There is broad interest among contactors in constructing the town’s Hawleyville sanitary sewer system expansion project, based on their attendance at a town conference on the project.

Fred Hurley, town public works director, said last week that 18 prime contractors, most of whom are based in Connecticut, attended a January 13 prebid conference on the sewering project, which is intended to stimulate economic development in the area near the Exit 9 interchange of Interstate 84.

Those attending the conference posed some technical questions on the sewer expansion project, Mr Hurley said.

The town first advertised for competitive construction bids on December 23. Those sealed bids are scheduled to be publicly opened on February 9.

Construction cost estimates for the sewer expansion project range between $2.8 million and $3.2 million, Mr Hurley said.

Because the sewering project is intended to stimulate economic development, property owners with holdings adjacent to the planned sewer lines may connect to sewer system or not connect, based on their preference, Mr Hurley said.

About 25 property owners have indicated they intend to connect to the expanded system, he said.

Mr Hurley said the town’s planning goal is to know before the sewer construction bids are opened, whether those property owners’ financial commitments to connect to the sewer system would cover the cost of the sewer expansion project.

“The bid award for the project cannot be made until all [financial] agreements are returned [to the town], to assure there will be enough money to complete the project,” according to records of the Water & Sewer Authority (WSA). Those signed financial agreements would be submitted to the town by property owners who would receive sewer service.

At a February 2014 town meeting, voters by an 81-11 margin approved borrowing $2.8 million to be spent toward the project. Grant funds also will be applied toward the construction project.

Fuss & O’Neill, Inc, the town’s consulting engineering firm, will analyze the bids submitted, providing information on the submissions to the WSA. The WSA is the town agency that oversees the two local sanitary sewer systems and the town-owned public water supply system at Fairfield Hills.

As planned, the expanded sewer system would extend from its current terminus near 164 Mt Pleasant Road eastward to the intersection of Mt Pleasant Road and Hawleyville Road. From that intersection, the sewer system would extend northward alongside Hawleyville Road, and would also extend eastward alongside Mt Pleasant Road. The sewer system would extend to 90 Mt Pleasant Road where there is a 34-acre parcel that is expected to be developed.

The expanded sewer system would provide wastewater disposal for a planned mixed-use complex off of Hawleyville Road, which would hold a 180-unit rental apartment complex, a church, and a diner.

Many of the sewer lines in the expanded system will be low-pressure sewer lines, which require trenches only four to five feet deep. Areas with gravity-powered sewers may require deeper trenching.

Because the low-pressure sewer system extension project involves the use of many individual “grinder pumps” to propel sewage through narrow-diameter lines, the design variables for the sewering project are somewhat more complex than that of a conventional gravity-powered sewer system.

The Hawleyville sewer system, which started operation in 2001, discharges wastewater to a regional sewage treatment plant in Danbury.

The town built its much larger gravity-powered central sewer system in the borough and adjacent areas to resolve longstanding groundwater pollution problems caused by failing septic systems. The central sewer system, which discharges wastewater at a Commerce Road sewage treatment plant, started operation in 1997.