eli5: Why does there continue to be water in a river, even though it doesn’t rain all the time in the upper parts?

Question

eli5: Why does there continue to be water in a river, even though it doesn’t rain all the time in the upper parts?

In: 29

Answer 1

A lake, stream, or river isn’t a free standing body of water, it’s just the visible part of the MUCH larger water table. In all but arid areas there is groundwater some distance below the surface.