Report on the State of Physical Infrastructure in Hawaii

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Unlike many other areas where a shift in tectonic plates is the sole causeof an earthquake, 95 percent of the earthquakes in Hawaii are linked tovolcanic activity. These earthquakes can occur before or during eruptions,or as magma (molten rock) travels underground. The earthquakesdirectly associated with the movement of magma are concentrated on thesouthern part of the island of Hawaii and along its Kona coast beneathtwo of the island’s active volcanoes, Kilauea and Mauna Loa. Kilauea isone of the world’s most active volcanoes and most of the earthquakes areassociated with incremental movement of the volcano’s flank towardsthe sea. A few of the island’s earthquakes are less directly related tovolcanism; these earthquakes originate in zones of structural weakness atthe base of the volcanoes or deep within the earth beneath the islands.Since 1952 there have been 34 eruptions, and eruptive activity hasbeen continuous along Kilauea’s east rift zone since January 1983. Veryshallow earthquakes frequently precede or accompany an eruption.Hundreds of such earthquakes make up swarms that commonly occurover a period of several hours or days before an eruption as magma forcesits way into a new area. These earthquakes are seldom large enoughto cause widespread damage, but they may produce extensive groundfracturing close to the potential eruption site. Once an eruption begins,the earthquakes usually diminish.The most recent and significant earthquake in the state occurred off thenorthwest coast of Kiholo, Hawaii in October 2006. Categorized as a 6.7magnitude event, the costs for repair and restoration of critical infrastructurefollowing the Kiholo Bay Earthquake are $100 million. Estimateddamage to infrastructure for the same event is more than $120 million.Engineers, seismologists, architects, and planners have carefully evaluatedseismic hazards related to building construction. They have devised asystem of classifying seismic hazards on the basis of the expected strengthof ground shaking and the probability of the shaking actually occurringwithin a specified time. The results are included in the Uniform BuildingCode (UBC) seismic provisions.The UBC seismic provisions contain six seismic zones, ranging from 0(no chance of severe ground shaking) to 4 (10 percent chance of severeshaking in a 50-year interval). The shaking is quantified in terms ofg-force, the earth’s gravitational acceleration. The diagrams on thefollowing page depict seismic zonation.14
Map of the 1997 Hawaii Seismic ZoneStrong local and shallow earthquakes (less than 20 kilometers or 12miles deep), especially along the west coast of the island of Hawaii, havethe potential to generate a tsunami which may impact the state withinminutes. The Pacific Tsunami Warning Center will assess and issuetsunami information bulletins and warnings, as required.Tsunami. A tsunami is a 365 day threat to the Hawaiian Islands andresults from large-scale seafloor displacements associated with largeearthquakes, major submarine slides, or catastrophic volcanic eruptions.Although landslides and volcanoes cause some tsunamis, probably 95percent of the tsunamis result from earthquakes under the ocean floor orbeneath the coast. The collapse of a large lava shelf on the coastline ofthe Big Island could also generate a destructive tsunami which may affectthe entire state within minutes.While tsunami events are not common, they have been responsible for someof the worst disasters experienced in our islands. Tsunamis account formore lost lives than the total of all other local disasters. Since 1837, 291people have been killed by tsunamis in Hawaii with most of the deathsoccurring on the Big Island as a result of the 1946 and 1960 tsunamis.Tsunamis are characterized as shallow-water waves and are differentfrom wind-generated surf waves. Wind-generated waves usually have aperiod (time between two successional waves) of five to twenty secondsand a wavelength (distance between two successional waves) of about300 to 600 ft. A tsunami can have a period in the range of five minutesto two hours and a wavelength in excess of 300 miles.15
Page 3: I. Why Infrastructureis ImportantPh
Page 8 and 9: IV. How to Usethis Report</
Page 10 and 11: The cost of infrastructure projects
Page 12: According to the 2006 census, the p
Page 17 and 18: material spills, contamination of f
Page 19 and 20: IX. Report Finding
Page 21 and 22: Table 3Statewide Inventory by Count
Page 23 and 24: Proposed Statewide CIP Expenditures
Page 25 and 26: About 55 percent or $7.9 billion in
Page 27 and 28: and the City and County of Honolulu
Page 29 and 30: Joshua Magno, Pacific Resource Part
Page 31 and 32: Project Funding Sources and Sponsor

Report on the State of Physical Infrastructure in Hawaii

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