NISKAYUNA — The town is moving ahead with plans for a multimillion-dollar upgrade of its sewer treatment plant, which has operated at capacity for a number of years and has at times discharged partially treated sewage into the Mohawk River.
The town has been fined over discharges. Also, since 2010, the town has been under a DEC consent order banning new residential developments from hooking into the town’s sewer system because the town’s sewer plant has reached capacity.
Developments planned for Aqueduct Road aren’t affected by the ban because they will be connected to Schenectady’s sewer system.
According to town Supervisor Joe Landry, the ban has not yet prevented any residential developments from being built.
Niskayuna has bonded for $9 million to make needed improvements to the wastewater treatment plant, and plans to start next year.
The town’s plant on Whitmyer Drive is designed to process up to 3 million gallons of sewage per day.
On an average day, the plant handles 2 million to 3 million gallons of sewage.
But on days when there is heavy rainfall, the plant has had to treat up to 7 million to 9 million gallons of output, according to Richard Pollock, the superintendent of water and sewer engineering in Niskayuna. That occurs because rainwater runoff and groundwater enter the sewer system’s deteriorating collector pipes.
Because the plant’s capacity is 3 million gallons a day, some of the extra output — a mix of sewage and rainwater — dumps into the Mohawk River.
Niskayuna is not alone in this; the city of Amsterdam also faces similar problems.
The town of Niskayuna has been dealing with these issues since 2003, when the state first identified problems with the sewer system and ordered them to be fixed.
As part of a 2010 consent order agreement with the state, Niskayuna paid $7,500 in civil penalties and agreed to improve the plant and reduce storm water infiltration into the system by Jan. 3, 2016.
In July, the town paid the DEC another $15,000 in civil penalties.
Since the 2010 consent order, water and sewer crews have been working to make improvements to the system, said Landry.
Several years ago, the town purchased a grout truck — a vehicle with cables and cameras designed to go into the sewage system. It allows crews to pinpoint and repair cracks in the pipes within the sewage and stormwater drainage.
Crews have used the truck to make small repairs.
But Niskayuna will be delving much deeper into repairing the wastewater treatment plant in 2017, according to Landry.
The bond money will be spent on a more powerful generator, new tanks and a new disinfection system.
The plant on Whitmyer Drive was built in the 1960s, and needs updating, according to Pollock.
He said the plant has an emergency generator but it has the capacity to power just half of the plant.
The town is working to get a generator that will be able to power the operations of the entire plant.
Two secondary clarifiers will be replacing two of the older clarifiers within the plant.
“We’ve been using gaseous chlorine, but we’ll be switching to U.V. disinfectant now,” Pollock said.
Gaseous chlorine, while an effective disinfectant, can be dangerous for workers should they be exposed to it. The chlorine acts as a respiratory irritant that can damage the skin and eyes as well. The U.V. disinfectant is a safer alternative.
The town of Niskayuna has pledged to complete the improvements to the wastewater treatment plant by June 2018, although Landry hopes they will be completed by the end of 2017.
Clarification: A previous version of this story stated untreated sewage was being discharged into the Mohawk River during major rain events that overwhelmed the system. Town Supervisor Tom Landry said the sewage goes through some treatment before it is discharged, but that said treatment is “expedited.”