AUBURN – Water users could face a 9 percent rate increase next year, according to Water Department officials.

The Auburn Water District has scheduled a public hearing on the proposed rate hike at 7 p.m. Oct. 24 in Auburn Hall. Superintendent Norm Lamie said district customers should begin receiving brochures on the proposed hike on Friday.

The new rate would increase quarterly costs for average customers from $39.12 per 2,000 cubic feet of water to $42.16. That’s 47 cents per day for 166 gallons, the average for a three-person household. The rate now comes out to about 43 cents per day for a three-person household.

The hike would pay for a new 24-inch water main into New Auburn as well as higher general operating costs. The new main will cross the Maine Central Railroad and the Little Androscoggin River east of the intersection of Washington and Markalyn streets. It would replace a 1890s-vintage 8-inch water main.

“It won’t increase pressure, but it would make service more reliable there,” Lamie said. It would also let the city phase out a standpipe storage tank on Ipswich Street. The city needs that tank now to provide emergency pressure in case of a fire.

“But water just sits in that tank otherwise, getting stale,” Lamie said. “If there ever was an emergency, it introduces old water into the system and that’s a problem. Having this 24-inch line gives us the supply we need, and we can eliminate the Ipswich standpipe and the problem.”

The water main project would cost $673,000. The district would borrow money to do the work from the state’s revolving loan program.

“In addition, we have higher costs for electricity and water treatment chemicals,” he said. Pavement costs for maintenance work have increased as well.

The water district last increased water rates in 2005, with an 8 percent hike.