact, Kalispell’s take on water pollutant output seems to be so effective, council member Sid Daoud asked if the city might be “doing too much” to keep the chemicals to a minimum.

“What I’m really after is the bang for the buck,” he explained, wondering whether Kalispell’s comprehensive efforts might exceed the necessary requirements.

Ultimately, others at the work session, including Mayor Mark Johnson, City Manager Doug Russell and Public Works Director Susie Turner, said they felt more comfortable exceeding minimum requirements rather than merely meeting those official standards.

Reporter Bret Anne Serbin may be reached at 758-4459 or bserbin@dailyinterlake.com.