Why are bridges built so high?



I get it if its to avoid rivers overflowing but even then they’re higher than a 2 storey building. What’s the reason for building them like so?

In: Engineering

Things need to be built to deal with the absolutely worst possible outcome. If there’s an extreme flood, then the bridge needs to survive, and potentially still allow people to cross during an emergency.

Also, as someone else pointed out, so that large ships can go under them.

So boats and ships can go under safely?

Depends on the bridge and the river, to be honest.

Some bridges are so old that they were designed to permit mastheads to pass beneath them, sails and all, at high water.

Some are built to spam a shorter distance, or not make cars getting down the hill then back up it. There are a lot of factors.