"Exxchange" dynamic membrane processes consist of the Exxflow tubular cloth dynamic membrane support filter system combined with the appropriate membrane material suitable for the removal of certain compounds from waters. Iron and manganese can be removed using pre-oxidation with very short contact times. A major advantage over conventional filtration systems is its ability to deal with relatively high concentrations (up to 5 mg/l) without the need for a prior sedimentation stage. The use of powdered activated carbon (PAC) as a membrane has enabled the removal of Atrazine from a groundwater (0.3 to 0.5 ug/l) to concentrations below 0.05 ug/l using a PAC dose of less than 30 mg/l. Powdered ion exchange resin can be used to remove nitrate as a continuous process. The used resin is separated from the water, regenerated using brine, washed and then returned for reuse in the process. Groundwater containing 65 mg NO3/l has been reduced to 15 mg/l in pilot plant experiments.