inflatable rubber dams are cylindrical rubber fabrics placed across channels, streams and weir or dam crests to raise the upstream water level when inflated. the membrane is a multi-layer fabric made of synthetic fibre (usually nylon) and rubberised on one or both sides. the fabric is quite flexible and yet exhibits good wear-resistance characteristics. a layer of stainless steel mesh or ceramic chips can be embedded in the surface layer to reduce or prevent vandal damage.