Stevens Point Well 11 May be Partially to Blame for Hull Well Owners’ Plight- But it Also May Not

By Ray Schmidt, Portage County Water Quality Specialist

Recent media reporting in Portage County has brought attention to the possible effects of high capacity wells on nearby private well owners, and on lakes and streams.

The truth is anytime water is pumped out of the ground and used for crop irrigation or delivered to a municipal water system- then discharged to a stream following treatment- the water is no longer available at that location.

This becomes an issue when recharge from precipitation does not replace the amount of water being used. Groundwater is not unlimited, and in certain areas of the county those levels have dropped during hot, dry years and have not returned to normal- even during years of high rainfall such as in 2010 and 2011.

As groundwater levels drop, lake levels drop and stream flows decrease. Surface waters are really just the groundwater coming to the surface; since gravity is what moves water all over the earth, we’re seeing the effect of the decrease in our streams. It works this way underground, too- moving groundwater from higher levels towards discharges in lakes, streams, wetlands, springs- and even in high capacity wells.

As the levels inside the wells are lowered by pumping, groundwater rushes to fill the cones of depression surrounding each well and levels out the groundwater. When groundwater flows toward high capacity wells, it also flows away from other areas where it was previously available to private wells and surface waters.

According to the Department of Natural Resources, Portage County is the highest user of groundwater in the state for the second year in a row. The volume pumped for agricultural irrigation in 2012- 29 billion gallons- was nearly double that pumped in 2011 and dwarfs the amount of water pumped for non-agricultural uses in the county.

But that non-agricultural pumping has only increased slightly- up to 5.9 billion gallons in 2012 from 5.7 billion gallons in 2011.

Precipitation in 2012 was considerably below that of previous years, and along with extremely hot temperatures, water usage increased throughout the county. Groundwater levels dropped faster and farther during the peak period of irrigation than in 2011.

As a result, some streams throughout the county, including the Little Plover River, have dried up at certain times over recent years.

Property owners in the Town of Hull have needed to replace some of their shallow, sand point/driven point wells with deeper, drilled wells over the past few years. All of the water users in that area have had an impact on the groundwater levels, whether the water is pumped from private wells or from the new high capacity municipal well installed by the City of Stevens Point (well 11). The only difference is the amount of water being pumped.

Whether the municipal well pumping is responsible for lowering groundwater levels to a point where it causes the replacement of private wells is uncertain, but monitoring well reading from the area suggest that areas further from the municipal well are less likely to be adversely affected.