Default Land Use and Soils

For land use and soils, WAM uses a hierarchically based configuration system that has the ability to precisely classify data, or to group similar features based on the level of classification used. WAM utilizes a sliding or dynamic classification scale, in that certain land use types are aggregated into a representative class that can parameterize all features within the group, while other features might be parameterized singularly. This is done to reduce the number of unique cells that are created to be simulated by BUCSHELL, speeding up model run times, but still achieving the desired level or source cell specificity required by a simulation's goals and objectives.

Both land use and soil types are grouped into similar categories depending on the source cell sub-model that will be used to simulate the daily flows and loads that are generated on that source cell. The Technical Manual covers the Selection of Source Cell Models. Different categories provide access to different parameter types specific to the source cell sub-model simulation process. For land use, categories are further separated into sub-categories which will further determine the available parameters. The Map Properties Section of the User Manual provides a detailed description of the land use categories, sub-categories and BMPs as well as the soil categories and the parameters that can be edited by each.

WAM has over sixty predefined land use sub-categories and available BMPs that have been parameterized to represent over 360 different FLUCCS types. 260 default WAM soil types are provided that represent over 450 different USDA SSURGO dataset compnames. The user can edit and select how this aggregation occurs. This is discussed in the two sub-sections Land Use and Soils.

If the land use and soil features that are being imported to WAM do not have corresponding WAM specific matches, those features will be automatically assigned to the land use category of "Initialization" and the soils category of "Area Not Defined". Once your land use and soils data is imported to a scenario and loaded into the ArcMap table of contents, the attribute tables for both land use and soil should be reviewed to check that a complete aggregation to WAM supported groups has occurred. If any "unrecognized" features exist, the Features Properties Editor can be used to either remap those unrecognized input types to existing WAM groups, or create a new distinct WAM group that characterizes that type. This is discussed in the two sub-sections; Land Use and Soils.