The water is then mixed slowly and another chemical called polymer is added. The particles are then much larger. The water then enters large tanks called settling basins where the heavy particles settle. Other chemicals are added to remove minerals in the filters. The water is then filtered through sand and anthracite to remove remaining fine particles.
Chlorine is added to kill harmful bacteria, protozoans and viruses.
Lime or caustic soda and a corrosion inhibitor are added to maintain pH and minimize potential for corrosion City distribution lines and household plumbing. Fluoride is added to aid in the prevention of tooth decay. The City of Wilson obtains its water supply from two surface water sources. The first source is Contentnea Creek and consists of the Buckhorn Reservoir and the downstream Wiggins Mill Reservoir. Buckhorn Reservoir is the City's largest water supply reservoir and is an impoundment on Contentnea Creek approximately 12 miles west of the city.