Southern Wisconsin is facing severe drought conditions, raising questions about its impact on our groundwater and wells. Survey hydrogeologists respond:
No. Wisconsin’s groundwater is not likely to dry up, especially in southern Wisconsin. However, groundwater levels could drop below the pump in a shallow well or in wells in fractured bedrock, such as granite. When this happens, the pump can burn out.
The groundwater level fluctuates based on the amount of water added (precipitation) and the amount removed (wells, springs, streams, and lakes). During dry periods, there is little rainfall to refill the groundwater, but the withdrawals continue. Not too surprisingly, during a drought, the groundwater level will drop. Areas with a history of low well yields, such as parts of north-central Wisconsin, are most susceptible to problems during droughts.
When water is pumped out of a well faster than water can flow back in to replace it, the groundwater level near the well can drop. The rate at which water flows into a well is controlled by the type of sediment or rock it’s flowing through. For example, water flows much more quickly through sand than it does through clay.
If groundwater levels near the well are lowered during pumping, a well may run dry even though the surrounding water table is still higher than the well pump.
Wells that begin to produce cloudy, muddy, or sandy water may be getting low. If your well begins to pump air, if the pump seems to run constantly, or if you notice surging or bubbles in the water the groundwater level might be dropping below the pump. This can damage the pump, so do not continue to run it dry.
If you have specific concerns about your well, your pump, or the water level, it is best to contact a licensed plumber, well driller, or pump installer who has the expertise to evaluate your well.
Each well in Wisconsin should have a well construction report listing details about well construction, well depth, and water depth. If you or a previous owner had a well drilled on your property, you may have a well construction report provided by the well driller.
Note, though, that pumps are rarely set at the bottom of a well and well construction reports do not report the depth to which the pump in your well was installed. This is the critical depth below which a drop in the water level will cause your well to run dry. If you do not have any records of the pump installation, and you start experiencing trouble with your well, you may need to contact a well installer.
Look up your well construction report (DNR database)
Request a copy of your well construction report (WGNHS service, fee charged).
For more information, visit the Wisconsin Department of Natural Resources, and the United States Geological Survey.