A 30-year plan for the Wastewater Treatment Plant on Dinmore Road was presented to the Bethlehem Town Board on Wednesday, March 14, capping off a two-year Department of Public Works study.
The study was performed with the help of two consulting firms, Clough Harbour & Associates and CDM Smith, to help the town find the most cost effective way to maintain the aging plant as the population of Bethlehem grows.
“The facility is more or less 40 years old,” said Commissioner of Public Works Erik Deyoe. “There is a lot of existing original equipment, existing original unit processes, and obviously the town has grown over that period of time. So we were interested in looking at what the long-term needs are, looking at future growth, as well as where we have limitations and redundancies to see how we can make the treatment process more robust.”
According to Karen Clark, vice president of CHA, the plant was built in 1972 with the capacity to treat 4.9 million gallons per day. Upgrades to the plant were performed in 1992 and the plant was re-rated in 2003 to increase the treatment capacity to 6 million gallons per day.
Various pieces of equipment have been updated over the years, prolonging the life of the plant, according to Clark. A new air compressor was purchased in 2006 and a new dissolved air flotation thickener, which is part of the process to turn waste into “sludge,” was installed in 2010. Because of damages sustained from Hurricane Irene, a clarifier that separates “sludge” from water was replaced this year.
The companies performed an energy study and inspection of the facilities and equipment, a climate change study, a sludge reduction study and a capacity analysis for the project. They also performed an odor control review because of complaints from nearby residents and those visiting Henry Hudson Park.
According to Clark, the town currently processes an average of 4.22 million gallons of waste per day. Expected growth was then calculated over a 30-year period based on future projects before the Planning Board and portions of the town currently not connected with the sewer system.
By 2041, the town is expected to process an average of 8.49 million gallons per day, with Selkirk expected to be added to the sewer system around 2026.
Clark said in three years, screens would need to be replaced along with other minor improvements, costing about $2.2 million. In between three and 10 years in the future, clarifiers and a disinfection station will need to be upgraded, costing about $7.3 million. After 10 years, major upgrades will need to be performed totaling about $20 million. All of the projections include 3 percent inflation for future costs.
According to Clark, after the upgrades are completed the plant will be in good quality for years to come.
“This is the total long-term plan. Once you hit about 9 mgd the plant will take you into the next 20 to 30 years,” Clark told Councilwomen Joann Dawson.
Councilman Kyle Kotary asked if when considering the total cost of the upgrades, it might be cheaper to hold off on upgrades and build a new plant.
Deyoe said the infrastructure was sound, as well as much of the equipment that was upgraded in the last decade.
“The only thing I can say is we built a whole new plant that was only 2.4 million gallons per day, it did not exist before prior to that, and by itself it was $22 million,” said Clark.
As far as odor’s concerned, Brian Hilts, project engineer for CDM Smith, said it is not a huge issue and could be addressed when future upgrades are made.
Deyoe said sludge tanks are emptied almost every day except for holidays and weekends. That is when the smell is usually the greatest and the most complaints are received.
“We try to haul as late as we can, recognizing the situation. We want to be good neighbors in that area, but unfortunately this process does have an odor with it and there’s just no way really around that,” said Deyoe.