Land use is an important consideration in low impact development and the implementation of green infrastructure. Some land uses are more easily obtained by municipalities, more conducive for retrofitting BMP projects and converting land to open space, and have more pervious areas than others. Publicly owned land is more easily obtained by municipalities than private land, for instance, and existing open space with sparse underground utilities and low imperviousness can more easily incorporate various types of regional BMP projects.
Also important to consider in BMP siting is the basic assumption that stormwater characteristics, particularly water quality, are a function of land use. This assumption is generally accepted because activities and site features – i.e., potential sources of stormwater contamination – are generally consistent within each land use category. Land use‐based events mean concentrations (EMCs) are often used to estimate runoff concentrations and loads. BMP placement is typically most effective when it occurs downstream of land uses that are heavily polluting.
The figure below presents the major land use categories within Los Angeles County.