once in the soil some is used by plants and also evaporates back into the atmosphere.some rain will also move downhill.this is known as runoff.how much and how fast run off occurs,depends on how much rain falls as well as where it lands.for instance a natural forest can hold large amounts of water and will slow the runoff allowing more water to soak into the ground.in areas of cleared forest or plantations,water runoff is faster and so less water is able to soak into the ground.in times of heavy rain there can be an increased threat of flooding when areas of natural forest are cleared and water runoff increases.obviously most rivers don't run dry as soon as the rain stops.