The Perstorp, industrial park in southern Sweden is faced with water shortage problems. One way to reduce these problems is through the reuse of recycled water. In this paper the results of treating 240 m(3) per day wastewater in a reverse osmosis (RO) plant are presented. High-quality water, which is used as make-up water in cooling towers, is produced from a difficult and varying feed. Severe fouling problems during the first year of operation have been solved and the reliability of the RO plant is now good. The only pretreatment employed before the RO plant is a bag filter. Despite no cleaning of the membranes, the membrane lifetime is 16 months, which means that RO treatment is economically feasible. The savings made by using the RO plant emanate from reduced use of fresh water and lower discharge charges. (C) 2004 Elsevier B.V. All rights reserved.