The ultimate engineering of the magical, man-made, Ko Olina Lagoons can be laid at the feet of one Herbert Horita. They were designed to be continually cleaned by natural ocean currents while serving the needs of the community without concerns of chlorine or chemicals. Sand for the beaches was brought in from the neighboring island of Lanai. The ocean is no more than six feet deep in the portion roped off for swimming.
Ko Olina was once part of sugarcane plantations owned by the Campbell family. The land was sold in the 1980s. Herbert Horita, a developer with backing from Japanese investors, bought the section known as Ko Olina. He is the man responsible for creating the four man-made lagoons located there today. Work came to a screeching halt in the early 1990s when Japan’s economy crashed and Horita lost his backing. He had only completed the lagoons, the infrastructure and golf course, one hotel, and one resort condominium. Another developer stepped in and built up the remaining land to what Ko Olina is today.
According to an answer on Quora, the rock walls around the perimeter of each lagoon were built first. Once these retaining walls were in place, excavating crews dug out earth and simultaneously pumped seeping water out of the area until it was the desired size. Once they looked like open craters along the shore, it is rumored a bit of dynamite was used to break the dams and allow the ocean to flood inside. They considered using an excavator, but that was too risky. The lava rock walls could have caved in and the equipment (not to mention the operators) would have gone into the ocean. The islands of rocks at the entrances of each lagoon stops the large waves and allows only ripples inside. These “breakwaters” allow easy use of the lagoon for swimming and paddle boarding.
There are also three natural lagoons at Ko Olina. If you are a purist who can only relax on nature-made beaches, then these are for you. For the rest of the world, the ultimate engineering of the magical (and man-made) Ko Olina Lagoons are spectacular. One can easily walk from one lagoon to the next. There are shaded areas with benches for those who wish to simply enjoy the views. Take a picnic lunch and sun worship on the sand on these uncrowded beaches. There are also public restrooms, showers and water fountains along the walkway