Norwich — Nearly three years into a $200 million project to build a new wastewater treatment plant, Norwich Public Utilities says the project is about 80% complete. Construction began in November 2023, and is expected to complete in 2028. Both plants are on Hollyhock Island, and the current one continues to operate during construction of the new one. “The analogy we use is changing a flat tire without stopping the car,” said NPU spokesperson Chris Riley, one of several NPU officials who offered a tour of the facility last week. The current wastewater plant has served the city for nearly 100 years. It was upgraded in 1955 and again in 1973. NPU says each of the upgrades was designed to give the plant another 25 years of use. Construction workers were working Friday while NPU workers carried out regular plant operations. Plant Operator Dave Grundwalski said the construction constantly changed the path plant workers take in and out of the facility. Water/Wastewater Utility Project Engineer Matt Hross began the tour showing a new concrete “influent junction chamber” — where the three wastewater pipes carrying sewage and storm water to the plant will meet. The three pipes are the Cove Street Force Main, the Rose Alley Force Main and the Yantic Interceptor, a gravity line that brings sewage to the plant from homes and businesses along the Yantic River. A gravity line uses a downward slope to bring the wastewater in, while a force main uses a series of pumps to push the wastewater through.

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