Guerrilla Rainstorms: Where are the dangerous spots? How to "escape" for zero cost
[Shocking] Isn't the recent heavy rain getting a bit too serious?
The sky suddenly turns pitch black, and rain comes pouring down like someone tipped over a bucket... That's happening more often, right? Honestly, there are days that feel like a scene from a movie.
And you know, that sudden heavy rain, even if it's for a short time, is actually quite dangerous.
But it's okay. What I'm talking about today doesn't require money or tools; it's just about "where it's dangerous" and "how to escape." Just by knowing these two things, you and your children can stay on the much safer side.
I'll tell you first. For guerrilla rainstorms, it's "don't get close" and "escape to higher ground."
Before we get into the details, here is the most important part.
There are only two tips for staying safe during a guerrilla rainstorm: "don't get close to dangerous places" and "escape to higher ground early." If you remember just this, you've already passed.
The reason why sudden heavy rain is so dangerous is that when it pours down in a short time, the water doesn't have time to soak into the ground, and it flows into low-lying areas and pools up in an instant.
According to the Japan Meteorological Agency, about 30mm of rain per hour makes "roads look like rivers," and over 50mm is at the level where "it pours down like a waterfall, the surroundings look whitish, and visibility becomes poor"... You don't need to worry about the numbers. Just think, "Oh, it's raining so hard I can't see ahead," and consider that to be "pretty dangerous rain."
So, where exactly are those "dangerous places"? Let me talk about that.
Dangerous place #1: Underpasses, basements, and under railway bridges
The place you want to be most careful about is places that are lower than their surroundings.
Underpasses (those sunken roads where the road goes under train tracks or another road), underground passages, and under railway bridges. In places like these, all the water from the surrounding area flows in, so it pools up in no time.
What's more, the pooled water is murky, and you can't tell the depth just by looking. You might think, "It's just a little bit," and step in, only to find it's actually quite deep. On top of that, manhole covers might be dislodged underwater, or the edges of gutters might be hidden (JAF experiments have pointed this out, too).
So, if water is pooling in a low-lying area—don't enter. Don't get close. Take a detour. This is the best thing to do.
Dangerous place #2: Gutters, irrigation channels, and near rivers
Another one is near places where water flows. Gutters, irrigation channels, rivers, and around sluice gates.
During heavy rain, these places can flood all at once, making it impossible to tell where the road ends and the waterway begins. Accidents happen somewhere every year where someone gets too close, thinking they'll "just go check on it," and then slips and falls in.
Actually, the Ministry of Agriculture, Forestry and Fisheries clearly states, "Do not go to check on waterways until the heavy rain and strong winds have subsided." Even for professionals, it's too dangerous to get close. That's how serious it is.
So, let's make one promise with your children.
"On days with heavy rain, don't go to check on rivers or irrigation channels."
(Honestly, I understand the urge children have to go see when water is overflowing. But please, hold back. It's a promise.)
If you're driving: Don't drive into even a little bit of flooding
If you drive a car, please keep this in the back of your mind, too.
Cars are more vulnerable to water than you might think. According to JAF experiments, the limit for driving is "up to the bottom of the doors." If the water is deeper than that, water can get into the engine when you speed up, causing it to suddenly stop.
What's even scarier is that when the water reaches the height of the doors, the outside water pressure can make it impossible to open the doors. So, don't drive into flooded roads thinking "I can probably make it"; take a detour instead. If you do get stuck in the water, don't worry about the car—get out early. That is the golden rule.
(Even if you don't have a car, the same logic applies. If you're walking, it's even more important to avoid low-lying areas and the sides of water channels, and choose higher roads even if it means taking a longer way.)
The basic way to escape is "go up." But the best thing is to "know in advance"
When it's already too dangerous to go outside, move to an upper floor of a sturdy building. Just doing this can protect you from the water. This is called "vertical evacuation," but you don't need to remember the term. "If it gets dangerous, go up" is fine.
However, the strongest defense isn't thinking after you've panicked, but "knowing in advance".
Whether the place you live is "a place where you'll be safe if you escape to an upper floor" or "a place where you should evacuate to a different location early on." Actually, this is all written in your local government's hazard map. The Cabinet Office even says, "Please check this before a disaster happens."
I've summarized how to read them and where to get them in this article.
👉 https://note.com/bousai_taro/n/n9050e9ca8ffd
One step you can take today
You don't have to remember everything. Just do this today.
Mentally trace the roads you always take and see if there are any "low-lying areas, underground passages, or water channels."
The route from your house to the station or to daycare. If you realize even one thing like, "Oh, I should avoid that underpass during heavy rain," that's a huge win. Well done.
Finally
Knowing how to escape means you won't panic. And it doesn't cost a single yen.
I don't want to scare you. "Don't go near dangerous places, and if it gets dangerous, go up"—with just that, you and your children can stay on the safe side. I just want to share that with you.
Because—Disaster prevention is the art of kindness, you see.
Bousai Taro
P.S.
When it comes to heavy rain that you "know is coming," like a typhoon, preparing beforehand is effective. I've summarized some tips you can do in 5 minutes here, so please take a look at those as well.
👉 https://note.com/preview/nc3fdab82870c?prev_access_key=7877b4822aa4ceddb0ef79c2ceca6b2c