Silviase/jgov_v1.4_full_ann huggingface dataset:
### 3. Reinforcement of Countermeasures Against Tsunamis

The Great East Japan Earthquake resulted in one of the worst devastations from a tsunami in the country’s recorded history. Many tsunamis have occurred around Sanriku coastal areas and have brought about devastation. The disaster of this time showed that preparations that had been made were still not enough. Although various instructive events were carried out the last year to pass along the severe lessons of the tsunami caused by the Chile Earthquake in 1960 (commemorating the $ 50^{th} $ anniversary of the disaster).

The massive tsunami damages following the Indian Ocean Tsunami showed its destructive force to the nation and the whole world. We must recognize characteristics of tsunami disaster and verify what was useful with conventional protections and what was insufficient in consideration to current conditions of tsunami protection in order to make further efforts toward reducing tsunami damages.

The lessons learned from this huge tsunami which destroyed breakwaters, sea levees, coastal embankments, and seawalls, and which surged over inundation-estimated areas to swallow designated shelters was that it is necessary not only to review conventional tsunami estimation, but also to intensively reinforce countermeasures for tsunami evacuation to save lives over circumstances beyond assumption, without believing that the existing countermeasures such as breakwaters, sea levees, coastal embankments, seawalls, and hazard maps are eough. $ ^{1} $

Since tsunami disaster has a much lower frequency compared to damages by heavy rains, it is important to pass along to the next generation the lessons learned from the sorrowful disaster.

## I ssues with Current Tsunami Protection

Conventional measures against tsunamis have been the construction and maintenance of sea levees and seawalls. As for the current height of the sea levees, out of about 15,000km in total of seacoast protection facilities all over Japan, about 59% are higher than estimated tsunami heights; about 17% are lower; and for the remaining 24%, estimation tsunami heights have not yet been set or surveyed.

Even if it is almost impossible to restrain the largest class tsunami like one caused by the

earthquake last year, it is necessary to firmly promote the building and maintenance of facilities as having an effect in the reduction of the power of tsunamis (depending on actual situation in each area and with consideration to the validation of damage situations of the facilities destroyed by the tsunami).

As for soft policies, it is important to create a tsunami hazard map showing that which areas in the regions would be jeopardized, depending on the height of the tsunami, and the effects of breakwaters, sea levees, coastal embankments, and seawalls. The danger level of the estimated inundation area and facilities, can be precious information for evacuations.

Based on the lessons learned from the huge tsunami, scale estimation is a big issue. However, preparation for the creation of tsunami hazard maps are not yet sufficient. Only 53% of 653 coastal municipalities have prepared
tsunami hazard maps. In addition, only 41% of those municipalities have formulated concrete plans regarding tsunami evacuations.

Municipalities say they have not taken such measures because they don't know how to create hazard maps or evacuation plans. That means they need some technical support to progress these measures.

It is necessary to promote the preparation of tsunami hazard maps, and to try to enhance and amend existing maps.

Source: Cabinet Office (as of March 2010)

106: Formulation of Tsunami Evacuation Plans

Source: Cabinet Office (as of March 2010)

## Reinforcement of Tsunami Evacuation Measures

While reinforcing and enhancing such hard and soft measures under a certain assumption, we need to strengthen immediate evacuation measures intensively to save lives by any means, keeping in mind situations beyond estimations.

The best policy to escape from a tsunami is to immediately run up to grounds as high as possible. For that, checking evacuation places and routes is essential. Especially in the case of tsunamis caused by earthquakes whose epicenter was near (which doesn't allow a long time to evacuate), desirable evacuation destination is not farther but higher. It is also a big issue to take utmost consideration for evacuation support for disaster-affected destination people such as the elderly, the disabled, pregnant women, infants, etc. It is necessary to consider whether evacuation to higher ground outside of the inundation area is possible, depending on actual situation in the area. If such measures can not be taken or there is no higher ground within the inundation area, securing strong, high-rise buildings, should be required.

Only 21% of municipalities have designated tsunami evacuation buildings; 74% have not taken such measures. However, the number of designated buildings has been increasing year by year, and almost half of those are private facilities. It is necessary to promote the usage of existing buildings (including private buildings or condominiums),