The damage can be similar, but the cause is different.
Water damage is usually caused by water coming from something like a burst pipe, an overflowing toilet, a dishwasher that leaks all over the kitchen floor, or a roof that leaks after a hard rain.
Flood damage is caused by water coming from something like an overwhelmed levee that breaks, a clogged drainage system, a river or lake that overflows, or even just the ground being inundated with too much water after a torrential storm. Water seeping into your basement after heavy rain or winter runoff is usually also considered flood damage.
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