Dams are built to control water, they control much water stays in and stays out of the land, by lifting or shutting flood gates.
Dam are barriers that work as a water storage facility and create reservoirs that not only put an end to floods but provide water activities such as aquaculture, fishing, swimming, drinking and hydroelectricity.
A downside to dams is they can break if they are not looked after, not made properly or are holding too much water and unfortunately they cost millions to build.
Credits:
Created with images by Kdsphotos - "claerwen elan valley dam" • uvw916a - "Folsom Dam s490" • Me in ME - "Breaking Up Is So Hard To Do"