ELLSWORTH – The city’s new wastewater treatment plant superintendent, on his first day on the job, made an immediate impact Monday on one of the plant’s multiple problems.

Michael Harris, a Bath native with 17 years’ experience in wastewater treatment in Virginia, found a place where the Union River was leaking into the plant.

Harris, 35, told the City Council on Wednesday that he put a vertical extension on the pipe where river water was flowing into the plant at high tide and promised the Maine Department of Marine Resources he will cap both ends of the pipe to make sure sewage doesn’t flow in the opposite direction into the river.

Harris has other challenges at the plant, however, that are not expected to be so easy to overcome. The city has to find a way to keep heavy rainfall from overwhelming the system and causing illegal sewage overflows through another pipe into the Union River, for one. The city, which is waiting for a consent decree from the state because of the overflows, cannot cap the illegal second pipe where the overflows occur until it finds an acceptable place to divert the excess intake.

Harris told the council Wednesday he might be able to contain an additional 140,000 gallons of wastewater in existing tanks at the plant, if it is feasible to make the necessary connections and install the additional pumps.

The city also has to improve its sewage treatment capability, either by upgrading the existing Water Street plant or by building a new one elsewhere. A comprehensive upgrade could cost $10 million and a new facility could cost $14 million, city officials were told Wednesday.

Harris, who has won national team competitions in wastewater treatment plant operations, said the challenge of fixing Ellsworth’s problems attracted him to his new job. His and his wife’s desire to be close to their families was another reason they and their three children moved to Maine from Virginia Beach, where Harris worked for a larger wastewater district.

Though Ellsworth has a smaller plant, Harris said, it is no less important than the one he recently left. He said he is “very excited” to help the city solve its wastewater system problems and is willing to talk with any Ellsworth resident who has concerns about the plant.

“I have an open-door policy,” Harris said. “The plant’s going to go in a positive direction.”