Sewickley's manager has compared a request by the Leetsdale Municipal Authority to combine waste-water treatment plants to high school dating.

Last month, John Kroeck, chairman of the Leetsdale authority, proposed closing the Sewickley plant and having the community's sewage handled by Leetsdale's facility. Sewickley could save several million dollars by eliminating its plant, he estimated.

Sewickley council, which recently received a $6.6 million loan to upgrade its plant, declined. The borough has been planning improvements to its 52-year-old facility for several years. Officials questioned the potential for savings, noting that borough crews still would be responsible for maintaining existing sewer lines.

"They asked us to go to the prom at the last minute," Manager Kevin Flannery said. "We said no, and now it's like they are stalking us." Leetsdale made its offer not at the "11th hour, but at 11:59," he said.

The Leetsdale authority serves customers in Leetsdale, Edgeworth and part of Leet. It will complete a $7 million expansion of its sewage treatment plant next year. The larger facility will be able to handle waste water from additional communities along the Ohio River, Mr. Kroeck said in an interview this week.

The Leetsdale plant is on Sixth Street in an industrial park. Sewickley's plant is about 2 miles away at Ferry and Chadwick streets. It has long served customers in the borough and in Glen Osborne.

Plans call for Sewickley to provide treatment service to nearby Aleppo starting in 2011. Discussions about expanding service also have begun with officials in Haysville and Glenfield.

Sewage from those communities could be handled without an expansion in the plant's capacity, Sewickley officials said.

D. Mark Brooks, Sewickley's director of environmental services, noted that the $6.6 million upgrade will not increase plant capacity above the current maximum of 980,000 gallons of waste water per day.

The plant will become more efficient and more environmentally friendly, he said. Planned improvements include replacing a high-maintenance "headworks" grinder with a bar screen, which will filter out large objects before the waste water is treated. The items removed, which can range from construction materials to tennis balls, will be taken to landfills. Another element is a dewatering plant that will remove additional liquid from the sludge that remains after treatment.

Both of those processes will be carried out inside structures, which should further reduce any smells from the plant, Mr. Brooks said.

Improvements to the Sewickley plant represented good planning for the future, according to John F. Hayes, president of Glen Osborne council. He said he was skeptical of Leetsdale's claims for large cost savings if the Sewickley plant closed and sewage was pumped to Leetsdale for treatment.

"What has made the offer difficult to evaluate is that the Leetsdale authority never approached us until a few weeks ago," he said.

Mr. Kroeck, chairman of the Leetsdale authority, said his agency hadn't learned about Sewickley's plans until recently.

Sewage now treated at the Sewickley plant could be diverted to the expanded Leetsdale facility with the construction of a 3,000-foot connector line, he said. "That would eliminate $6.6 million in capital expense [for the Sewickley plant upgrade]," he said.

The two sides are far apart on the potential for savings under the two plans.

Mr. Flannery said most Sewickley residents will continue to pay about $147 per quarter, or $49 per month, for sewer service for at least the next five years.

That figure would jump to at least $175 per quarter if Leetsdale took over sewage treatment but left the borough to maintain its existing system and pay off its current debt, he said.

Mr. Kroeck estimated sewer fees would drop about 35 percent as a result of economies of scale from having a single, larger more modern plant.

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