Riding man-made surf typically means catching choppy, underwhelming swells in short five-to-10-second spurts. A project known as the Kelly Slater Surf Park, designed in partnership with its 10-time world-champion namesake, generates currents that provide surfers with rides of a full minute or longer. Waves form at the outer edge of the five-million gallon circular tank and break as they run up the pool floor, which mimics the seabed as it approaches shore. The pools may appear in such locations as resorts and theme parks, and can be scaled up or down to cater to available space. But how will the park create these waves?