The Evergreen Water and Sewer District wants to move the boundary of its service area in order to serve potential new developments and grow its customer base. But the move would require approval from the city of Kalispell, which treats the district's wastewater and doesn't want to encourage urban sprawl in rural areas outside city limits.

The district is proposing what it calls a "zero-net swap," offering to remove about 108 acres from its roughly 8-square-mile service area so it can expand elsewhere. Cindy Murray, the district's general manager, said both the city and the Evergreen district can take advantage of the Flathead Valley's population boom.

"It's not a zero-sum game," Murray said. "Growth in Evergreen is not going to reduce growth in Kalispell or vice versa."

Evergreen is an unincorporated area, meaning it doesn't have a municipal government. Most of the community's water and sewer services are instead provided by the Evergreen Water and Sewer District, which doesn't have its own wastewater treatment facility.

Under an agreement adopted in 2015, the district can pump up to 805,000 gallons of wastewater per day into Kalispell's treatment facility along Airport Road — about 15% of the plant's capacity.

The agreement also means the Kalispell City Council must approve any expansions of the district's service area. The council approved an amendment that gave the district more wastewater treatment capacity in 2019, but city officials have said they won't allow service area expansions or provide additional treatment capacity moving forward.

"It's challenging because we did an amendment in 2019, and that was basically going to be the final amendment," Kalispell City Manager Doug Russell said.

"Any time you facilitate growth outside of your municipal limits, that decreases the demand inside," Russell said. "And the council has worked really hard to facilitate that growth inside city limits. That's where you want that smart growth to be."

BECAUSE AN expansion of the service area is off the table, the district wants to remove a 108-acre swath and then work with developers to push the boundary outward in other locations. Jack Fallon, the district's board president, first pitched the idea to the Kalispell City Council during a public meeting on June 7.

The area proposed for removal is bound by Waggener Way at the east, a small stretch of Reserve Drive at the south, and several bends of the Whitefish River toward the north and west. The district has dubbed the area the "thalweg" — an archaic legal term that refers to the centerline of a river.

The thalweg encompasses about 27 parcels that were added to the service area in 2016 when one neighboring property owner requested to hook up to the district's sewer system. But Murray, the general manager, said the other residents of the area have no need for the district's services.

"The people who live there have septic tanks, and they have their own sewer arrangements. No municipal or sewer district will serve that area," Murray said.

The district currently pumps significantly less than 805,000 gallons per day to Kalispell's wastewater treatment plant — the maximum allowed — and says it could serve roughly 1,100 more single-family homes before hitting that threshold.

MURRAY NOTED some developers have installed septic tanks just outside the district's service area, which, if not maintained properly, could contaminate groundwater and the Flathead River. The "swap" proposal, she said, could instead supply some new developments with a sewer system, a safer alternative.

Murray emphasized the district doesn't yet know where it would recoup the 108 acres of service area, but one idea is to expand into a currently undeveloped area just north of the Trumbull Creek Crossing subdivision, which straddles Mountain View Drive north of East Reserve Drive.

Officials with the district and the city were scheduled to meet Monday to discuss the proposal, after which city staff could issue a recommendation to the Kalispell City Council. There's no fixed timeline for a decision on the proposal.

"We'll meet with them and see what's the best recommendation moving forward," said Russell, the city manager.

Assistant editor Chad Sokol may be reached at 406-758-4439 or csokol@dailyinterlake.com.