Once a year the lake at Waimea Bay fills up due to the winter rains. A river usually emerges and carries all of the collected water back to the ocean, once the surfers caught wind of the power that this river creates they began to beat the natural process and used it for what it was worth. The lake usually takes about 24 hrs to drain, and for most of that time these surfers get to ride waves that seem as if they will never end. Even though the video shows these guys speeding up the process by digging the trench so that the lake will begin to drain, it is important to know that this is a natural process and the beach goes unscathed by this occurance!