The city is seeking a three percent sewer rate increase that would take effect in January.
Officials said it would add about 70 cents to the cost of an average residence using about 5,000 gallons of water per month.
The hike is on top of and separate from a whopping water quality fee increase that has already been approved. That fee deals with stormwater runoff.
The City Council plans to vote next Tuesday on the three percent increase.
It must be approved on second reading the following Tuesday.
Public works officials said the extra funds are needed to cover operational costs and system maintenance.
Jerry Stewart said the city has lost some income with the demise of some industries, including the Stowe Mills, and with the installation of much more efficient, water-saving toilets in homes and businesses.
Mr. Stewart said there are currently no plans to separate the remaining 70 miles of city sewers that are combined with stormwater runoff lines.
He said when the city sees an opportunity to separate those lines, it does - such as during the recent work at Warner Park and the earlier work along the Riverfront.
Mr. Stewart said it would cost $400 million to completely separate the sewer lines from stormwater lines.
He said the city a number of years ago chose to spend $40 million to build eight CSO facilities that store large amounts of stormwater during heavy rains, then release the water slowly later.
Mr. Stewart said the city at one point went nine years without a sewer rate increase, but has had a number of increases in recent years.
He said the bill to a residence using the minimum amount of water (2,000 gallons per month) would go up 28 cents.