When it rains, rainwater soaks into the ground and puts pressure on the existing water in the ground, forcing some of it to move through natural cracks and openings in the rock until it reaches the surface and forms a(n) spring.An underground layer of permeable rock that is situated between two layers of impermeable rock so that water is trapped within it is called a(n) confined aquifer.
They are man made barriers, made of sand, to protect the coast from erosion from the incoming waves. They also help to control flooding from storm surge.
