the spatial planning in the affected areas after the 2011 japan tsunami

8/10/2019 The Spatial Planning in the Affected Areas After the 2011 Japan Tsunami

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The spatial planning in the affected areas after the

2011 Japan tsunami

HIRANO, Katsuya

Disaster Information Management and Public Collaboration Division

IRIDeS, Tohoku University


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Who am I ?

I have taken part in reconstruction

planning for the city of Ishinomaki

and the town of Minamisanriku,

both in Miyagi Prefecture, and in a

visual quality assessment of the

new coastal embankment ofMiyagi and Iwate prefectures, as

an expert in urban design and

architecture for infrastructure.


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Comprehensive Planning Issues In Rural Areas

" Population decline and a super-aging society

Based on the latest population projection for 2012, the total

population of Japan will decrease from 128 million in 2010 to 87

million in 2060. In addition, the ratio of high-aged people, taken as

over 65 years old, will increase from 23% in 2010 to 40% in 2060.

" Decline of city/town centre

In rural areas, a low population density means a low service level of

public transport, a low service level of public transport means highvehicle owner-ship rates, and a high vehicle ownership rate causes

the service level go even lower. As a result of this vicious circle,

nearly every adult person has one vehicle in rural areas in Japan.

Needless to say, this vicious circle drives retail parks in the suburbs

to prosperity, while on the other hand, the city/town centre declines.


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Shutter Street

As a result of decline, shutter

street was born as a new term in

Japan. It means that closed shops

(shuttered shops) can be found in

rows on the street. Almost all

cities and towns in rural areas inJapan have several shutter streets

in the city centre.


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Comprehensive direction of city/town/village in

rural areas of Japan

compact city/town/village

The compact city/town/village becomes not a preferable direction but a

minimum requirement, because sustainability for municipal finance,

public transport, community activity and so on is a more critical

problem. Therefore, the compact city should be materializing in the ruralareas in Japan. It is possible to say that this is a common thought

between city planners in Japan.

The Smart-Shrinking City/Town is needed for rural areas of Japan.


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Dilemmas And Difficulties In Reconstruction Planning

" The Central Disaster Prevention Council (CDPC) of Japan decided the new

standard for tsunami prevention.

" Tsunami Level One (L1)

" The frequency of L1 is once per several decades to 150 years.

" Against L1, a principle for countermeasures is to use coastal protection

facilities, such as a coastal levee.

" Tsunami Level Two (L2)

" The frequency of L2 is once every 500 years or longer.

" Against L2, a principle for countermeasures is not protection but

evacuation of local residents.

" The tsunami on 11 March 2011 is included under L2.


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Decision Procedure of L1 and L2


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Once per 500 years vs. Actual Experience

The Decision of CDPC is Clear and Rational

" Life of Protectional Structure, such as a coastal levee, is not so long

" Protection level for major Japanese rivers is planned from 30-years flood

to 200-years flood

However

From a view point of survivors, L2 is not a Once per 500 years but a Actual

experienced one.

This di#erence in sense of time is quite critical and essential for reconstruction

planning.

!Municipal Governments seek a solution to protect a L2.


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Three Principles for L2 Protection

Principle of moving to higher ground (for Ria Coast)

Principle of Multi-layer Protection (for Plain Coast)

Principle of 2-2 rules (skip to explain because of time)


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Moving to Higher

Ground

Successful Example of Historical

Moving to Higher Ground

at Yoshihama, Iwate


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Moving to Higher GroundFishing Village will divide into

two parts in actual plan.


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Problem of Moving to Higher Ground

No one will be able to clearly explain how many people will live in the newly

developed higher ground after 30 years and how many people will move in as

the next generation.

The residences are located in the mountains and the workplace, such as a

fish-processing factory, is located behind the fishing port. This is directlycontrary to the concept of a compact city.

The tsunami washed out the historically

cultivated rural landscape. It is a severe

break in the regional tradition of thelandscape. However, Moving to Higher

Ground will abandon remained Streets,

views from streets, a shrine on the

hillside, and the composition or relation

of facility and nature.


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Multi-layer ProtectionHigh Embanked Motor Way

Stopped The Tsunami

Photo by Asia Air Survey


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Multi-layer ProtectionRe-construction plan of

Ishinomaki has a second Levee

First Levee

Second Levee


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Problem of Multi-Layer Protection

The life of second levee (High banked Road) will be shorter than 500 years.

According to engineering aspect, it will be strange solution.

In fact, National government and Municipal government had a severe conflict

to construct second levee


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Concluding Remarks

Re-construction planning has several dilemmas.

To rebirth a tsunami a#ected city/town/village as a sustainable one, we have

no e#ective method, because of lack of preparation.

The reconstruction planning in developing phase is very easy. Disaster will

become a great opportunity to make a infrastructure to support a

developing.

There is no comprehensive project scheme for a smart-shrink in Japan, in

spite of Japan has turn into shrinking phase. If we had a such scheme, Re-

construction plan would be much easier than actual situation.

These consideration will published in Division D, Journal of Japan Society for Civil Engineers (JSCE) on

next monthTitle is DIFFICULTIES IN POST-TSUNAMI RECONSTRUCTION PLAN FOLLOWING JAPANS 3.11

MEGA DISASTER:DILEMMA BETWEEN PROTECTION AND SUSTAINABILITY

the spatial planning in the affected areas after the 2011 japan tsunami

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