Typhoon No. 8 may approach Tohoku and Kanto Koshin and land on the 27th tomorrow.

Regarding this typhoon, the Japan Meteorological Agency says that there is a risk that rainfall will increase near the center and on the north side, and that it will continue to rain, especially in the Tohoku region, and caution is required.


Disasters caused by heavy rain vary depending on the area, such as "floods" and "earth and sand disasters," but it is important to check the risks in your area in advance on a hazard map.

We have summarized the specific methods using "flood" as an example.

How do you view the "hazard map"?

The "hazard map" created by the local government can be used as a reference when deciding to evacuate.

First, check from your computer or smartphone.



The "Overlapping Hazard Map" published by the Ministry of Land, Infrastructure, Transport and Tourism is a site that allows you to overlay and display places at risk of floods and sediment-related disasters on a single map.

On the site, first select the "disaster type" you want to know.

Clicking on an icon such as a flood or landslide will display the location at risk of a disaster on the map.

Then enter the place you want to see in the space at the top of the screen and click the place you want to check in detail to understand the disaster risk of that place.

"Hazard map" checkpoint

If your home is within the expected inundation range, also check the inundation depth.

If the expected inundation depth is 3m or more, the one-story building will be submerged, and even if you are on the second floor, it will be inundated.



In addition, in the area designated as "Inundation area such as collapsed houses", the water level is high and the speed of the flowing water is high, so the entire building may be washed away.

Make sure in advance that your home is a place where you can stay in the event of heavy rain.

Past "flood" damage ...

Next is the characteristic of "flood".

The way a "flood" occurs and the timing of evacuation depends on the size of the river.

Small and medium-sized rivers “Rapid rise in water level”

Small and medium-sized rivers are narrow and the water level rises sharply.

In 2016, Typhoon No. 10 flooded the Omoto River in Iwaizumi Town, Iwate Prefecture, with the water level rising in a few hours and flooding the elderly facilities along the river, killing nine residents.



Also, in the mountains, there is a risk that not only water but also driftwood will damage the building.



If you are in a place where inundation is expected, it is necessary to take early measures such as starting the move for the elderly who take time to move when the local government issues an evacuation of the elderly.

Large river “Wide area is flooded for a long time”

Once a large river overflows, a large area is flooded for a long time.

In the heavy rains in the Kanto and Tohoku regions in 2015, one-third of Joso City in Ibaraki Prefecture was flooded by the flooding of the Kinugawa River, and it took 10 days for the water to drain.

Large river “The water level rises after the rain stops”

The water level may continue to rise even after the rain has stopped.

Ototoshi ・ In Typhoon No. 19 in 2019, flooding occurred one after another after the emergency warning for heavy rain was lifted, and flooding was confirmed 9 hours after the emergency warning was lifted in the upper reaches of the Abukuma River in Fukushima Prefecture.



Once you have evacuated, be sure to check the water level of the river and the evacuation information of the local government even if it stops raining before returning.

Be careful even in places not shown on the hazard map

On the other hand, there are many small and medium-sized rivers for which the hazard map does not yet show the assumption of inundation, and there is a risk of damage in these areas.

Even if the map does not show the risks, it is important for people living near or low in the river to be aware of their surroundings and local government information and move to a safer place.

Confirm before danger approaches

Information on hazard maps and evacuation can also be found on the NHK website "Your Weather / Disaster Prevention" and "NHK News / Disaster Prevention App".



You can also check the water level of the river on the website "River Disaster Prevention Information".



Understanding the risks of your own home in advance will lead to early evacuation. Please check once before the danger approaches.



▽ "Hazard map portal site of the Ministry of Land, Infrastructure, Transport and Tourism"


https://disaportal.gsi.go.jp/


▽ NHK "Your weather and disaster prevention"


https://www.nhk.or.jp/kishou-saigai/hazardmap/