Groton — The town is reminding residents not to pour oil down drains or flush items like wipes, after sewage leaked from a manhole and it took workers several hours to unclog a sewer line.

At around 10 a.m. Monday, the town's Water Pollution Control Division received a call that sewage was leaking from a manhole in an area off of the southbound lane of Interstate 95 and near the end of Pamela Avenue, according to a town report. 

Chris Lund, assistant director of Public Works for the town, said a worker from a state Department of Transportation guardrail project in the area reported a manhole bubbling and an odor, so the Water Pollution Control Division staff went to investigate. The staff discovered "the sewer line obstructed and the manhole almost entirely filled with congealed grease, disposable wipes, personal hygiene products and various other items," according to the report.

"To use a phrase originally coined by British sewer workers, the resulting "fatberg" was the culmination of an agglomeration of things that should never, ever be flushed down a toilet or poured down a drain," the report said.

It took a truck with high-power water pressure and several hours of work to clear the obstruction, according to Lund. Workers finished breaking up the blockage at around 3 p.m., and he estimated that about six feet or more of grease was clogging the 8-inch diameter pipe.

"Fatbergs," though on a much larger scale, have made recent headlines. This month, a 210-foot fatberg was reported to be causing an obstruction in a sewer in the town of Sidmouth in England, and, in 2017, a 130-ton fatberg was found in the Whitechapel section of London, according to NPR.

Locally, towns and cities have reported that wipes clogged pipes and wastewater treatment plants, according to a 2016 report in The Day.

Lund said that while homeowners at times report blockages, they're not too common due to Groton's comprehensive maintenance program to clean and inspect, with robot cameras, the town's 136 miles of sewer lines.

The pipe with the blockage was last inspected and cleaned three years ago, and an ideal maintenance program calls for every five years, he said. Staff plans to talk to residents and businesses in the area to remind them of best practices.

"Residents are reminded not to pour cooking oil down drains. As it cools, it solidifies on the side of the pipes and eventually can cause blockages in your own sewer lateral or in the main sewer lines," the town report states. "In addition, plastics, disposable wipes, diapers and any other personal care products should be placed in a trash receptacle. These items can result in clogged pipes and damaged pumps and treatment equipment."

k.drelich@theday.com