Groton - A special freeman's meeting on Monday voted 16-1 to move forward with plans to spend about $42 million to upgrade and modernize the city's aging water treatment facility.

The city plans to enter into an agreement with the state under the Drinking Water State Revolving Fund, in which the city would borrow money from the state and the state would issue the bonds. Monday's authorization replaces a vote last year which authorized $34 million for the 20-year project.

The project cost increased for three main reasons, said Richard Stevens, manager of the water division for Groton Utilities. First, engineers recommended the project include a 22 percent contingency fund - higher than the typical 10 to 12 percent - to serve as a buffer in case of unforeseen expenses. The project also required additional construction services, he said. Finally, the city opted to install two medium-sized emergency generators rather than one large generator, and replace valves in water mains.

Mayor Marian Galbraith said the city qualifies 30 percent in loan forgiveness from the state, which would leave the city with just under $30 million in debt to repay despite the higher overall costs, she said.

The impact on utility customers will not be known until the bond commission authorizes the bonds, Galbraith said. If the request were denied, she said the city would not borrow the money on its own but would revisit the project and get it done in stages, Galbraith said.

Under the worst case scenario, the project would increase water rates by about 21 percent for the more than 40,000 Groton Utilities customers. But the utility hopes to avoid "sticker shock" by phasing in increases gradually, she said.

Work on the Poquonnock Road plant would include construction of two elevated storage tanks along with upgrades to treat a variety of chemicals and organic contaminants to meet stricter water purity standards of the Environmental Protection Agency.

The project was placed first on the priority list of state projects under the revolving fund program for the current fiscal year, Stevens said.

The plant was originally built in 1939. The last major upgrade was done in 1960.

d.straszheim@theday.com

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