Hull water treatment plant reopened, ending dumping of raw sewage into the Atlantic Ocean

Hull’s wastewater treatment plant is back on-line, halting the flow of raw sewage into the Atlantic, town manager Phil E. Lemnios said today.

The plant was re-activated at 11:50 p.m. Saturday using temporary pumps and generators, after being off-line since early Thursday morning, Lemnios said.

Crews from Hull, the Massachusetts Emergency Management Agency, and Department of Environmental Protection worked round the clock last week as temporary pumps and pipes diverted waste water out of the sewer system, instead being pumped through a manhole, over a rocky area on the beach, and across a stretch of sand into the bay.

An estimated 10 million gallons of raw sewage flowed into the ocean during the two and a half days the plant was down, Lemnios said.

“The alternative would have been several thousand homes here in Hull would have started backing up with sewage, so we had to do it,” Lemnios said.

Under the provisional system, the sewage is being disinfected and treated, just as it would if the plant was fully functional, Lemnios said. The treated sewage is then sent through the plant’s outfall pipe hundreds of yards offshore.

It is still unclear just how much damage 30 feet of raw sewage flooding caused the plant though “at this point, the damage to the control system and pumps appears to be extensive,” Lemnios said.

Officials are still unsure what caused the plant to flood, though excess rainwater helped to overwhelm the system, Lemnios said.

The plant, located just past the Hull Yacht Club, is run by private company United ­Water under contract with the town and has operated the plant for more than a ­decade, Lemnios said. The company has no record of safety issues, he said in an interview with the Globe on Thursday.

United’s contract with the town expires in June, Lemnios said, though Lemnios said it is premature to consider a different operator for the wastewater plant.

Based in Harrington Park, N.J., United operates in 21 states and runs more than 100 municipal water systems, according to the company’s website.

“United Water has been a good operator for us for many years,” he said.