Groundwater modelling refers to the use of computer simulations to mimic the flow of groundwater and movement of dissolved contaminants in the subsurface. Models can be simple, one-dimensional calculations, 2-D representations or highly complex, layered 3-D systems. Groundwater modelling represents the "high-tech" side of hydrogeology.
Most modelling is performed using either analytical eng
ines (which are mostly 2-D) or more advanced, 3-D numerical engines (such as USGS Modflow). For both types, the model is configured to represent real world conditions such as soil layer properties, water table levels, streams and lakes. The model engine is then "run" and the output calibrated against actual field data.
Once the model represents the real world conditions, future scenarios can be simulated. For example, pumping future wells at various rates can be simulated to determine whether nearby wells or streams will be negatively affected. This is referred to as interference modelling. Groundwater models can also be used to predict the future path of a subsurface contaminant plume. One of the most important uses of groundwater modelling is to simulate the interaction between surface water and groundwater throughout a watershed area. Modelling is also utilized to identify vulnerable areas around community wells, which can then be protected to reduce threats to drinking water supplies.
Groundwater Modelling
