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Do you know how tree roots help prevent flooding in heavy rain, especially in low-lying areas like river plains? They help the ground to absorb more water from flash floods, reduce soil loss and property damage, and slow the flow. 

Trees intercept rainfall in their canopy, reducing the amount of rain that reaches the ground. The typical medium-sized tree can intercept as much as 2,380 gallons of rainfall per year!  A portion of this captured rainwater evaporates from tree surfaces.

When forest canopies are replaced with roads, parking lots, driveways, homes, patios, pools (also known as impervious surfaces) and even grass, watersheds and receiving waterways are immediately impacted.

How? On these manmade impervious surfaces, which collect solar heat in their dense masses, storm water from the land travels onto them instead of getting absorbed into the ground. As the storm water travels toward streams, it starts to collect pollutants and increase speed. In the process, the fast moving water changes the landscape, not only increasing the volume of water that goes to the stream, but also shortening the amount of time it takes water to get to the stream. This increased water flow leads to flooding, stream bank erosion, widening of streams, sediment deposited in streams, a loss of fish habitat, and decline in water quality. Not to mention the impact on those who rely on fishing as a livelihood. 

Tree canopies and root systems, on the other hand, help to absorb excess storm water, anchor the soil and prevent erosion.

| CLICK to learn what causes torrential downpours