Come to Texas and find out flooded out houses cars with water damage people drowning
What are the effects of floods?
Not watching Netflix in the basement 😡
Earth quakes and Hurricanes and mud slides.
On what? The the landscape of the land? Erosion would be the biggest concern. Such erosion can lead to a total new way a river flows, or can remove the side of a mountain. It can clear trees from the banks of a river.
On man-made structures, it can breech a dam, and/or wipe out houses and bridges. For the houses it leaves standing, but fills with water and mud, if not treated quickly and correctly, mold will take over and make the houses uninhabitable.