AWWA MTC61199

This is a report on the first successful membrane softening plant in the state of North Dakota. During the 1970s, other attempts were made to utilize membrane treatment at other installations in the state. All were unsuccessful and abandoned within a year of start-up, at great cost. State regulators were apprehensive about using this technology further. This paper reports on the history and operations of the Gwinner, North Dakota Reverse Osmosis Water Treatment Facility, which was constructed in 1989-1990. Topics covered include: system deficiencies; raw water quality analyses for Gwinner, North Dakota; design and construction; finished water quality goals; plant operations including pretreatment and reverse osmosis; finished water quality at Gwinner Water Treatment Facility; and, membrane element replacement. Includes tables, figures.