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The Water Cycle for Kids
Infiltration of surface water to groundwater

Here is a picture of a future hydrologist studying how water from the surface infiltrates into the ground to become groundwater. Fido assists by making depressions in the ground to demonstrate how low points in the ground will accumulate water, allowing it to recharge groundwater.

Many things influence how much and how fast water from the land surface infiltrates into the ground. What are some that you see in this picture?

• Amount of precipitation: How much water is falling (not much from the hose)? Is it falling in one spot or over the whole yard?
• Slope of the land: This yard is flat, so water will not runoff so easily. Thus it will be easier for the water to sink in straight down. On hilly land, less water tends to sink in, as it runs off more.
• Vegetation: Grass needs water to survive, and it gets water through its roots. The water from this hose saturates the ground close to the land surface, which makes this grass very happy.
• Heat and the sun: The sun causes water to evaporate back into the sky. The hotter and sunnier it is, the more water evaporates. The longer water stays on the surface, the more it evaporates.
• Animals: Fido will get thirsty running around in circles here and will go grab a drink from the hose soon.
• Humans: This young man is a huge part of the water cycle! People have totally transformed the world and the billions of people demand lots of water for their uses. The water cycle we describe in this Web site is mainly the "natural water cycle", the water cycle without human influence. A diagram of the true water cycle as it happens in today's world would have a lot of human influence on it.

Credit: Christina Ann Ross