When the Crownhill water treatment plant (Plymouth, England) was expanded, on-site sludge dewatering with disposal of sludge cake to a landfill was incorporated in the design. A membrane filter press system was selected for sludge dewatering. This paper details the development of the membrane filter press and a detailed description of the Crownhill WTW and sludge treatment plant. Schematic drawings show the process through the plant and the operating cycle of the membrane press. Contractual provisions, performance testing, and operational experiences are summarized. One of the original design features that had to be changed was the core blow system; it was modified to keep the membranes fully inflated while the core blow was being initiated. A schematic drawing shows the original versus the final design of the system.