Site	The site development scale highlights small-scale projects, such as single-family housing or small commercial developments.  Individual parcel owners manage small volumes of stormwater runoff, but collectively, these projects can have significant impacts on water quality.  Many of the Best Managment Practices (BMPs) classified as "site" can be done by individual property owners with little training.
Block	The BMPs at the block scale may require more space than is available at the site scale or may cost more to implement.  These BMPs are likely to be used in larger commercial, industrial, institutional, residential or civic developments.  As with the site scale, BMPs at the block scale are based on the best approach to capture and treat the stormwater as close as possible to where it initially falls.
Neighborhood	BMPs at the neighborhood scale take advantage of larger tracts of land, topographic features, soil conditions and water resources that are not available at the smaller scales.  Neighborhood BMPs may be constructed in civic open spaces, parks or street rights-of-way.  The BMPs also suggest appropriate development patterns for the neighborhood scale that provide stormwater treatment benefits.
City	Local policy makers and organizations must take the lead in promoting a cleaner, more environmentally-attractive method of reducing the water pollution that is generated in their communities.  City-scaled BMPs utilize city-wide intitiatives, programs, maintenance activities and resources to promote and support stormwater treatment goals.