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The Farmville staff wants to change the way the town wastewater treatment plant operates. Instead of using chlorine, they’re proposing a shift to treating the water with UV light. Originally, town staff had been looking into switching from treating the water with chlorine gas to a liquid version, to be safer. This has been a plan in the works since the chlorine leak two years ago. But then they noticed more than half of Virginia’s wastewater treatment plants have stopped using chlorine completely. That includes the plants in Dillwyn, Blackstone and Emporia. And that’s when the idea of using UV light entered the picture. 

When water comes into a treatment plant, it can have microorganisms inside. Typically, those have been eliminated in Farmville by using chemicals like chlorine. Instead of using chemicals, UV light shines on the water and changes the DNA of any microorganisms inside. It basically kills all of the germs and viruses or anything else that could be in the water. It’s a practice that’s been endorsed by the National Center for Biotechnology Information, as well as the National Sanitation Foundation. 

“Plus, it’s safer for the employees and the citizens because you don’t have to worry about any chlorine leaks,” said Farmville Finance Director Julie Moore, who was put in charge of the project by Farmville Town Manager Dr. Scott Davis. She gave a presentation on the staff’s idea to council members during their Wednesday, Aug. 7 work session. 

Harder to find 

Beyond safety, it’s also getting both harder and more expensive to find the chemicals needed to operate the wastewater treatment plant with chlorine, Moore said. First, it’s harder to find them and second, when they are located, the costs are significantly higher than expected. For example, to currently treat the water, the town uses chlorine. But while chlorine used to be between $400 to $500 per ton, now that’s gone up to $1,900 per ton. And you can’t release water filled with chlorine back into the river, so after the chlorine does its job, you put another chemical, sulfur dioxide, into the treatment plant to kill the chlorine. Before COVID, a ton of sulfur dioxide was $300. Now it’s $1,700 a ton. 

And there’s another looming problem, if the town decides to stay using chlorine. Parts of the town’s sand filter is currently corroded. Davis told the council when staff went to check the sand filter, they found everything in it at the bottom was corroded. 

First, an explanation. Sand filters help catch particles in water, even as tiny as some bacteria. But one of the particles that can create problems is phosphorus and so, the chemical alum is introduced into the water, to destroy that phosphorus. It also causes particles or bacteria to stick together and form larger, heavier material that gets trapped in the filter. 

However, while that’s all beneficial, it comes with a cost. Over time, alum turns the sand into slush, causing the filter to need to be continually replaced. That would be the corrosion mentioned earlier. 

It’s not cheap, with most options coming in around $420,000. The reason is that this isn’t normal sand, like what you’d find at the beach. The sand is modified, with certain edges to it and a certain size requirement. 

Currently, there are only two places in the U.S. where you can get that sand. The shipping costs alone from Texas, which is the closest option, for 144 tons of sand is $50,000 to $60,000. And yes, the town’s system uses 144 tons of sand in its filter. And every time the sand filter turns to slush, the town would have to go through this. Given Farmville’s current rate, pumping 1.1 million gallons of water per day on average from the wastewater system, that means a replacement every two to three years. And as Moore pointed out to council members, that $420,000 is what it costs to replace a filter now. No one can say what a sand filter will cost in 2026 or 2027. 

Making wastewater treatment change

So by switching to using UV light, the town would both eliminate the need to use all these chemicals and save the money involved with buying them. The UV light system uses a cloth filter, also eliminating the need to buy tons of sand and haul it up from Texas. 

However, the new UV system isn’t cheap. By itself, it would be between $2.5 million to $3.5 million to purchase. The town already has $600,000 set aside for the wastewater treatment plan. In addition, the town still has $2.5 million in American Rescue Plan Act (ARPA) money that hasn’t been committed yet. The town council had wanted to use that on water and sewer infrastructure, but Moore asked for them to reconsider. That ARPA money has to be committed by December of this year, which this project would allow them to do. To be clear, committed in this case means set for a specific project, with a contract signed with a contractor. 

As a result, the ARPA money can’t be used on Farmville’s planned water and sewer projects, because the town doesn’t have any contracts set up. That’s because they’re waiting for the current study to be completed, then the plan is to focus on the oldest ones and move down. Moore explained the council could still do that, but just with a different pot of money. 

Moore suggested that since the sewer fund makes money, council members could divert a portion of the revenue coming in every month. They could allocate that into a ‘repayment fund’, combined with an existing $1 million in the sewer fund, up until the $2.5 million to $3.5 million spent on this change is repaid. 

Weighing options

Council member Thomas Pairet said he supported the idea, but just wanted to make sure water and sewer projects weren’t pushed back as a result. 

“I want to make sure water and sewer don’t fall by the wayside,” Pairet said. “I have no problems with updating this wastewater plant, none. But I want to make sure we’re not going to neglect the water and sewer project.” 

Council member Adam Yoelin asked if staff could come back with a comparison, giving as best an estimate as possible for the cost of the current system versus what’s being proposed. 

No decision was made on the proposal. Staff agreed to collect the data being asked for and to bring it back to council, either this week or at a future date.