How does flooding actually happen? Can’t the water just keep moving

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I don’t get how houses/buildings can go under water?

In: 8

Not if there’s a lot of it. You’re underestimating how much water there actually is when it floods.

They usually happen when there is too much water for the rivers to handle. Happens often due to spring thaw of snow or heavy raining.

Maybe the river can handle 10m3 of water per second but due to heavy raining the flow is doubled. Suddenly the riverbed is just too small and the excess water needs to go somewhere – outside of the riverbed into the fields and houses.

Usually floods don’t happen because rain water can be absorbed by the ground as it falls. Floods happen when the ground can not absorb the water that is coming in. So water gathers above ground and becomes a moving wall of pain.

Remember, it’s not the rushing water that will kill you (unless you’re pulled under) it’s the debris in the water you’re smashing into (broken branches, cars, rocks, broken glass, ect) that will do deadly puncture and impact damage.

It does.

We just force it into small convenient channels.

Which get bigger when large volumes of water get dumped up stream.

Lots of variables here so I’ll try to separate parts I can best explain

1.Soil
Depending where you live, the type of soil you have varies, for example the soil where I live is very clay-like, so as a result during heavy rainfall small flooding can occur. Nothing major just small puddles in my yard. Though if you let’s say live in a valley, then the water has nowhere to go. Can’t go into the soil since it’s too thick, and if can’t go downhill so it’s stuck where it is and builds up which leads to flooding.

2. Sea level
Basic explanation of sea level is picture a flat line and that’s sea level or just 0, if you are above sea level, this means you are more elevated and less likely to experience flooding.

So for these two parts let’s make a little example, New Orleans often gets hit hard with tropical storms and causes extreme flooding. New Orleans is only 6′ above sea level, so off the bat not that high up, to add on New Orleans also has thick clay like soil so the water doesn’t seep into the ground it stays above. So since New Orleans is low the water can’t travel up hill, and the water can’t go into the ground it’s going to stay where it is and increase in depth.

A basic experiment of this is just getting a few containers and put them a lil bit higher then eachother, as if they were steps on a stair case. Then attacht a tube at the bottom of each except for the last one and have the tube go into the top of the previous container. If you fill the top container with water eventually all the water is going to make it’s way down, so the top container theoretically will have little to no water, while the bottom one will be full. *edit* This is just to explain water traveling down hill

Now for let’s say a river overflowing. Rivers are lower then the land it’s around, but if the water is equal in height around it, it’s going to spill over in simple terms. and keep spilling till it can’t anymore.