Editorial: National Disaster Prevention Day a reminder to be prepared
Work is still under way to search for those missing after being hit by a series of mudslides in Hiroshima and to help the city recover from the disaster.
Numerous questions have been raised over the huge damage caused by the tragedy, such as why the lives of more than 70 people were lost, why the local authorities were slow to issue an evacuation advisory and why little progress had been made before the disaster in designating vulnerable areas as caution zones under the Act on Promotion of Sediment Disaster Countermeasures for Sediment Disaster Prone Areas.
It is indispensable for both the national and local governments to assess their responses to the disaster in detail.
There are people who were killed by the disaster and those who survived even though they were in the same areas. It is also important to analyze the behavior of the disaster victims and survivors to ascertain the difference between life and death.
Sept. 1 has been designated by the central government as National Disaster Prevention Day. We must learn lessons from the Hiroshima mudslides and put them to good use as countermeasures against future disasters.
Apart from mudslides there have been other serious water-related disasters such as floods and rivers overflowing in recent years. It is still fresh in people's memory that a powerful typhoon brought record rain to Izu Oshima Island south of Tokyo in October 2013, triggering large-scale mudslides and leaving 39 people dead or missing. Torrential rain that hit the Kii Peninsula in September 2011 -- half a year after the Great East Japan Earthquake -- also killed nearly 100 people.
The annual amount of rainfall throughout the Japanese archipelago, situated in a rainy region, surpasses 1,700 millimeters on average, nearly twice the world average. Moreover, rainfall is concentrated in the rainy season from June to mid-July and in periods when the archipelago is hit frequently by typhoons.
Rain not only brings essential water but also causes disasters. In recent years, localized torrential rain often dubbed as "guerrilla downpours," and large typhoons have hit Japan. Many areas in the rest of the world have been hit by floods triggered by large-scale hurricanes. Some experts have warned that the number of floods will increase because of the effects of global warming. It should be kept in mind that people across the world face growing risks of floods.
In implementing countermeasures against floods, particular attention should be focused on efforts to deal with urbanization, or population concentration in small areas.
The Hiroshima mudslides are the consequence of a housing development that began in the central part of the city reaching areas just at the foot of a mountainous region. Housing developments have been conducted in a similar way in numerous areas throughout the archipelago. In Tokyo and ordinance-designated major cities alone, there are 28,000 areas prone to mudslides.
On the other hand, little progress has been made in efforts to restrict housing developments in such disaster-prone areas. There is a wide gap between areas in the degree of progress in designating areas prone to mudslides as caution zones. Little progress in such efforts has been made in not only Hiroshima but also other urban cities such as Sapporo, Sendai and Nagoya. Keiji Furuya, state minister for disaster prevention, has suggested that the government intends to seek revisions to the Act on Promotion of Sediment Disaster Countermeasures for Sediment Disaster Prone Areas to make it easier for prefectural governors to designate disaster-prone areas as caution zones at their own discretion.
However, making it easier to make such designations alone is insufficient. The Diet should hold in-depth debate on how to prevent people from moving into mudslide-prone areas and whether to consider relocating those living in areas vulnerable to such disasters, among other points of contention.
About 70 percent of the Japanese archipelago consists of mountains, while the remainder is hills and low-lying areas. About half of Japan's total population is concentrated in urban areas and other regions that face high risks of floods.
In 2010, a panel of experts on countermeasures against large-scale floods within the government's Central Disaster Management Council released a report under the radical title, "Floods in the metropolitan area -- measures that should be taken to lessen damage."
In the worst-case scenario incorporated in the report, up to 6,300 people would die if the Tone River were to overflow and up to 3,500 people would lose their lives if the Arakawa River were to flood. In case a massive amount of water flows into underground spaces such as subway tunnels, the scale of floods would rapidly expand. Such floods would deal a serious blow to politics and the economy, just like a powerful earthquake occurring right below the Tokyo metropolitan area.
The Kansai and Nagoya regions face high risks of floods as their population is concentrated in areas at ground level and many typhoons pass these regions.
It goes without saying that it is important to step up flood-control measures, but the central and local governments must work closely to utilize land with the risk of floods in mind and consider how to reside in areas vulnerable to floods.
Although the accuracy of meteorological observations has been improving, it is still difficult to precisely and quickly predict localized torrential rain that lasts for only a short period of time. Such being the case, local government responses, such as issuing evacuation advisories, are called into question whenever a serious disaster occurs.
The Hiroshima Municipal Government has admitted that it was slow to issue an evacuation advisory at the time of the mudslides. The Cabinet Office has set guidelines that require local bodies to promptly issue evacuation advisories or orders without fear of being criticized for overreacting to disasters. However, many residents choose to stay home despite evacuation advisories and officials at local governments appear to often hesitate to issue such recommendations.
Regardless, local governments must not hesitate to call on residents to flee their homes if there is imminent danger. Therefore, the national and local governments should clarify the criteria for issuing such advisories by learning lessons from past disasters and by improving their practical measures to respond to disasters.
At the same time, citizens should raise their awareness of the need to be prepared for serious natural disasters. In a column he wrote for the Japan Meteorological Agency's annual report for fiscal 2012, Gunma University professor Toshitaka Katada pointed out that citizens have failed to take proactive action to fully utilize information on natural disasters to protect their own lives.
"It is not necessarily true that improvement in the accuracy of disaster information directly leads to the enhancement of disaster countermeasures," he wrote.
The phrase "normalcy bias" refers to the psychological tendency to underestimate the imminent danger people face even if they obtain information on the danger they actually face. Experts have pointed out that victims of tsunami triggered by the Great East Japan Earthquake showed this mental state.
Instead of simply relying on government organizations, all citizens should have enough knowledge of the areas they live in, and choose a location where they would take shelter or a location within their home where they would seek cover in case of a serious disaster.
If they face an imminent disaster, people should proactively gather information to pay close attention to any warning signs.
People have nobody but themselves to rely on to protect their own lives.
Of course, regional communities as a whole must help the elderly and other residents who are vulnerable to disasters. もちろん、高齢者など災害弱者は、地域全体で助けねばならない。
With this fully in mind, all citizens should enhance their preparedness for powerful earthquakes, tsunami, volcanic eruptions and other natural disasters.
毎日新聞 2014年09月01日 02時30分