As the city of Whitefish anticipates needing up to $20 million for a new sewage treatment plant over the next eight years, water and sewer rates are on track to increase again this year for city residents and businesses.

The Whitefish City Council will hold a public hearing Monday, Oct. 1, to consider the latest round of utility fee increases before voting on a resolution that bumps up rates.

Customers will see the biggest rate increase in sewer costs, which are proposed to jump nearly 14 percent, from $44.66 to $50.89 monthly for customers inside city limits with a 5/8-inch meter who use about 4,000 gallons of water and wastewater per month.

Monthly water costs will increase 0.73 percent, raising the average customer’s water bill by about 20 cents, from $41.08 to $41.38, according to a report by Whitefish Director of Public Works Craig Workman.

Customers with a landscape/irrigation meter with usage of 10,000 gallons per month would see a rate increase of close to 5 percent, from $42.80 to $44.90 per month.

Whitefish provides water service to about 3,250 residential customers and 320 commercial users within city limits, as well as 68 residential and seven commercial customers outside the city.

Sewer service is provided to 3,530 customers in the city and 106 customers outside city limits.

Five years ago the council adopted a resolution that stipulated water and sewer rates would be automatically adjusted on Oct. 1 of each year based on the Consumer Price Index. However, the completion of a comprehensive rate study typically is recommended every three to five years, or if a major change to utility operations or expenses are planned, Workman said. The city hired AE2S to complete a water and wastewater financial plan and rate structure study in 2015.

The proposed rate increases are based on AE2S’ cost-of-service analysis. A year ago the council approved rate increases in what are expected to be multi-year rate increases. The rate study recommended increasing water rates by 3.6 percent over the next five years, while sewer rates could jump as much as 95 percent over the next decade because of the new sewage treatment plan that is expected to be up and running in 2021.

If the council approves the rate increases they will become effective immediately.

The council meets at 7:10 p.m. at Whitefish City Hall.