What is SCWD? SCWD is a water switching or current generating device. SCWD switches or alternates water in two or more directions, depending on set up. It is an excellent water current generator for both salt water and fresh water environments, whether tank or pond. SCWD also has garden applications. It may be installed in statuary to create alternating or switching water flow from one spout or outlet to another or create decorative displays in garden ponds. The patented device, which requires no electricity, directs water between two outlet ports at varying intervals. The higher the volume of water flowing through the SCWD, the faster the switching response.