The Rivanna Water and Sewer Authority is installing a granular activation carbon filter system at Crozet’s water treatment plant on Rt. 240. Two large tanks holding 16,700 gallons each that will contain the carbon particles are being housed in a new steel structure and should be operating by autumn.
“It’s an advanced treatment and it’s much more expensive than alternative systems based on chlorine, but its the best filtration system,” said RWSA spokeswoman Teri Kent.
The system is being added at all five treatment plants operated by the RWSA in the county. RWSA is the wholesale water producer for the Albemarle and Charlottesville jurisdictions. Retail delivery of water to individual users in the county is the job of the Albemarle County Service Authority. The improvements are paid for from income from customers that was set aside for plant maintenance.
Crozet’s treatment plant, built in the 1960s to meet the needs of frozen food manufacturing, can clean up to one million gallons of water a day, drawn from Beaver Creek reservoir. The new system is the final stage of cleaning when byproducts of earlier disinfection procedures are taken out. Water will pass through the carbon filters under pressure before going to storage tanks near the plant and near Mint Springs that have two-million-gallon capacities. The carbon granules will replaced with fresh ones every year. “We’ll be monitoring to make sure that’s the right schedule,” Kent said.
This month the RWSA will issue a request for proposals to perform a Crozet water master plan, which is expected to be ready in 12 to 18 months.
“The plan will look at safe yield from Beaver Creek, at waste water capacity, and the need for more cleaning capacity,” Kent said. “We need to be ready for peak conditions.”
Crozet’s current daily demand is nearly 500,000 gallons a day, but at times of peak demand, 75 percent of the treatment plant’s capacity is engaged. “That makes the engineers nervous,” Kent said. In February, for example, Crozet consumed 14.4 million gallons of water. In the last couple of years daily demand has started to increase more sharply than previously.
“The first step is to nail down the number we need to build for,” she said. “What’s the population we will serve? The county needs to come to us with that. We’ve been following the growth. We need to be deliberate because it has to be built to last. We want to meet with Crozet citizens and community leaders. There’s a lot coming in the outcome of the plan.”
Construction at the Crozet plant will include a new entrance and landscaping, Kent said. The exterior of the new building will be red metal. It’s designed to allow the tanks to be removed if need be.
Meanwhile, the RWSA is replacing Crozet’s “finished water” pump station, which is small and worn out, and is also planning to build a flow equalization tank and pump station on the sewer line leaving Crozet by 2020. Its location is undecided, but it will likely be near the Lickinghole Creek Basin. Kent said new state regulations will also require improvements to the Beaver Creek dam spillway.