SWMM - Land Uses

Land uses are categories of development activities or land surface features assigned to Subcatchments. Examples of land use activities are residential, commercial, industrial and underdeveloped. Land surface features may include roofs, lawns, paved roads, undisturbed soils, etc. Land uses are used solely to account for spatial variation in Pollutant Buildup and leaching rates within of the Subcatchments.

The SWMM user has many options for defining land uses and assigning them to subcatchment areas. One approach is to assign a combination of land uses to each sub-Catchment, which results in all land uses within the sub-Catchment having the same permeable and impermeable characteristics. Another approach is to create subcatchments that have a single land use classification along with a distinct set of permeable and impermeable characteristics that reflect the classification.

The following processes can be defined for each land use category:

• Pollutant Buildup
• Pollutant Washoff
• Street Sweeping

A land use object has the following properties:

• Identification
  • Description - Use a friendly description when the item name is not enough
  • Name - name of the item
    Avoid names that are too long, or that contain the following characters: '*', '>', '<', '/', '\', '"', ':', ';', '|', '=', '`', '#', ',', '?'
  • Priority - Information about the current state of the item. It might be:
    • Neutral: no problem
    • Critical: Some issue that prevents the item from being calculated or used
• Street Cleaning
  • Sweeping Availability - Fraction of accumulation of all pollutants available for removal by scanning
  • Interval of Street Cleaning - Days between street sweeping within the land Use 0 for on sweeping
  • Last Cleanup - Number of days since the last scan at the start of the simulation
• SWMM
  • Pollutants - Table of Pollutant Buildup and leaching coefficients: