Kawaihae is an unincorporated community on the west side of the island of Hawaiʻi in the U.S. state of Hawaiʻi, 35 miles (56 km) north of Kailua-Kona. Its harbor is one of only two on the island, together with that of Hilo.
Construction of harbor
The United States Army Corps of Engineers dredged the harbor and built the breakwall between 1957 and 1959 and brought the village back from obscurity. In 1970, construction of a small boat harbor began to the south of the main harbor entrance by several institutions under the name of Project Tugboat. It was designed as a test of the use of high explosives to create harbors in hard substrate and as a proof of the concept that small nuclear charges could be used for civil works projects. Over 100 tons of conventional explosives (roughly equivalent to the smallest nuclear charge that could be built at that time) were buried in the Kawaihae reef and detonated to clear the basin and the entrance. It is the home of Kawaihae Canoe Club. It also served as the launching point for the film Waterworld with Kevin Costner. The artificial reef or floating island was just off the coast with headquarters for the movie at the harbor.