Research Trend and Results

Deprivation/Recovery of coastal cities’
disaster-prevention facilities functions by theGreat East Japan Earthquake tsunami andthe construction of disaster-prevention cities’
lodgment functions and creation ofdisaster-prevention cities
KIUCHI Nozomu (Dr. Eng.), HeadUrban Disaster Mitigation Division, Urban Planning Department
KATSUMATA Wataru (Dr. Eng.), Senior Researcher
Urban Development Division, Urban Planning Department(Key words) Tsunami disaster-prevention city creation, Coastal city. Disaster-prevention facilities,
Great East Japan Earthquake
1. Foreword
In the Great East Japan Earthquake, due tomassive tsunami said to occur once in several
hundred years or a thousand years, many ofdisaster preparedness facilities such as local
government offices and hospitals, fire stations,shelters or the like became dysfunctional causedby flood and interference occurred in
independently dealing with disasters as cities. In
the “Research on disaster structuring support
technology for coastal cities.” being tackled by
the Urban Planning Department (fiscal 2012 –2014), research has been proceeded with disaster
preparedness facilities against massive tsunami
and the method for ensuring functions by
disaster-prevention urban city structuring.
2. Location of disaster preparedness
facilities and urban planning
According to an assumption of the biggest classof tsunami flood being carried out in each region
currently, many of disaster preparedness facilities
have been included in the flood zone, and its
relocation to highlands has been deliberated.
Meanwhile, many of such facilities are locatedadjacent to central urban districts, contributing to
the convenience for inhabitants in normal times.
In order for fast and sloppy relocations ofdisaster preparedness facilities not to invite cities’
declination in parallel with decrease in population,
increase in earthquake/inundation resistances forthese facilities and relocation to safer districts andidentification of alternative facilities to replace
existing functions, preferential functional
recovery after disaster, enhancement in resilience
for lifelines, ensuring delivery networks or thelike, shall integrally be carried out in harmony
with the future images of cities.
3. Survey results in afflicted cities

Last fiscal year, targeting devastated cities bytsunami in the Great East Japan Earthquake, weinvestigated damages of disaster preparedness
facilities and resulting interferences onensuring functions, the situation of functional
recoveries by compiling literatures and hearingor the like. Due to tsunami damages surpassing
presumption, although the measures prescribedin existing regional disaster-prevention plansvaried in many cities, as a result, the facilities’
spatialallocations
ofurbandisaster
preparedness facilities (including substitutefacilities)
andspatialallocations
inurban/regional levels and locational relations
with each facility and arterial roads or the likehave been found affected to not only facilities’
damaged conditions but also to its functions in
its emergency response and recovery /restoration periods. If aligned phenomena seen
in urban/regional levels with reference toensuring disaster-prevention functions, it leads
to the following charts.
4. Preparation for Nankai trough giant
earthquake
Currently, deliberating a scenario for ensuring
disaster preparedness facilities’ functions inTokushima and Wakayama Prefectures whereindicated presumption of tsunami flooding by
Nankai trough giant earthquake and we arediscussing methods to boost its effects.
[Reference] Urban Disaster Mitigation Division
Home Page: Current Study
http://www.nilim.go.jp/lab/jdg/index2.htm

a. Deprivation, Substitution and Relocation of Functions
continuancea) relocatiob)
c)continuancenb. Consolidation and Dispersal of Headquarter Functionsa)relocation andconsolidationc)b)multipolarity
relocationdifficult tocooperatecontinuanceand isolationc. Hierarchy of Stations for External Disaster Relief Teamsa)b)singlestationc)
operationtroops disperse
operation troops
deployd. Centralization and Decentration of Distribution Stations for Relief Suppliesb)a)singlestationhierarchicalsystemc)
assignation by typee. Hierarchy of Shelter Functions
placement ofmedicalb) treatment patrola)aid stations

f. Accesses to Disaster Preparedness Facilitiesb) mutual access viaa) access fromarteryarterial highwayc)

access via
trailsＨ
heliport
severedg. Different Use of Public Facilities according to Locations
original functionrecovery
evacuation
stationing
retreataggregation
accumulation
acceptancetemporaryrelocation

andPeripher
Hinterlan
Inlan
forwarding
aland regional levels observed in reference to ensuring disaster preparedness functions indFigure Phenomenad at cities’
tsunami disaster preventive cities