WMS:MODRAT Percent Impervious Land Use

To compute the Percent Impervious for each sub-basin of your MODRAT model, you must read in a land use data layer. Land use data is generally stored in a GIS, the best way to read it into WMS is though a Shapefile. To import land use data for use with MODRAT, create a Land Use Coverage, then import the polygon file and ensure that the Percent Impervious field (often called IMPERV_ by the LACDPW) is assigned to LA County Soil land use field of WMS. Once the land use data is present in WMS, you can compute and assign % impervious using the Map Attributes command from the MODRAT menu.

Related Topics

• Impervious Area
• Using GIS Data to Map Parameters
• Soil Number
• Rainfall Depth