Membranes are becoming the dominant technology in treating drinking water and wastewater. Membranes can be made in various geometries, but hollow fibers are the preferred form factor; they can be packed more efficiently, reducing the plant size and they are often easier to clean than alternative geometries. Nevertheless, during use, membranes will become fouled, which limits how much water can pass through them as well as potentially impacting the quality of the treated water. As such, membranes need to be cleaned frequently.