Creating flood

Hi,
do anyone have an idea on how to make or create a flood passing through a valley?

Obvious option is to use the fluid simulator and just use an inflow object to throw a stream of water down the valley. You’ll probably want to do this on its own layer and make a lo-res dummy version of the valley to act as the fluid obstacle (don’t render it, obviously). This is a pretty time-consuming method and leaves you with a pretty high-poly water flow in the end though. What’s this for? How realistic does it need to look? How realistic does it need to move? How long do you have?

Thanks alot, its for a short animation on a boy trying to cross a wooden bridge and the water broke down the bridge, not to realistic and only for the flood coming and heating the bridge to be seen

I posted a starter filehere for flooding a city. Maybe it can get you going…?

Thanks very much.