Water Treatment Process

Beaker of Water

 

Rivanna is dedicated to providing reliable, clean, safe drinking water for our community, now and in the future.

The Rivanna Water and Sewer Authority operations at the South Fork facility in Charlottesville, Va. . Photo/Andrew Shurtleff

Konrad and Andrea taking water samples (photo: Andrew Shurtleff)

But before it gets to your house, it takes highly skilled, trained, and licensed professionals working around the clock to ensure things like consistent pressure, high-quality taste, and reliability.

 

Water Sources
Raw water from our reservoirs and rivers is pumped into the water treatment plants.

 

Sedimentation Basins at Observatory Water Treatment Plant

Coagulation/Flocculation
Once it arrives at the plant, the water is treated with coagulant, the pH is adjusted and water is rapidly mixed together to help disperse the coagulant. After the rapid mixing process, the water flows into flocculation basins, where the flow of water is slowed and slowly mixed so that the particulates stick together to form bigger particles called floc.

Sedimentation
Next, the water flows into sedimentation basins, where the heavy floc particles sink to the bottom and are removed.

Filters at Observatory Water Treatment Plant

 

 

Filtration
The water flows through large filters made of sand and anthracite coal. Filtration removes particles and microorganisms.

Adsorption
All of our treatment plants use Granular Activated Carbon (GAC) adsorption filters, a gold standard when it comes to water treatment to further increase our water quality.

Disinfection
We use chlorine to disinfect the water, and a residual level of chlorine is maintained throughout the distribution system as a protective barrier against microbial contamination.

 

Observatory Water Treatment Plant

Final Treatment

After chlorine disinfection, the pH of the water is adjusted and a corrosion inhibitor is added to minimize corrosion of the distribution system piping, and a low level of fluoride (0.7 mg/L, or ppm) is added to support good dental health.