Columbia Falls is eyeing about $2.8 million in upgrades to its sewage treatment facility and accessory equipment in the next couple of years. The cost to average users, however, could be less than $1 per month.
The city is also going to upgrade its water system. Those upgrades are expected to cost about $1.5 million and would raise the base water rate about $2 per month.
Combined, the upgrades could run the average homeowner less than $3 a month in additional charges.
City leaders got a first look at a plan for the sewer upgrades from Craig Caprara of HDR engineering Monday night during a workshop.
The city’s sewage treatment plant is nearing its total capacity and will need an additional cell in its bioreactor to meet future demands and state regulations for discharge into the Flathead River.
In his analysis, Caprara estimated the city would see an annual growth rate of about 65 homes a year with a population of over 7,000 in 20 years.
That growth rate hasn’t happened yet, however. Last year the city added 20 homes. It’s running out of in-fill lots — there’s about 150 lots left, without expansion outside the current city limits.
Because the river is in nearly pristine condition, the city is held to a high standard by the Montana Department of Environmental Quality for discharge of nitrogen and phosphorous as well as metals.
The plant building itself is also in need of renovations — including paint and some remodeling. For example, the lab doubles as the breakroom, so staff are eating lunch in the same room as they test sewage samples.
There are also accessory needs. One lift station that was built in the 1970s needs to be replaced and the city’s sludge truck, which is used to haul sludge to the county landfill, needs to be replaced as well.
Right now the cheapest and easiest way to get rid of the sludge — the solids that are left over from the treatment process — is to take it to the landfill, but Caprara said that some communities are opting to compost it. Once properly treated, it’s inert and coveted by gardeners. Kalispell is moving toward composting its sludge, Caprara noted.
The upgrades would likely be paid through a combination of the city’s cash reserves in its sewer fund, a loan through the state revolving loan fund, and a modest fee hike. Under one scenario, a 75 cent increase in the base fee per “equivalent dwelling unit” would help pay for the upgrade. An EDU is equivalent to the sewage use of a typical residential home. Commercial users that use more sewage would pay more, based on their EDU usage.
The city will also explore its contract with Meadow Lake Resort. The resort accounts for about one-sixth of the sewage produced by the city, but it’s contract hasn’t been updated in years and the resort keeps growing, city leaders note.
The city will pay off the loan from the last upgrade in 2009 in 2020, just in time for another upgrade. Councilmembers took no action on the matter — the workshop was just informational.
On the plus side, the plant is designed to accommodate expansion, Caprara noted. In fact, 20 years down the line it could still house another new bioreactor facility.