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SLAMM and P-8 Models


This section is intended for use by highly technical professionals.

The following links are to the US Geological Survey Water Resources Division - Wisconsin District Office, for SLAMM (Source Loading and Management Model) and P-8 (Program for Predicting Polluting Particle Passage through Pits, Puddles and Ponds). Both SLAMM and P-8 are useful to predict pollutant loads and demonstrate compliance with the requirements stipulated in NR151 for urban areas.


WinSLAMM (Source Loading and Management Model for Windows) was developed to evaluate nonpoint source pollutant loadings in urban areas using small storm hydrology. The model determines the runoff from a series of normal rainfall events and calculates the pollutant loading created by these rainfall events. The user is also able to apply a series of control devices, such as infiltration/biofiltration, street sweeping, wet detention ponds, grass swales, porous pavement or catchbasins to determine how effectively these devices remove pollutants. DNR has guidance that applies to using WinSLAMM and other models, which is included in DNR's Post-Construction Modeling Guidance [PDF].

P-8 Urban Catchment Model

P-8 is a model for predicting the generation and transport of storm water runoff pollutants in urban watersheds. The model has been developed for use by engineers and planners in designing and evaluating runoff treatment schemes for existing or proposed urban developments. Predicted water quality components include suspended solids (five size fractions), total phosphorus, total Kjeldahl nitrogen, copper, lead, zinc, and total hydrocarbons. The model is used to examine the water quality implications of alternative treatment objectives. DNR has guidance that applies to using P8 and other models, which is included in DNR's Post-Construction Modeling Guidance [PDF].

See Recarga Model for information on modeling the performance of infiltration basins and bioretention devices.