Lessons from the Hiroshima landslide disaster



Massive landslides caused by heavy rain hit wide areas in the northern part of Hiroshima city on August 20, leaving 74 peo­ple dead and 44 oth­ers injured. Precipitation ex­ceeded 100 millimeters per hour in some of the areas. All evacuation calls for the residents were lifted on November 20. But the restoration work still continues four months after the disaster.


  Landslides triggered by typhoons, earthquakes and heavy rainfalls can play havoc in a matter of se­conds. Japan is susceptible to mudslide disasters be­cause it has many moun­tains with steep slopes. According to statistical data that covered the past ten years, about 1,000 landslides, both big and small in scale, occurred annually on the average. Other data shows that areas found to be at high risk of landslide disasters number as many as 520,000 across the country. This tells us about the importance of constant alert and preparedness against disasters. When heavy rainfalls are expected, we should be careful about landslide disaster information on TV or radio. When an alert is issued, we should take shelter as quickly as possible.


Two factors were primarily to blame for the heavy casualties from the Hiroshima disaster. One was a delay in sending out evacuation calls. The first landslide in the city occurred shortly after 3 a.m. But it was at 4:15 a.m. that the first evacuation call was issued. The municipal office admitted the delay, saying, “We miscalculated our precipitation analysis.”


The other was the way risk zones were designated under the landslide disaster prevention law. This legislation, enacted in 2001, is aimed to protect people from landslide disasters by designating risk zones and establishing effective warning and evacuation systems. It requires municipalities across the country to identify risk zones and take necessary precautions. The Hiroshima city government carried out its designation in 2001, but most of the devastated areas were not included in its list.


Mankind cannot be free from natural disasters. However, the number of victims can be reduced if each of us takes full precautions and if relevant information such as evacuation calls reaches us without delay.


(Written by Mikako Akai)