Abstract: Method and apparatus for creating in a water pool a wave for surfing, the pool having a reservoir at one end open to the pool beneath the undisturbed water level of the pool, a fan connected to the reservoir for expelling air from it and drawing water from the pool into the reservoir to store water above the undisturbed water level of the pool, and a valve for selectively sealing the reservoir against the intrusion of air and rapidly ventilating the reservoir so that the stored water flows into the pool by gravity at a velocity near its theoretical limit.