AWWA JAW39579

A questionnaire was sent to membrane filtration plants worldwide regarding their capacities, operation, water quality, and costs. The total plant capacity of all utilities responding was 49 mgd (185,500 m3/d). About 90 percent of the existing plants have design capacity < 1 mgd (<3,800 m3/d). The largest plant is a 15-mgd (57,000-m3/d) ultrafiltration plant currently being commissioned in France. Source waters for the plant included both groundwater (35 percent) and surface water (65 percent) and were not necessarily limited to high-quality waters. Although influent total coliform concentrations ranged from 1 to >1,000/100 mL, none of the plants reported the presence of coliforms in their permeate. The current treatment unit cost for membrane filtration ranges from <$0.50/1,000 gal (<$0.13/m3) for plant capacities >5 mgd (>19,000 m3/d) to as high as $2.50/1,000 gal ($0.66/m3) for plant capacities of 0.01 mgd (38 m3/d). Capital and operation and maintenance costs of membrane filtration are expected to continue to decline. Includes 20 references, table, figures.