The Land of Water, the Linear Precipitation Zones of Ashihara no Nakatsukuni, and Annual Floods

In Japanese mythology, Japan is called Ashihara no Nakatsukuni (the Central Land of Reed Plains).
It was believed that this world consisted of three layers: upper, middle, and lower. The name means the reed plains located between the land of the gods, Takamagahara, and the afterlife, Yomi no Kuni. It is also sometimes called Toyoashihara no Nakatsukuni, meaning a land where reeds grow abundantly. Since reeds grow by the water, the land of reeds signifies a land of water. Japan is a land of water, overflowing with water.

When I go out from Tago no Ura and look, white snow has fallen on the high peak of Fuji.— Yamabe no Akahito, "Manyoshu"

When I pass through Tago no Ura and come out to a place with a good view, I can see Mount Fuji covered in pure white snow. (The original poem from the "Hyakunin Isshu")
For those who see Mount Fuji every day, it is just an ordinary mountain, but for a traveler, it is a "Wow, Fujiyama!" moment. Even those of us living in the provinces feel that "Wow" when we see Mount Fuji from the window of a Shinkansen. This poem captures that sense of wonder.

The same kind of wonder can be applied to the term "Ashihara no Nakatsukuni." For the Japanese, reeds are just ordinary plants by the water, and we don't even bother calling them by the name "reed." They are just waterside grass. However, for someone who has never seen reeds before, it is a sight they are seeing for the first time. A vast expanse of tall grass growing in clusters by the water is a scene that makes one want to say "Wow." To the person who named Japan "Ashihara no Nakatsukuni," Japan was a "land of reeds" and a "land of water." In other words, I imagine it was named by people who came from regions with little water.

This summer, we were struck by heavy rain. Even in Kobe, where there was less damage, warnings were issued repeatedly, and a heavy rain warning was in effect without interruption from 14:10 on August 13th to 11:32 on August 15th. Kyushu and other areas suffered significant damage.
A linear precipitation zone is a state where cumulonimbus clouds form one after another, causing rain to continue falling. I don't think that term existed in the past, but if you look at a rain cloud radar, the linear shape is clearly visible. The term "concentrated heavy rain" has existed for a long time, but it refers to rain falling beyond capacity. Global warming may be a factor, but Japan has been a land of water since the age of the gods.

My childhood home was near a river, so whenever the rainy season came, we would lift the tatami mats at least once a year as a flood countermeasure.
As for countermeasures, it just meant putting important things in high places so they wouldn't get wet and having the family evacuate to the second floor. We would leave the first floor in a state where it was okay if it got wet. There was nothing else we could do against nature.
If a levee broke upstream, we would feel relieved. That meant we were safe. We never knew where a levee would break. No particular region was favored. We lived on land where everyone was under the same conditions, never knowing when we might be flooded.
Luckily, since I was born, no nearby levees had broken. There was river improvement work, and the river was widened. Because of this, the river stopped breaking its banks, but my family home disappeared due to the improvement work. In the house that disappeared, there were clear traces left from when floods had come in the past. My grandparents, or perhaps people from even longer ago, had left those marks to pass down the history.

I never experienced a levee breach, but the bridge was washed away several times. It was a large wooden bridge that even buses crossed. It was destroyed by driftwood from upstream. When there is a flood, various things flow down the river. Since our house was in the lower reaches, a lot of things would wash down. The driftwood from the mountains wasn't just small branches; large trees would come floating down. During a flood, the river water itself is muddy, and you don't know what is in the water. Small trees were likely floating too, but you couldn't see anything in the murky water. Only the large trees would appear from the water, so they were easy to spot. Sometimes, objects that looked like houses would float by.
If the bridge didn't wash away, the driftwood would create a dam, and the levee would break. An enormous amount of debris would flow down. If that gets blocked, it becomes a massive quantity. A large dam is formed. If it were a sturdy concrete bridge that wouldn't be washed away by the muddy torrent, the levee next to the bridge would break. Or, a levee in a different location would break to try to reduce the volume of water in the river. No matter how you look at it, you cannot win against nature. We lived with the understanding that humans cannot defeat nature.

That is what the Japanese people should have been. That should have been the Eastern philosophy. Humans live within nature. Instead of the Western idea of destroying nature to create a comfortable environment for humans, the Japanese were supposed to have the consciousness of humans within nature.
I offer my sympathies to those who have suffered damage, but if you look at a hazard map, you must live with the understanding that there is no such thing as a safe region in our Japan.
I want to take a look at the hazard map once and re-examine my surroundings.