AWWA MTC57547

Foss Reservoir, located 12 miles northwest of Clinton, Oklahoma, was formed after a 3 mile long earth-fill dam was completed in 1961. One goal of this project was to provide drinking water to supplement local supplies for cities and towns in the area. The water in the reservoir proved to be unsuitable for this purpose, as it contained 900 mg/l of hardness and 1000 mg/l of sulfate with a total dissolved solids (TDS) of 1600 mg/l. The towns had to wait 10 years until desalting technology developed to the point where building a treatment plant was considered practical. Working with the Office of Saline Water, both Electrodialysis (ED) and Reverse Osmosis (RO) were pilot tested and bids for a 3-MGD plant were received. ED was selected, with one of the major factors in the decision being a 7-year membrane warranty being included in the offer. The ED plant completed its startup performance test in October 1974 and has been in operation for the past 28 years. At the time of startup, this plant was the largest capacity membrane desalting plant in the world. Construction on a plant renovation and capacity expansion project that includes replacement of the desalination equipment started in October 2002. This paper discusses the plant history and the development of the renovation plan. Includes tables, figures.