“The melted snow comes without any warning.”
The iconic image of Mt. Fuji and its snow cap is only possible because of the tremendous amount of snow that falls each winter, which then melts away with the timely arrival of spring. This melted snow becomes the water that is both the source of Fujiyoshida’s livelihood as well as its endangerment.
In the past, landslide-related disasters have occurred in Fujiyoshida due to the "meltwater" where the melted snow of Mt. Fuji rushes along with the sediment to the foot of the mountain. The Miyagawa River, which runs through the center of Fujiyoshida, is particularly affected.
The worst case was in March of 1961 when a large landslide filled the river and 130 houses along the Miyagawa River were buried underneath the fallen soil. The people who lived through that experience recount how they climbed their roofs and watched the overflowing river overtake their whole town without any heed or warning. But they learned from that experience and have since taken measures to prevent another meltwater-related landslide, like deepening the river to lower the water level and controlling erosion in areas towards the top of Mt. Fuji, and such tragedies have not occurred since then.
There are many houses near the Miyagawa River. Moreover, a small waterway leading to the Miyagawa runs under the houses. If you look under the houses nearby, you will find a house built on a small waterway. The homeowners probably think of that time every time spring comes.