What is the interaction between surface water and groundwater in a watershed?

Groundwater occasionally discharges into surface water and then, they flow together as a body of water in a watershed.

Explanation:

According to www.mbgnet.net A watershed describes an area of land that contains a common set of streams and rivers that all drain into a single larger body of water, such as a larger river, a lake or an ocean.

Therefore, when groundwater discharges into a body of surface water, for example a stream, the stream just like several other streams in a watershed would flow into a larger body of water.

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