The law for making the nation more resilient against natural disasters, approved by the Diet in December, calls on the central and local governments to compile plans to guard against the worst possible disasters such as earthquakes, tsunami, floods and landslides, so as to minimize the human and material damage from the disasters and provide for speedy recovery and reconstruction.
A basic plan adopted by the Abe administration in June, which needs to be reviewed every five years under the law, says the concentration of population, resources and economic activities in the greater Tokyo area should be reversed and redistributed to other parts of the country, so that the nation can survive massive disasters including a severe quake that is expected to directly hit the metropolis, or one that could occur along the Nankai Trough off central and western Japan.
The plan calls for building alternate railway and expressway routes, efforts to make more houses and buildings quake-resistant, development of new homegrown sources of energy, and so forth. One question will be how to pay for all these projects under the nation’s strained fiscal conditions.
Meanwhile, prefectures and municipalities across Japan are being urged to put together plans to defend against worst-case disasters that could hit their areas through such efforts as beefing up embankments, preparing evacuation plans for local residents and securing shelters for the evacuees.
The local governments — which should be in a better position to grasp disaster risks in each area and are primarily responsible for protecting the local residents when disasters hit — need to review their current anti-disaster systems to identify where they are vulnerable, and make sure to share the sense of danger with the residents.
The landslides that devoured houses in the hilly outskirts of the city of Hiroshima on Aug. 20, killing at least 72 people, illustrate the risk of assuming that safety measures introduced under central government policy are in place when it may take years for local authorities to implement them.
After torrential rains caused similar mudslides in Hiroshima Prefecture that left 32 people dead or missing in 1999, the government introduced a law in 2001 that empowered local authorities to designate areas vulnerable to landslides, for which municipalities would prepare hazard maps and make evacuation plans for residents.
In areas designated especially as being at high risk of landslides, development of residential land is to be restricted and prefectural governors may recommend that owners of houses in particularly vulnerable locations move out.
However, much of the areas devastated by torrents of mud, rocks and debris in the Aug. 20 landslides — where houses were built on unstable ground at the foot of mountains to make way for the rise in the city’s population — have not been designated as such risky zones.
While there are nearly 32,000 locations in Hiroshima Prefecture that the central government identifies as vulnerable to landslides, only about 11,800 have been designated as such by the local authorities.
Work on the part of local governments to designate landslide-risk areas involves research of the local terrain at numerous locations. Progress on this reportedly has been slow because of manpower and budget shortages.
In addition, people who live in such areas are said to shun the designation by local authorities as officials try to obtain their consent, because a landslide-risk designation tends to push down real estate values.
As a result, the very purpose of the system — to make people fully aware of the specific disaster risks in their communities — has not been served in many vulnerable areas.
The problem is not unique to Hiroshima Prefecture. Thirteen years after the 2001 law was implemented, only about 70 percent of the roughly 525,000 locations across Japan identified by the land ministry as vulnerable to landslides have so far been designated as such by local authorities.
In the wake of the latest disaster in Hiroshima, the Abe administration will reportedly take steps to amend the law to simplify the process of local governments’ designating risky areas. The central government also needs to consider other measures to help local authorities speed up their efforts to highlight disaster risks.
On Tuesday, a government research panel disclosed its estimates of the maximum heights of tsunamis that could hit the Sea of Japan coasts — areas where research on tsunami and the efforts by municipalities to defend their communities from them have been lagging compared with the areas along the Pacific coasts.
While the estimated scale of the tsunamis are smaller than the ones that devastated the Pacific coastal areas of Tohoku in the 2011 Great East Japan Earthquake, and smaller than any tsunami anticipated after a big quake along the Nankai Trough, many parts of the Sea of Japan coastlines are still deemed vulnerable to tsunamis as high as 10 to 20 meters, including the southwestern coastlines of Hokkaido, where the maximum height of a tsunami is estimated at 23 meters.
The panel warns that tsunamis along the Sea of Japan coast could be larger even though the anticipated quakes that could hit the areas may be smaller than in Pacific coastal areas, and that they could hit the coastlines more quickly after the quakes. Prefectures and municipalities in the Sea of Japan coastlines are expected to use the tsunami-related data to review and beef up their defense against tsunami disasters.
Efforts to defend people against natural disasters require massive work in a variety of fields at both national and local levels. To take the most efficient anti-disaster steps under the tight budgetary constraints, the central and local governments need to work together to set priorities and allocate the limited resources to meet the most pressing needs.