Groundwater hydrographs

Groundwater hydrographs illustrate the historical record of aquifer water levels measured within a well. The example shown below illustrates two features of a hydrograph:

Ground water hydrograph.

1. A long term of record is important when evaluating water level trends. In the above example, an overall, long-term view shows that following a period of steady water levels, conditions changed, causing water levels to decline until again conditions changed, resulting in a water level rise.

2. Seasonal impacts on aquifers are often depicted by a hydrograph. In the above example, water levels drop during summer as demands on the aquifer increase. These demands include irrigation, lawn watering, car washing, and so forth.

Hydrographs and ground water level data for DNR Waters ground water level monitoring wells