ULTRADRAIN™ consists of an impermeable polymeric sheet cuspated under heat and pressure to form a high flow dimpled drainage core. The core is then bonded to a layer of non-woven filter fabric. The filter fabric retains soil or sand particles as well as freshly placed concrete or grout, allowing filtered water to pass into the drainage core. Ultradrain also has a protection sheet bonded to the backside of the cuspated core providing protection for soft membrane barrier systems.