Geography
How Urbanization Alters Local Hydrological Cycles and Flash Flood Risks
Quick fact
In a natural landscape, about 50% of rainwater infiltrates the ground, but in a city with high impervious cover, that number drops to just 15%. This means more water floods streets and overwhelms drains, turning a normal storm into a flash flood.
Why this is interesting
Ever notice how city streets turn into rivers after a heavy rain?