The head of the Passaic Valley Sewerage Commission says the agency's massive wastewater treatment plant suffered historic damage from Superstorm Sandy but that repairs are progressing and the plant could be fully operational soon.

JMN, Getty Images

Executive director Mike DeFrancisci didn't give a specific timetable.

Since a few days after the storm, the plant has been releasing about 240 million gallons per day of partially treated wastewater into New York Harbor.

During a plant tour Thursday, DeFrancisci said the plant's administrative offices were filled with five feet of water. A mile-long maze of tunnels and underground chambers was completely flooded with as much as 12 to 15 feet of water.

The plant in the eastern section of Newark is the largest of its kind in the state and fifth-largest in the nation.

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