Best Management Practices
"Best management practices" (BMPs) is a term used to describe different ways to keep pollutants out of runoff and to slow down high volumes of runoff.
Preventing pollution from entering water is much more affordable than cleaning polluted water! Educating state residents about how to prevent pollution from entering waterways is one best management practice. Laws that require people and businesses involved in earth disturbing activities - like construction and agriculture - to take steps to prevent erosion are another way to prevent stormwater pollution. There are also laws about litter, cleaning up after pets and dumping oil or other substances into storm drains.
Education / Laws
Education and laws are just two best management practice examples. Some BMPs are constructed to protect a certain area. Some are designed to slow down stormwater, others help reduce the pollutants already in it - there are also BMPs that do both of these things.
Detention ponds hold water so it infiltrates into the earth during rain events they fill up quickly after a rainstorm and allow solids like sediment and litter to settle at the pond bottom. Then, they release the water slowly. These ponds are one constructed BMP example. Green roofs, storm drain grates, filter strips, and permeable paving are other examples.