Tapping into a global knowledge database to deliver the largest DAF facility in North America. To comply with the requirements of the Surface Water Treatment Rule, the Greenville Water System (GWS) retained Black & Veatch to provide engineering services for the study, planning, design, and construction of a new water treatment plant to filter two previously unfiltered supplies. Black & Veatch has provided engineering services for GWS since 1948.

Black & Veatch pilot tested a common European treatment process to demonstrate that dissolved air flotation (DAF), prior to filtration, outperformed other treatment technologies and was the most cost-effective alternative. Dual media and deep bed anthracite monomedia filters were evaluated. Dissolved air flotation followed by filtration produced treated water of excellent quality, with respect to turbidity and disinfection byproduct formation. The most effective filter was 1.5-mm anthracite monomedia, 72 inches deep at a filtration rate of 6 gpm/sf.

With construction now complete on the 75 mgd plant, it is the largest DAF facility in North America. Located in South Carolina, it has three 25 mgd treatment trains, each consisting of low head loss static mixers; four 6.25 mgd flocculation and DAF basins; and four deep-bed monomedia filters. Chemical feed systems include alum, sodium hydroxide, potassium permanganate, hydrofluosilicic acid, polyphosphate, aqua ammonia and chlorine.