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Back to designDeaigning Dams - Hydrologists

Laboratory model of spillways

A laboratory model of the spillways at a
dam showing how the water flows
over them

Engineering hydrologists, involved in the design of a dam, are interested in the quantity and movement of water at the site. They need to know how much rain and snow is likely to fall there, how much of it will soak into the ground and how it will move through the ground. With this knowledge they can work out the amount of water that would normally flow into the reservoir each year, and how big the reservoir needs to be to store it. They also estimate the size of the waves on the reservoir that would be caused by wind. This information helps determine the height of the dam.

They also have to consider the worst snow or rainfall that could possibly occur, and they design spillways to make sure that excess floodwater can be passed safely through the reservoir without overtopping the dam.