When New Milford’s $22 million sewer plant expansion opened to great fanfare in 2012, officials confidently predicted they could pay off bonds sold to finance the project by signing up new customers for its web of sewer lines.

The plan was that the commission would share responsibility for repaying the bonds with the town.

But new signups have gone so slowly that sewer officials worry they can’t meet their obligation. They have told Mayor David Gronbach that after this year’s $1 million payment is made, they can’t be sure of making another one.

Sewer Commission Chairman Frank Bidetti and Vice Chairman Michael Bensema declined to comment on the debt, referring all questions to Gronbach.

However, Bensema said efforts are being made to obtain new connections to one sewer line, built in 2004, which runs southward along Route 7 from Sunny Valley Road to the Brookfield border. Even today, nearly every residential and commercial property along the five-mile route relies on septic systems.

“Last fall, we created a regulation that when new construction comes in or a significant update to a business occurs, they have to connect to the line,” Bensema said.

Gronbach has urged the commission to focus on attracting new commercial hookups to existing sewer lines to help raise revenue.

“There’s a lot of excess capacity at the plant that could accommodate new users,” he said.

“They could actually make the bond payments with some changes,” Gronbach added. “We’re working on putting a system in place that would work to that end, (to) make some changes in how usage fees are charged. We have to make it attractive for people to connect.”

For a typical single-family home, the connection fee is $1,500. For other properties, including commercial customers, the fee varies by square footage, from $2,500 for properties under 5,000 square feet to $50,000 for those over 75,000 square feet.

These fees are separate from usage charges.

At this time, 2,581 residences and 1,351 commercial properties are connected to sewer lines. The plant has the capacity to process 2 million gallons of effluent daily.

Answering a query from Gronbach about expanding the sewer network to reach more customers, Bidetti said the sewer district cannot afford the cost of installing new lines.

The plant expansion of 2012 was made at the insistence of the state Department of Environmental Protection.

The facility on West Street, last updated in 1989, was well below capacity but had reached the end of its design life. It could also not meet current standards for removal of nutrients, such as nitrogen and phosphorus.

The DEP issued an administrative order in January 2009 requiring the town to begin work on plant expansion and upgrades by Sept. 30 of that year. The order required that plant capacity be doubled, to 2 million gallons.

The town and sewer district financed the $22 million project using a combination of state grants, low-interest loans and a bond issue. The loan, via the Clean Water Fund, was paid off last year.

stuz@newstimes.com; 203-731-3352