Beginning next month, DeKalb and Cortland residents will pay just a little more each time they flush the toilet.

Michael Zima, DeKalb Sanitary District manager, said the sanitary district is increasing the cost of treating wastewater 25 cents for every 750 gallons treated. Currently, residents pay about $1.35 for every 750 gallons of wastewater they produce.

The quarterly bill arriving at homes and businesses in January will reflect the increase. The average family will only pay $2.50 more a month, Zima said.

The sanitary district, which last raised the rate in 1996, decided to increase its rate because of the growing costs of labor, utility, insurance, operation, maintenance and expenditures, Zima said.

“We are very cost-conscious,” Zima said. “We are not unnecessarily raising rates. Basically we’re saying we need to fund what we need to do.”

One unit of metered water is equivalent to 748 gallons. For a family using 30 units of metered water (22,440 gallons) per quarter, the increase will equal $7.50 per quarterly billing.

Zima said he expects the most affected users will be NIU, laundromats and businesses that produce a lot of wastewater.

Cathy Kalman, Cortland Estates manager, said the increase will affect their 96-unit apartment complex, 4100 Aspen Road.

“The cost is usually passed on [to the user],” Kalman said.

Greg W. Davis, controller at Mason Properties, 120 N. Annie Glidden Road, said he doesn’t anticipate apartment rents going up because of the user rate increase. However, Davis said the increase will affect only Mason Properties since it is paying the bill.

Zima said he anticipates the rates will continue to rise sometime in the future due to an increase in maintenance costs and rehabilitation of old infrastructure, treatment units at plant and sanitary sewers, improvements to wastewater treatment processes and EPA regulations.

The DeKalb Sanitary District, at 303 Hollister Ave., has decided that user rates will increase by 25 cents per 750-gallon unit treated.