Catchment-Defined and General Land Use Categories for Runoff and EMC Characterization – Best Management Practices for stormwater

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Overview

A catchment is a land area from which a volume of water can be discharged and at the point of discharge a BMP is possible.

The land use is characterized by all features within the catchment, thus a low-intensity commercial area includes parking, building, and vegetated cover crop. This low-density catchment can be furthered divided into a roof area catchment if there is a possibility of a BMP for the roof, as well as a parking/green space. 

A watershed is a surface area that is composed of one or more catchments.

GENERAL CATEGORY	DESCRIPTION
Low-Density Residential	Rural areas with lot sizes greater than 1 acre or less than one dwelling unit per acre; internal roadways associated with the homes are also included.
Single-Family Residential	Typical detached home community with lot sizes generally less than 1 acre and dwelling densities greater than one dwelling unit per acre; duplexes constructed on one-third to one- half acre lots are also included in this category; internal roadways associated with the homes are also included.
Multi-Family Residential	Residential land use consisting primarily of apartments, condominiums, and cluster-homes; internal roadways associated with the homes are also included.
Low-Intensity Commercial	Areas which receive only a moderate amount of traffic volume where cars are parked during the day for extended periods of time; these areas include universities, schools, professional office sites, and small shopping centers; internal roadways associated with the development are also included.
High-Intensity Commercial	Land use consisting of commercial areas with high levels of traffic volume and constant traffic moving in and out of the area; includes downtown areas, commercial sites, regional malls, and associated parking lots; internal roadways associated with the development are also included.
Industrial	Land uses include manufacturing, shipping and transportation services, sewage treatment facilities, water supply plants, and solid waste disposal; internal roadways associated with the development are also included.
Highway	Includes major road systems, such as interstate highways and major arteries and thoroughfares; roadway areas associated with residential, commercial, and industrial land use categories are already included in loading rates for these categories. .
Agriculture	Includes cattle, grazing, row crops, citrus, and related activities.
Open/Undeveloped	Includes open space, barren land, undeveloped land which may be occupied by native vegetation, rangeland, and power lines; this land does not include golf course areas which are heavily fertilized and managed; golf course areas have runoff characteristics most similar to single-family residential areas
Mining/ Extractive	Includes a wide variety of mining activities for resources such as phosphate, sand, gravel, clay, shell, etc. .
Wetlands*	Include a wide range of diverse wetland types, such as hardwood wetlands, cypress stands, grassed wetlands, freshwater marsh, and mixed wetland associations.
Open Water/ Lakes	Land use consists of open water and lakes, rivers, reservoirs, and other open waterbodies. For the BMPFast software, the runoff is zero (ET and infiltration = precipitation)