Learning from natural disasters

People listed as missing after last week’s flooding of the Kinugawa River in Joso, Ibaraki Prefecture have been located alive. The next priority will be reconstructing the breached riverbank, pumping out water from the inundated areas, cleaning up the debris and restoring lifelines such as power and water supplies for local residents. Also important will be a review of the actions taken by the local administrators as well as residents to protect their lives — so that damage can be minimized in the event of similar disasters in the future.

In recent years, abnormal weather phenomena such as typhoons, torrential rainfall and twisters are happening in greater frequency and severity, which is often associated with the effects of global warning. We increasingly hear of severe weather described as “unprecedented” or the “heaviest in decades.” It most cases, both residents and officials of the municipalities in affected areas will have had no firsthand experience of a disaster of such magnitude.

Last week’s flooding was caused by record-breaking torrential rains that hit the Kanto and Tohoku regions. The last time the Kinugawa River, which flows through northern Kanto, breached its embankments was reportedly in 1949. Many of the residents as well as officials in the city, which is some 50 km from downtown Tokyo, may not have imagined that the levee along the river would fail on Thursday, even though the Meteorological Agency had issued special alert for heavy rain and flooding for broad areas including the city the previous afternoon.

Nearly five hours before the levee ruptured, the agency also issued a special warning for people in Ibaraki Prefecture to “take immediate actions” to protect their lives. Such a warning was introduced in 2013 after authorities determined that local residents were not adequately informed of the danger of flooding when torrential rains hit the Kii Peninsula in 2011 and northern Kyushu the following year, each of which resulted in large numbers of casualties. When dozens of people in mountainside residential area of the city of Hiroshima were killed in mudslides caused by downpours in nighttime hours in August last year, it was pointed out that local officials hesitated too long before they issued an evacuation advisory for the residents.

It has surfaced that the Joso municipal government issued an evacuation order for residents in areas along the river closest to the section where the bank ruptured roughly two hours after the levee breached, even though a similar order had been made hours earlier for people in nearby areas. The city has admitted error and confusion on its part. Evacuation advisory and order by the local authorities would have prodded more residents to flee, and it needs to be closely examined why the order was issued so late. But it also needs to be reviewed whether the residents themselves had been adequately prepared for safe evacuations in cases of emergencies.

Natural disasters result in extensive damage when the events go beyond what people expect based on their own experience. To protect ourselves against unprecedented disasters, we need to guard against the worst-case scenario and act promptly. Municipal government authorities should also learn from past examples and take adequate action, such as issuing evacuation orders while it’s still safe for the residents to evacuate — for example before the weather gets severe — not after the danger becomes imminent. How to safely evacuate elderly and disabled residents as well as small children in emergency situations must also be considered.

There will be limits to beefing up infrastructure to defend against natural disasters. Though necessary, there will be no end to efforts to make it robust enough to protect people in the event of disasters. Since the 2012 torrential rains in northern Kyushu, the Land, Infrastructure, Transport and Tourism Ministry has surveyed the conditions of levees along rivers under national government control that stretch a total of 13,390 km across the country, and determined that 16 percent of the embankments — or a stretch of 2,159 km — was vulnerable and needed work to make them stronger.

However, the progress of the work remains slow and there is not timetable for when it will be completed, due partly to the cutbacks on public works spending in recent years. In fact, work to strengthen the embankments along the Kinugawa River was under way just downstream from the site of last week’s disaster, with work at the site itself reportedly scheduled next. It will be difficult to eliminate the risk of flooding through infrastructure improvements.

The land ministry is urging more than 700 municipalities across Japan with the risk of flooding in their areas to devise a plan of action that should be taken by the local governments and residents to ensure a safe evacuation in advance of natural disasters, with specific timelines for what action needs to be taken by whom and when, by fiscal 2020. However, only about 200 municipalities have so far compiled such plans. In addition to speeding up the process, the municipalities need to constantly update their plans based on the lessons of others who have experienced disasters. Drills involving local residents will also be essential to see if the plans really work.

With the increasing severity of abnormal weather conditions, some disasters will be beyond the ability of a single municipality to handle. It is reportedly estimated that as many as 1.2 million people would be affected if the right bank of the Arakawa River in Tokyo’s Kita Ward ruptured. The national and prefectural governments will need to take on greater roles in devising and executing plans for protection and evacuation of people in the event of major disasters.