County expands capacity, preserves potable water

Gwinnett County, Ga., has completed construction of the F. Wayne Hill Water Resources Center (the Hill Center), which treats up to 20 million gallons of wastewater per day. The $185 million facility, which went online in February, provides needed capacity and — by incorporating a reuse component — helps the county preserve potable water resources.

Gwinnett has been one of the fastest growing counties in the nation for the past two decades, and it has expanded wastewater treatment capacity to meet population demands. As part of Metropolitan Atlanta, the county also has faced an environmental mandate to reduce interbasin transfer and pollution levels in the Chattahoochee River. That consideration, as well as drought conditions gripping the Southeast, prompted county officials to explore reclamation when it began designing the Hill Center in 1993.

Working with Wakefield, Mass.-based Metcalf & Eddy, the county designed a facility that provides conventional biological nutrient removal, followed by two forms of tertiary treatment: a conventional train with chemical clarification, filtration and biological carbon filtration; and a membrane train using microfiltration followed by nanofilters. “The facility consists, basically, of a wastewater treatment plant that is followed by a drinking water treatment plant containing more cleansing stages than most dedicated drinking water plants,” says Tommy Furlow, director of the county’s public utilities department. Performance exceeds the Class I reliability requirements set by USEPA.

The effluent is stored in three 20-million-gallon tanks and is used for irrigation of shopping center landscaping, golf courses and other developments. However, county officials believe that, because of the water’s superior quality, it could be used to replenish Lake Lanier, the county’s drought-stricken drinking water source. “The effluent from this facility is much cleaner than anything else that goes out from other treatment plants,” Furlow says. “It is, in effect, the cleanest water produced in the Southeast.”