Norwich — The City Council on Monday approved projected increases in the cost of two major municipal drinking water system upgrades and allowing Norwich Public Utilities to finance the projects with grants and loans through the state Department of Public Health.

Neither project would increase municipal water rates, Norwich Public Utilities officials said, and some major components already are completed.

The first ordinance increased the project cost from $5.5 million to $6 million for three major upgrades to the Deep River Reservoir and the water delivery system, including the recently completed 1-million-gallon water tank in Lebanon and the relining of water mains from that reservoir to the city.

A third aspect of that project calls for replacing a “critical” pump and drive system to deliver the water to Norwich customers, Norwich Pubic Utilities Assistant General Manager Christopher LaRose said.

“Three quarters of the water supply in the city of Norwich comes from that pump,” LaRose said during the City Council public hearing on the ordinances.

The $500,000 increase will cover the replacement of a valve found to be defective during the project work and to remove asbestos and replace some aging control room equipment at the Deep River water treatment plant, LaRose said.

“By incorporating it into the project now and financing it over 20 years, there will be no increase in rates,” LaRose said.

Because both projects are being financed through grant and loan agreements with the state through the drinking water revolving fund in the Clean Water Act and not by city bonding, the projects did not go to a referendum, LaRose said.

All projects over $800,000 financed through city bonding must be approved by referendum.

The second ordinance increased the project cost from $5.4 million to $6.1 million for two major water line upgrades from the Stony Brook Reservoir. The project calls for replacing sections of a 1920s-era cast-iron water line and relining other sections with new PVC plastic pipe.

“Both are modernization of water infrastructure,” NPU spokesman Chris Riley said. “The equipment being replaced is used around the clock for decades at a time.”

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