A municipality relies on three pumping wells for drinking water supply. Understanding what area these wells draw from, what time frames are involved, and how much drawdown is induced can help identify threats and guide planning decisions that ensure drinking water quality and quantity.
To this end, a highly discretized 3 dimensional numerical groundwater flow model (representing layered geologic units, topography, recharge, surface water features etc) was developed. Various combinations of pumping rates were tested in the model, and for each model run particle tracking code was executed on the resultant simulated 3 dimensional velocity field. From this particle tracking output, an alpha shape algorithm was used to draw concave hull “envelopes” around the 2, 5 and 25 year capture zones. Simulated hydraulic head (i.e. water level) in the well was also recorded for each simulation to keep track of drawdown.
Bokeh is used to convey how well capture zones and drawdown change under changes in pumping rates:
Please note that the location on the map is fictionalized/“scrambled” - this is an illustrative example only