How does ground water relate to lakes or rivers? All lakes and rivers are replenished by groundwater.
When ground water reaches the surface it can form lakes or rivers.
Groundwater can affect the size of lakes and rivers.
Lakes and rivers produce groundwater.

When ground water reaches the surface it can form lakes or rivers.

Explanation:

Groundwater in valleys is often pushed under pressure by rainwater that falls on the nearby highlands. If the water table reaches the surface, a lake, a river, or a spring is formed. A spring in desert country is surrounded by plants that take advantage of the water supply, forming an oasis. Water now coming to the surface at oases in the Sahara Desert came from rain that fell on hills near the desert during the Middle Ages--eight hundred to one thousand years ago.

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meteorologists would compare a new weather map with one 24 h old to see how fast a front is moving.