Lessons from the Great East
Japan Earthquake
The Necessity of a Resilient Society

Takehiko Imai
Director, Information Policy Department
Community Development Bureau
Sendai City1

Lessons from the Great East Japan Earthquake(Late May, 2014)

Damage to Sendai CityCountrywide damage

M9.0

M9.0

Surface area flooded bytsunami

45 km2561 km2

Casualties (deaths andmissing persons)975 persons

Appr. 19,000 persons

105,947 persons

Appr. 480,000 persons(All evacuation shelters were closed on July 31st)(Only in Iwate, Miyagi, and Fukushima Prefectures)

137,660 bldgs.

Appr. 393,000 bldgs.

Appr. 1.3 trillion yen

Appr. 16.9 trillion yen

Magnitude ofearthquake

Evacuees (Max.)
Houses partially orcompletely destroyed
Cost of damages

2Lessons from the Great East Japan Earthquake
Overview of earthquake disaster

Sendai Tobu Expressway served as a levee

10ｋｍ

5ｋｍ
Sendai Stn.

Flooded areas

Major damaged residential areas

Surface area of flooding: 4,523 ha

Damage to residential lots:
5,728 residential lots

From Sendai Recovery Report3Lessons from the Great East Japan Earthquake
Simulation of a Tsunami(1) Recreation of tsunami in the form of a spring tide
Tidal level: T.P.＋0.76 m
Sea embankment: T.P.+5.5 m
Sea embankment: T.P.+6.2 m(2) Presumptions made in the recovery plans
Tidal level: T.P.＋0.76 m
Coastal and river embankments: T.P.+7.2 m
Embankment of prefectural roads: 6 m

Embankment ofprefectural roads:6m

Maximum
inundation depths
0.5 m or less
1 m or less
2 m or less
4 m or lessSeaembankment: T.P.7.2 m

The inundation depth
in the residential areas
to the west of theembanked roads willbe 2 m or less.

Over 4 m

From Sendai RecoveryReport4

Lessons from the Great East Japan Earthquake
Basic approach to tsunami disasterprevention measures

EvacuateMove◆ Ensure there are facilities forevacuation■ Move to safe area inland

Multiple defenses■Mitigate tsunami damage by elevating
prefectural highways, etc.

Mitigate disaster damage with multiple
defenses such as rebuilding seawalls andlevees, replanting disaster-prevention
forests, elevating prefectural highways, etc.

Emphasis “escape,” and maintain hills
for evacuation, evacuation shelters,evacuation paths, etc.

(Sectional diagram)Protection from a major tsunami
Protection from a tsunami that will occur
once every several decades or centuries

Relocating inland

Urban areas“Comprehensive disasterprevention measures” usinggroup move to safe areainland.

Sendai East Road

Miyagi Prefectural
Route 10 (Shiogama—Watari)

Parks (slopes)

Evacuation facilities

Disaster-protection forests
Tide embankments

Evacuation roads

Beach
ElevateEmbankmentof
prefecturalprefectural
roads
highways

Evacuation slope

Teizan-unga

Ocean

From Sendai Recovery
Report5Lessons from the Great East Japan Earthquake
State of recovery public housing
Menishi 6-cho(expected completion in Mar. 2015)

Izumi Chuo-Minami(expected completion in Mar.
2015)

Direct construction by Sendai City andpublic solicitation of proposals of where topurchase land and build housing. Goal iscompletion by March 2016.

3,206
3,500

(Constructioncomplete)

2,725

3,000

2,008

2,500
2,000
1,500
1,000
500

576728

H26.3月末

H26.9月末

120
H25.3月末

H27.3月末

H27.9月末

H28.3月末

From Sendai Recovery Report6Lessons from the Great East Japan Earthquake
FY25

FY26

FY29

FY30

FY31 - 33

All districts
completedRestoration ofresidential lots80% completed

3206 bldgs.
completed▼Completed inside Sendai Port Rear Area No. 3 Park

Tsunamievacuation
facilities

13 facilities completed

Izuchi district
evacuation hill

Rebuilding ofcoastal parks

Elevated roads

FY28

Land development complete at move destinations

Group move

Disasterrecovery public
housing

FY27▼Groundbreaking Groundbreaking
in all districts
Groundbreaking

Evacuation paths
Gamo Kita-bu
land readjustment▼Project plan
decided▼Provisionalredesignation/groundbreaking

From Sendai Recovery
Report7

Lessons from the Great East Japan Earthquake
State of occupancy (number of households) of emergency housing

Occupancy (number of households) (overall)Jan. 1, 2015

Percentage

Prefab temporary housing

802 households

11.1%

Leased private housing

6,043 households

83.8%

Leased public housing

365 households

5.1%

Total

Approximate 80% of temporary housing isleased private housing.
* First example of mass use of existing
housing stock.

7,210 households

Change in occupancy (number of households)
14,00012,00012,009

11,192825
789

10,383
737

10,000

9,511
711

8,000

8,901
680

7,210
365

6,000

9,838

9,140

8,476

7,714

4,0007,201
6,043

2,000
0

1,346

1,263

1,170

1,086

1,020

802

End 3/12

10/20124/2013

10/20134/20141/2015

Prefab temporary housing

Leased private housing

Leased public housing

From Sendai Recovery Report8Lessons from the Great East Japan Earthquake
Disaster brings major
damages in an instant

A great amount of time andlabor is needed forrestoration/recovery

Build resilient society
9