Reverse osmosis (RO) technology has been used for the reduction of the salt content of water since the late 1960s. The RO membrane elements are available for a variety of desalination applications, treating water from sources ranging from seawater and brackish water to waste water for use in applications ranging from industrial and process water to drinking water. In recent years major advancements have been made in the flux and salt rejection capabilities of the membranes. It became apparent that a high flow seawater membrane element was needed particularly for cooler, lower salinity water and during the mid 1990s a product was developed to meet these needs. In 1999 high flow seawater elements, Koch Membrane Systems product Fluid Systems (TM) TFC(R) 2822HF-370 elements were installed in a new plant producing 5230 m(3)/d process and boiler feed water for EDIPOWER at Archi Marina San Filippo del Mela - Sicily, Italy. This paper is a case history describing the plant and looking at the performance of the membrane using Koch Membrane Systems NormPro((R)) to normalise the data.