Multi-Hazard Mitigation Plan: 09. Tsunamis

Home

Chapter 9:Hazard Analysis—Tsunamis To describe tsunami-prone landscapes and community vulnerability to tsunamis on the Hawaiian coast, (USGS Scientific Investigations Report 2007-5208) used geographic- information-system (GIS) tools and publicly available geospatial data to create spatial overlays of hazard and socioeconomic data. Details on each of the socioeconomic datasets used in this analysis follow an overview of our analytical approach and the study area. Vulnerability calculations and comparisons are limited to the exposure and sensitivity of the urban footprint and certain assets, including developed land, populations (residential, employee, and tourists), economic assets and critical facilities. Exposure is defined as the amount of an asset (for example, the number of residents of a town) within a tsunami evacuation zone. Based on a spatial overlay of CDP (Census Designated Places) and tsunami-evacuation-zone data, there are 65 CDPs (hereafter called communities) in the State of Hawaii that contain tsunami-prone land. 13 of these are located in Hawaii County, these are shown in Figure 9-12. C otuity of Hawaii { xalu'ul.a 1 Kukuihacle Dmpahoehoe Puak5 Kalaoa Hilo Hax•aiian KAjJ na N H a w i L 1 Paradise Park ' 1 Hawaiian Holuuloa Beaches Kahnlu'u-Keauhou Captain Cook Mnamma-Napo op`o r T Nonh Pacific Oreav 0 10 iOM w Figure 9-12.Tsunami prone communities in the County of Hawaii To determine the number and type of residents in the tsunami-evacuation zones, USGS used block-level population counts and demographic data from the 2000 U.S. Census (U.S. Bureau of Census, 2001). Tax base is represented by current parcel values and is considered an attribute of community vulnerability because communities rely on property taxes for local services. Results of the GIS-based analysis are summarized by tsunami-evacuation zone and by CDP-based community. Figures summarizing these results are included below. 9-12 Hawaii County Multi-Hazard Mitigation Plan