A pneumatic/hydraulic wave generator is associated with the deep end of a swimming pool and includes a pneumatic system with a pair of inner caissons and a pair of outer caissons. The caissons communicate with the swimming pool through a submerged passage. A pneumatic system includes a motor-driven fan which communicates selectively with duct lines to the caissons through a pair of two-position air directional valve assemblies. When the caissons are actuated with pressurized air from the fan, the water levels therein are driven down, creating waves in the swimming pool.