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accompany the survey team on August 17, 2005, when the high tide reached 3.17 feet, but the wave and wind conditions were much less. 2.4 Tsunami Risk 7 According to the Atlas of Natural Hazards in the Hawaiian Coastal Zone, the Kapoho area has a high tsunami ranking. The Kapoho area is vulnerable to both local and distant tsunamis. For local tsunami activity, the history of tsunamis coincides with the history of earthquakes in the area (See Section 2.2). According to the Atlas of Natural Hazard, during the 1868 earthquake, a tsunami was generated that washed away 180 houses on the Kau-Puna coast and drowned 46 people. The port town of Keauhou, near Halape, was completely destroyed and is no longer found on maps. During the 1975 Kalapana earthquake, a tsunami was also generated along the coast and two campers were killed by the wave at the Halape Campgrounds in Kau, boats and piers were damaged in Hilo, houses were destroyed on the Punaluu coast, and fishing boats were sunk in Keahou Harbor south of Kona. For distant tsunamis, between 1812 and 1975, there have been 22 tsunamis that have had damaging consequences to the Hawaiian shoreline. These tsunamis came from tectonically active areas in regions of the Pacific, including Alaska, the Aleutian Islands, Chile, Japan and Tonga. Not all have affected the southeast coast of Hawaii county. The most notable that did include the tsunamis in 1946 (20 ft. runup), 8 1952 (10 ft.), 1957 (10 ft.) and 1960 (13 ft.). Both hurricane and tsunami risk are factors that are considered on the Flood Insurance Rate Map (“FIRM”) under the National Flood Insurance Program. From the FIRMs, sections of the coast are designated as flood prone (A zone) or wave prone (V zone) and appropriate construction measures are proposed, including elevating on piers and columns in the V zone. This elevation may protect against tsunami waves, if the elevation is sufficiently high. However, subsidence is not factored into the development of the applicable elevations, so over time, buildings may be placed at higher risk as subsidence proceeds. For this reason, the concept of free board or building extra elevation into the structure is strongly recommended (see Chapter 4). 2.5 Earthquake Risk The evaluation of earthquake risk in the Kapoho area is very important, because earthquake shaking is one factor that needs to be accounted for if structures 7 Atlas of Natural Hazards in the Hawaiian Coastal Zone, Fletcher, C.H., Grossman, E.E., Richmond, B.M., and Gibbs, A.E., 2002, prepared for State of Hawaii Office of Planning, NOAA, USGS, and UH SOEST. 8 From Atlas of Natural Hazards in the Hawaiian Coastal Zone 13