Stormwater management is the effort to reduce runoff of rainwater or melted snow into streets, lawns and other sites and the improvement of water quality.
When stormwater is absorbed into the soil, it is filtered and ultimately replenishes aquifers or flows into streams and rivers. However, when heavy rainwater hits, ground saturated by water creates excess moisture that runs across the surface and into storm sewers and road ditches. This water often carries debris, chemicals, bacteria, eroded soil, and other pollutants, and carries them into streams, rivers, lakes, or wetlands.