HomeMy WebLinkAboutMulti-Hazard Mitigation Plan: 01. Introduction CIVIL DEFENSE AGENCY
COUNTY OF HAWAII
920 ULULANI STREET HILO,HAWAII 96720
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1. Introduction
Chapter 1:Introduction
CHAPTER 1 - INTRODUCTION
1.1 Purpose and Scope of the Plan
Purpose of This Plan
The purposes of this multi-hazard mitigation plan are twofold: 1) to protect people and
structures from harm and destruction; and 2) to minimize the costs and disruption of disaster
response and recovery. Hazard mitigation planning is the process that analyzes a
community's risk from natural hazards, coordinates available resources, and implements
actions to reduce risks. There are many benefits in developing a hazard mitigation plan: a
well-thought-out blueprint provides more direct access to a wide range of technical and
financial resources; the planning process promotes the development of a well- informed
citizenry knowledgeable about hazards; mitigation strategies are more integrated with other
community needs and goals; and the plan would improve the County's ability to recover after
a disaster. A hazard mitigation plan is a pre-requisite to receive federal disaster assistance
funding. In the past, the Federal Emergency Management Agency (FEMA) placed primary
emphasis on response and recovery. Recent changes in federal law marked a fundamental
shift in policy to focus on mitigation as the foundation of emergency management., For
disasters declared after November 1, 2004, state and local governments must have a miti-
gation plan approved by FEMA to receive pre- and post-disaster Hazard Mitigation Grants.
This plan is the update and revision of the original "Multi-Hazard Mitigation Plan: County of
Hawaii," of May 2005.
What is a Hazard?
A hazard is a natural- or human-caused event that has the potential to cause significant
injury, loss of life or property damage. "Disasters" are distinguished from "emergencies"by
the degree of response required. An emergency is where local resources are adequate to
respond. A disaster is when the marshaling of broader resources such as State and/or national
resources is necessary to assist with recovery.z Since 1977, Hawaii County has experienced
six events (three floods, a lava flow, and two earthquakes) that have met criteria for
Presidential declaration as a disaster area(see Table 1-1).
1 Disaster Mitigation Act of 2000(P.L. 106-390),which amended the Stafford Disaster Relief and Emergency
Assistance Act(P.L. 100-707)which in tum amended the Disaster Relief Act of 1974,P.L.93-288.
2 `"Disaster' means any situation,usually catastrophic in nature,where numbers of persons are plunged into
helplessness and suffering and as a result may be in the need of food, clothing, shelter, medical care, or
other necessities of life, and the governor of the State or the mayor of the County have declared a state of
disaster or emergency."(Hawaii County Code section 7-6).
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Chapter 1:Introduction
Table 1-1. Hawaii Count y Mayor Natural Hazard Events Since 1975
Event Date Areas Affected Disaster Declaration
Tsunamis
November 29, 1975 Halape,Punaluu,Honuapo,Kaalualu Unknown
Bay,Hilo,Kailua-Kona
Floods
Flooding February 2,2008 Countywide Mayor
Flooding Severe Storms, December 4-7,2007 Countywide,Statewide Mayor,Governor,President
High Surf,and Mudslides
Flooding October 25-26,2004 Kona Mayor
Flooding January 25,2004 Kohala,Hilo,Puna,Ka'u Mayor
Flooding November I&2,2000 Ka a,Pahala, Waiakea Uka,Komohana Mayor,Governor,President
Flooding high surf Novemher 17, 1996 Countywide Governor
Flooding September 19,1994 Hilo,Puna,Ka'u Mayor
Flooding August 12,1994 Hilo,Hmnakua Puna Ka'u Mayor,Governor,President
Flooding,high winds April 7, 1989 N&S Kohala,Hamakua Mayor
Flooding,high winds February 11,1982 N&S Kona Mayor
Flooding March 14-26,1980 Puna,Ka'u,N&SHilo,Hamakua,N&S Mayor, Governor
Kohala
Flooding,high surf,high Jarnuany 8-14, 1980 Countywide Mayor, Governor
winds
Flooding Novemher 15-17, 1979 Puna,Ka'u,N&S Hilo,Hanuakua,N&S Mayor, Governor
Kohala
Flooding October 9,1979 Ka'u Mayor
Flooding February 17-22,1979 Puna,Ka'u,N&S Hilo Mayor, Governor
Flooding,high winds January 12, 1979 Waipio Valley,N&S Hilo,Hamakua Mayor
Lava Flow and VOG
Kilauea March 25,31 and October Countywide Mayor
24,2008
Pu a'O'o March 3,2008 Puna Mayor
Kilauea eruption May 18, 1990 Puna Mayo,Governor,President
Kilauea eruption April 23,1990 Puna Mayor
Kilauea eruption February 4,1987 Puna Governor
Kilauea eruption December 9, 1986 Puna Mayor
Mauna Loa eruption March 29, 1984 E&SE portions of County Mayor
Kilauea eruption September 30, 1977 Kalapana Mayor
Earthquake October 15,2006 Countywide Mayo,Governor,President
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Chapter 1:Introduction
Event Date Areas Affected Disaster Declaration
Earthquake November 16, 1983 Countywide Mayor,Governor,President
Hurricane and High
Winds
High winds,high surf February 27,2004 Countywide Mayor
High winds,high surf January 14,2004 Countywide Mayor
Hurricane Jimena August 30,2003 Countywide Mayor
Hurricane Fernanda August 16, 1993 Countywide Mayor
Hurricane Iniki September 28, 1992 Countywide Mayor
High Winds February 16,1986 Hamakua,N&S Hilo,Puna Mayor
High Winds December 12, 1978 Waimea,Kawaihae,Waikoloa,Kiholo Mayor
Hurricane Fico July 19, 1978 Kapoho,Kaimu,Honuapo Mayor
Drought
June 5,2007 Kohala,Hamakua,Ka'u Mayor
May 25,2005 Countywide Mayor
August 20,2003 Statewide Governor
July 1,2003 Puna,Hilo,Hamakua,Countywide Mayor
August 10,2000 Kau,Kona,Kohala Mayor
March 14,2000 Hilo,Puna,Kau,Kona,Kohala, Mayor
Hamakua
July 22, 1999 Ka'u,N&S Kona,N&S Kohala, Mayor
Hamakua
January 30, 1998 Countywide Mayor
November 8, 1996 N&S Kohala,Hamakua Mayor
November 22, 1995 Hamakua,Hilo,Puna Mayor
January 10,1994,February Initially N&S Kohala,Ka'u,Kona; Mayor
22,1995(amended),March amended to include all districts
2,1995(amended)
May 11,1993 Kohala,Ka'u,Kona Mayor
February 28,1992 Countywide Mayor
February 10, 1986 Countywide Mayor
December 16, 1983 Countywide Mayor
March 14, 1983 Countywide Governor
February 15,1983 Countywide Mayor
July 15,1981 S.Kohala,Hamakua Governor
June 29,1981 Countywide Mayor
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Chapter 1:Introduction
Event Date Areas Affected Disaster Declaration
January 30,1981 Hamakua,S.Kohala Mayor
January 5,1981 Waiakea Uka,Puna Governor
Wildfire July 1, 1987 S.Kohala Mayor
Bold—Presidential Declaration
Hawaii Island is uniquely at risk to several natural hazards. Compared to the other counties in
this State, the relative risks are as follows:
• High Wind Storms. Comparable risk to the other counties; wind speed-up patterns occur
due to five dominant mountains;
• Hurricanes. Higher risk relative to the other counties due to the easternmost location, but
fortuitously low historic events;
• Landslides and Rock Falls. Higher relative risk to other counties, due to higher level of
seismic activity;
• Earthquakes. Higher risk relative to the other counties;
• Lava and VOG. Unique risk relative to other counties, as the only county with active
volcanoes;
• Tsunamis. Comparable risk to the other counties,but higher historic events;
• Floods. Comparable risk of flash flooding to other counties due to small drainage basins
with steep-walled amphitheater-shaped valleys; higher sheetflow flooding risk due to rela-
tively youthful geological development of defined drainage ways, especially in the leeward
areas;
• Dam failures.Fewer dams than other islands however potential for failure maybe greater
due to greater seismic activity;
• High Surf. Lesser risk to other counties on Northwest facing shorelines due to shadowing
effects of other islands, comparable risk on all other shorelines;
• Coastal Erosion. Of lesser concern is sandy beach erosion due to the geologically
youthful age of this island. Instead, sea cliff erosion is of greater concern to control
building too closely to the cliff edge.
• Droughts and Wildfires. Higher risk to droughts and wildfires relative to other counties
due to more extensive rural settlements that rely on water catchments, a dominant
agricultural industry that relies on rainfall, expansive open land area, and strong winds that
make wildfires difficult to fight.
• HAZMAT. The potential technological hazards of stored hazardous chemical materials
are under the planning of the Local Emergency Preparedness Committee (LEPC) per
Hawaii Revised Statutes Chapter 128D Environmental Response Law, and Chapter 128E
Hawaii Emergency Planning and Community Right-to-Know Act.
In each chapter focusing on the above hazards will be profiled in terms of:
• Description of the hazard;
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Chapter 1:Introduction
• Significant Historical Events;
• Probability of Occurrence;
• Risk Assessment Methods;
• Mitigation Strategies;
Scope of this Multi-Hazard Plan
This plan focuses on natural hazards, with a priority on disaster-potential hazards. Other
plans focus on human-caused hazards such as terrorism and hazardous wastes. Rather than
create separate plans for each type of natural hazard, this plan is a multi-hazard plan. A
multi-hazard plan has several advantages: 1) certain hazards cause cascading hazard effects
(e.g., earthquakes may cause landsliding, local tsunamis, or dam break flooding; hurricanes
cause wind damage and flooding); 2) priorities can be established to allocate limited
resources to areas susceptible to the most severe or frequent hazards; 3) areas identified as
susceptible to multiple types of risks may require special attention; 4) common responses
often apply to different hazards; 5) resources or mitigation measures can be leveraged where
they could benefit multiple hazards; for example proposed changes to building design
standards could consider both wind-loading(hurricane)and ground-shaking(earthquake).
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Chapter 1:Introduction
The Value of Mitigation
Emergency management includes preparedness, response, recovery, and mitigation. This
plan will focus on mitigation-- i.e., strategies to reduce risks. For example, retrofitting
bridges can keep them from washing out; installing hurricane clips can reduce personal and
property losses thereby reducing the need for public assistance. The money spent today on
preventive measures can significantly reduce the impact of disasters in the future. Reducing
overall economic losses and social disruption will enable the community to recover to pre-
disaster conditions as quickly and efficiently as possible, not to mention the costs saved. The
goal is to become a "disaster-resilient" county where our lifeline systems of roads, utilities,
infrastructure, and other support facilities are designed to continue operating in the midst of
high winds, rising water, or shaking ground. Critical facilities such as hospitals, schools, and
fire stations would be located in safe areas, rather than areas prone to high hazards. Resilient
structures would be built or retrofitted to meet the safest building code standards available.
Natural areas that provide buffers to flooding or other hazards would be conserved.
Coordinated Approach
Effective planning and response to hazard events involves local, State, and federal agencies.
This plan has been coordinated and is consistent with the State of Hawaii Natural Hazards
Mitigation Plan and guidelines of the Federal Emergency Management Agency(FEMA)3.
1.2 Organization of the Plan
The plan is organized into the following subject areas:
• Mitigation Planning(Chapter 2).
• Land Use, and Development(Chapter 3).
• Hazards Analysis (Chapters 4-15). All natural hazards that pose a potential threat to the
County of Hawaii were analyzed to determine the degree of threat posed by each. The
analysis provides a description of the hazard, significant historical events, probability of
occurrence,risk assessment techniques, and mitigation strategies.
➢High Wind Storms (Chapter 4)
➢Hurricanes(Chapter 5)
➢Landslides and Rock Falls (Chapter 6)
➢Earthquakes(Chapter 7)
➢Lava and VOG(Chapter 8)
➢Tsunamis (Chapter 9)
➢Floods (Chapter 10)
3 The federal Disaster Mitigation Act of 2000(P.L. 106-390)encouraged states and local governments to de-
velop integrated natural hazard mitigation plans. States and local governments with plans in place would be
eligible for faster funding and more effective risk reduction projects. Local Multi-Hazard Mitigation
Guidance,FEMA July 1,2008
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Chapter 1:Introduction
➢Dam Failures (Chapter 11)
➢High Surf(Chapter 12)
➢Coastal Erosion(Chapter 13)
➢Droughts (Chapter 14)
➢HAZMAT(Chapter 15)
• Shelters(Chapter 16). Facilities used for the purposes of sheltering residents in the event
of a hazard are presented in this chapter.
• Risk Assessment (Chapter 17). Those hazards determined to be of sufficient threat to the
County of Hawaii were further examined to determine the degree to which the population,
structures and land areas are vulnerable to the hazards. The analysis examined location of
population concentrations, critical facilities, community resources, major transportation
routes and infrastructure lines.
• Mitigation Strategy (Chapter 18). By overlaying the hazard areas and community assets,
problems and issues were identified. The strategy to address these problems and issues
consisted of clarifying mitigation goals and objectives, identifying alternative mitigation
actions, selecting and prioritizing the actions to be implemented, and developing an action
plan. Mitigation actions include improving warning systems and evacuation plans;
"hardening" critical facilities to withstand hurricane and earthquake forces; structural and
land treatment measures that contain or redirect natural hazards; planning and regulatory
measures to guide development away from hazards and establishing standards for
managing exposure to hazards; and incentive and educational measures to encourage
practices which are consistent with the disaster resistant community goals.
• Planning process and update procedures (Chapter 19). The last chapter documents the
extent of public participation and methodology used to develop the plan, as well as the
methods and frequency to keep the plan updated.
1.3 Overview of Hawaii County
1.3.1 Geography
The State of Hawaii consists of eight major islands (Kauai, Niihau, Oahu, Maui, Molokai,
Lanai, and Kahoolawe, Hawaii) and 124 small islands, reef, and shoals (referred to as the
Northwest Hawaiian Islands). Located in the middle of the Pacific Ocean, it is one of the
most isolated places on Earth-- 2,400 miles to the West Coast, 3,800 miles to Japan, 6 time
zones separating Hawaii from the eastern United States. The Pacific Ocean is rimmed by
active faults where tectonic earthquakes occur that can generate tsunamis (see Figure 1-1).4
4 Most of the tsunamis that have affected the Hawaiian Islands originated in the major earthquake belts, or
ocean trenches,that surround the Pacific Ocean. These massive earthquakes along faults are called tectonic
earthquakes. The devastating tsunamis of 1946 and 1960 were both generated by this type of tectonic
earthquake, the former originating in the trench along the Aleutian Islands and the latter along a fault near
Chile.
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Chapter 1:Introduction
Emmons,
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loo 80 75 70 65 }-
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20 3.0 10.0
Figure 1-1. Map showing all of the tsunamigenic earthquakes in the Pacific Ocean as colored circles.
Hawaii Island is the southeastern most island in the Hawaiian archipelago. The islands are
divided into four counties-- Kauai, City & County of Honolulu (Oahu), Maui, and Hawaii.
Hawaii County encompasses the entire island of Hawaii.
Although the Hawaiian Islands were all formed by volcanic eruptions, only Hawaii Island
still has active volcanoes. The size of Hawaii Island continues to grow as a result of the
ongoing eruptions. Related to volcanic building of the land mass are earthquakes. At
approximately 4,028 square miles, Hawaii Island, also known as the Big Island, is larger than
all the other islands combined. Hawaii Island was formed from the coalescence of five
volcanoes-- Kohala, Mauna Kea, Hualalai, Mauna Loa, and Kilauea. These five dominant
mountains create wind acceleration zones on the island(see Figure 1-2).
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Chapter 1:Introduction
Effective Wind Speed for the Island of Hawaii
(For Components and Cladding with Mean Roof Height not geater than 100ft)
District Boundary Land use CONTOUR
Major Road Agriculture ------ 90
Conservation 100
.J
Rural .......... 110
•., .' ��\ ��-•:-•~~��� Urban 120
-- -130
140
150
160
_.. — 170
180
I I r
I i
�+$ N
I ✓f
0 5 10 20 Miles
I I i I 1 I I I I
Figure 1-2. Wind contour map for the Island of Hawaii.The complex topography of the island creates acceleration
and decelerations of a 105 mph basic design event windspeed as shown.
As the geologically youngest island, Hawaii Island's landforms have not been weathered to
the extent of the other islands. Thus rainfall runoff flows in narrow V-shaped stream valleys
without broad floodplains or sheetflows in relatively undefined drainageways especially in
the drier leeward areas. The relatively immature reef development and related lack of white
sandy beaches is also characteristic of the youthful geologic age of this island.
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Chapter 1:Introduction
Located between 19 and 22 degrees north latitude at the northern edge of the tropical zone,
Hawaii's mild salubrious climate is due in part to location within the tradewind zone.
Hawaii's climate is notable for its low day-to-day and month-to-month variability. The
annual variation in mean monthly temperatures is only about 9 degrees F for areas at sea
level. While the climate is equable,the mountainous topography makes Hawaii Island one of
the most spatially diverse anywhere. From 20 inches in leeward areas to 300 inches in the
upper windward areas, this island experiences a range of moisture and temperature regimes
exceeding that found across the breadth of a continent.
The tropical conditions of the eastern Pacific are ideal for hurricane formation-- i.e., the
warm ocean water near the equator (combined with the cyclonic spin) within 10-20 degrees
north of the equator (see Figure 1-3). As the easternmost island in the State, Hawaii Island
has a slightly higher probability of tropical cyclone landfall, but historically very few events
have actually occurred.
Figure 1-3. Map of Tropical Cyclones Formed Worldwide from 1985 to 20055 6
5 Image from Wikipedia Website,Retrieved October 5,2009 from
http://en.wikipedia.org/wiki/File:Global tropical cyclone tracks-edit2.jpg
6 The points in the map show the locations of the storms at six-hourly intervals.
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Chapter 1:Appendix A
Chapter 1 —Appendix A.
Summary Digest Description of Changes from 2005 to 2010 in the
County of Hawaii Multi-Hazard Mitigation Plan — updated December 2010
Overall Reorganization and Reformatting of the 2010 Plan
To accommodate greater detail on hazards and risk assessment, as well as to more clearly
identify hazard mitigation activities and their specific impacts,the Hawaii County Multi-
Hazard Mitigation Plan has been substantially reorganized, and now has separate chapters
on each of the hazards. The number of hazards individually included in the plan has
increased from 7 to 13, plus an additional chapter on emergency sheltering,which is a
special consideration for island counties that cannot evacuate inland during hurricanes. The
total number of chapters has increased from S to 21. In short, this plan is a near-total
rewrite with the objective of greater clarity in addition to a major update of technical
knowledge.
The chapter on the Mitigation Planning process has been relocated to Chapter 2, providing
better linkage to the Executive Summary and Introduction for background on the
development of the plan for decision makers.
The number of graphic and photographic exhibits has substantially increased, in order to
provide better historical and technical exhibits for specific hazards, as well as illustrations
documenting new and ongoing hazard mitigation projects and the results of risk and
vulnerability analyses.
Each hazard-specific chapter discusses previous/current mitigation efforts and future
mitigation plan activities, so that specific recommendations are focused on each hazard.
These recommendations are then compiled and prioritized in Chapter 19.
It is anticipated that this new format will make the plan better enabled to accommodate
future updates in knowledge and mitigation actions in the future, and allow for hazard-
specific information to be exported to other planning efforts, such as community
development plans,the Hawaii General Plan, and the State of Hawaii Multi-Hazard
Mitigation Plan.
Chapter Description of Updates/Revisions in the draft 2010 Plan
Executive Summary
The 2005 plan discussed the primary The current 2010 plan developed a more concise executive
hazards,critical facility and population summary,and also summarizes some of the more significant
vulnerabilities,the mitigation strategy improvement in hazard identification and mitigation tools. The
and priorities are given,and an updated mitigation strategy and project priorities are updated.
exhaustive listing of various mitigation The most vulnerable facilities and populations are identified. The
actions is provided. detailed mitigation action listing is given later in Chapter 19.
1. Introduction
The 2005 plan provides an explanation of The 2010 plan updates the introduction with updates on hazards
the intent of the hazard mitigation plan, and the scope of the plan,as well as updated exhibits.
and a discussion of the geographic
profile of Hawaii County from a hazards
vs.community exposure perspective.
A l-1 Hawaii County Multi-Hazard Mitigation Plan
Chapter 1:Appendix A
2. Mitigation Planning
In the 2005 plan,discussed in the The mitigation planning effort included a major effort toward
chapter on the planning process at the greater public outreach meetings and community workshops,and
end. included a public opinion survey on disaster preparedness dealing
with both individual and governmental preparedness and
mitigation priorities.
3. Land Use and Development
The 2005 plan introduction provided an Demographics and critical facility information has been updated,
overview of Hawaii County geography, as well as the discussion of land use and development projections
population,economic profile,land use, per the Hawaii General Plan.
and projected growth.
4. High Wind Storms
In the 2005 plan,a high wind history in In order to differentiate the risks due to seasonal storms versus
Hawaii County is given. tropical cyclones(tropical storms and hurricanes),this separate
chapter now examines the high wind event history and windspeed
probabilities associated with seasonal climatology. This helps to
emphasize that seasonal winds have no direct relationship to the
much greater wind risk posed by hurricanes.
5. Tropical Cyclones
In the 2005 plan,historical events are This chapter reflects the substantial improvement in the state of
discussed,structural benchmark knowledge of the tropical cyclone hazard probabilities and the
vulnerability dates are given,and a effect of island topography in producing areas with amplified
summary of 2000-2001 research on windspeeds,new flood maps incorporating a hurricane flood
probabilistic hurricane hazard analysis is insurance study,indications of a pilot study of hurricane shelter
discussed. The needs for further work vulnerabilities,and new wind-resistant design and construction
on hurricane hazard and topographic provisions in the new State Building Code(2009).
wind speed-up are identified.
6. Landslides and Rock Falls
The 2005 plan included a brief discussion This chapter additionally includes a discussion of the substantial
on the various generic mechanisms for rockfalls generated by the 2006 Kiholo Bay earthquake,and
landslides and rockfalls in Hawaii. examines a 2009 slope hazard map developed for use in
earthquake loss modeling.Recommendations for improving the
landslide susceptibility maps are given for a mitigation planning
project that is starting in 2010 with the University of Hawaii.
7. Earthquakes
The 2005 provided a basic description of This chapter explains the fundamental seismological mechanisms
seismicity of the island of Hawaii and the for earthquakes in Hawaii,which is unlike continental seismology.
seismic hazard analysis basis for the The M6.7 October 15,2006 Kiholo Bay earthquake is described,
Uniform Building Code(now particularly its effects on the Kawaihae Harbor. The modern
discountinued). seismic hazard analysis used for the basis for the International
Building Code is explained. A new study to map soil conditions
affecting seismic ground motion is included. Structural
vulnerabilities of Hawaii island construction is addressed in several
new analysis of residential and critical facilities. New Enhanced
Hawaii Data for the HAZUS MH MR4 model for earthquake loss
estimation and planning has been developed.
A 1-2 Hawaii County Multi-Hazard Mitigation Plan
Chapter 1:Appendix A
8. Lava and VOG
The 2005 plan included a discussion of This new chapter adds an entirely new section on VOG—Volcanic
past eruptions and the basic lava hazard Gas Emissions,that was identified in public surveys as one the
zones,along with recommended tools three major concerns(earthquake,hurricanes,and VOG
for improved lava hazard mapping. mitigation). Additional information on past lava inundation
events is included. The lava hazard zone map is used in GIS
analysis to calculate the Average Annualized Loss(i.e.,the
county's economic risk)due to property damage by lava
inundation. There is an update on lava and VOG mitigation
activities,including several ongoing projects.
9. Tsunamis
In the 2005 plan,the fundamentals of Further historical data on tsunamis during the past 100 years is
tsunami generation,local history, presented. Additional information on tsunami detection and
warning,and the historical development warning is provided. A new tsunami inundation study using state-
of current tsunami evacuation maps are of-the-art modeling has developed updated inundation limits to
explained. use as the basis for updating the tsunami evacuation maps. A risk
assessment of tsunami-prone communities is presented. Further
work is identified,to included addressing tsunami risk in coastal
flood zoning and the upcoming development of new Performance-
Based Tsunami Engineering provisions for future building codes.
10. Floods
The 2005 plan included a description of The phenomena leading to flooding are described in greater
coastal and stream flooding hazard detail. The locations of Hawaii Dams are given for background
areas,and the basis for FIRM maps are information leading to Chapter 11. Historical damaging flood
explained. Areas of seasonally higher events are described in detail. The modern-day rainfall intensity
rainfall are generally identified. map is introduced. Areas of flooding are described by district.
NFIP exposure for Hawaii County is summarized. An analysis of
repetitive loss and severe repetitive loss properties is given and
mapped. Floodplain management activities of the County of
Hawaii are described in detail,and proposed county regulatory
update objectives are summarized. Future work is identified.
11. Dam Failures
Early research work on dam break This is an entirely new chapter dealing with the technological
modeling is described and the need for failure hazard of dam break inundation. A major effort in dam
further work on inundation modeling is condition surveys and hazard identification,and inundation
identified,due to the presence of 11 modeling has occurred in the years since the March 16,2006
earthern dams in Hawaii County. Kaloko Dam failure on Kauai. Regulatory requirements are
described. Ongoing efforts of the USACoE,State,and County Civil
Defense to create dam evacuation maps are discussed.
12. High Surf
This is an entirely new chapter dealing with damaging high surf
events and high waves due to hurricanes and tropical storms.
13. Coastal Erosion
The 2005 plan was confined to discussion This entirely new chapter focuses on coastal erosion mechanisms
of coastal escarpment erosion and and strategies.
coastal landslides.
A 1-3 Hawaii County Multi-Hazard Mitigation Plan
Chapter 1:Appendix A
14. Droughts
Droughts and drought impacts are Drought measurement and susceptibility indices are described in
described,and the need for further detail. Significant historical drought event losses are reported.
updates to include the Hawaii Dought Drought hazard areas are mapped. Drought monitoring tools are
Committee is identified. described. Drought mitigation initiatives from the Hawaii County
Drought Committee are reported.
15.Wildfires
Hawaii County wildfire suppression This entirely new chapter adds information on wildfire history and
resources are identified. losses,probabilistic wildfire hazard maps,and project initiatives
from the Hawaii County Drought Committee.
16. HAZMAT
This is an entirely new chapter on the potential technological
hazards of stored hazardous chemical materials,to summarize the
planning of the Local Emergency Preparedness Committee(LEPQ
per Hawaii Revised Statutes Chapter 128D Environmental
Response Law,and Chapter 128E Hawaii Emergency Planning and
Community Right-to-Know Act.
17. Shelters
This entirely new chapter identifies the presently available
emergency public shelter facilities in the County,and maps these
locations. A pilot study of structural and enclosure integrity of
several shelter buildings is described,using a recently developed
engineering assessment procedure of the Department of
Accounting and General Services. New building regulations of the
State Building Code for residential safe rooms and public building
enhanced hurricane protection areas are described. Follow-up
implementation recommendations for improving shelter safety
are given.
18. Risk Assessment
The 2005 plan Risk and Vulnerability This chapter adds a risk analysis of 80 critical facility buildings in
Analysis chapter provided a very the County of Hawaii and expected losses for earthquakes and
comprehensive overview of county hurricanes. Facility vulnerability rankings are given. A risk analysis
critical facilities,and characteristics of of the University of Hawaii at Hilo campus buildings is given with
the at-risk population. It indicated a high facility vulnerability rankings. Highway and bridge damage due to
priority for hardening of critical facilities. the 2006 Kiholo Bay earthquake are identified. Land Use data and
Loss estimation was based on results population data are updated. Improvements to the HAZUS MH
produced by Martin&Chock for the model capabilities are discussed,including the assembling of an
State of Hawaii. The need for future Enhanced Data inventory of Hawaii County buildings.
updates was indicated,stressing
additional development of HAZUS
capabilities and data improvements.
19. Mitigation Strategy
The 2005 plan described the County's This chapter has been updated. The Mitigation Goals and
mitigation goals and objectives, Objectives were updated, In that process,several items were
mitigation actions by hazard,priorities, identified as emergency response activities rather than having any
and project implementation actions. hazard mitigation effects,and these were removed. Mitigation
Actions by hazard are identified. The priorities for hazard
mitigation were updated. Implementation actions to address
these priorities are organized in a clearer listing.
A 1-4 Hawaii County Multi-Hazard Mitigation Plan
Chapter 1:Appendix A
20. Plan Maintenance
The 2005 planning process was Rather than just describe the need for plan maintenance and
described. general tasks,this chapter was revised to provide specific actions
and summary of specific ongoing hazard mitigation projects that
will impact the next adoption of the mitigation plan.Thus,this
provides a checklist of the resources expected for the plan
maintenance taskings.This should ensure continuity and
connectivity with ongoing and future work that should improve
the next plan.
21. References
This chapter has been updated to reference new material.
Appendix A FEMA LOCAL MITIGATION PLAN REVIEW CROSSWALK
A 1-5 Hawaii County Multi-Hazard Mitigation Plan