High Capacity Well Impacts on Wisconsin’s Lakes, Streams, and Wetlands
WI Green Fire, May 8, 2018
Revised June 3, 2020
Wells pump groundwater, which in Wisconsin is usually strongly connected to local lakes, streams, and wetlands. When groundwater is pumped, water levels in aquifers (the rock and soil that holds groundwater) drop, as do the levels of water in connected surface waters and the groundwater flows that support them. The effects of pumping are a matter of degree. A little pumping may make a small, barely perceptible impact with no apparent harms to public rights, fish, and wildlife, but larger amounts of pumping can be, and have been, devastating.
A high capacity well is defined in Wisconsin statutes as a well with a “… capacity to withdraw more than 100,000 gallons [of groundwater] per day…” or that “… together with all other wells on the same property, has a capacity of more than 100,000 gallons per day.”1 Wisconsin has some 7,700 wells capable of pumping more than 100,000 gallons per minute, and a total of nearly 13,000 statutory high capacity wells.2 Only a handful of high capacity wells were evaluated for impacts on lakes, streams, and wetlands prior to receiving regulatory approval.
High capacity well pumpage amounts to about 250 billion gallons per year (as reported for 2013, a fairly typical year), with roughly 40% of pumping attributable each to agricultural irrigation and municipal use, and lesser amounts attributable to industrial, stock watering, mining, and other uses.3
Wisconsin has been struggling since the 1950s to develop a framework that recognizes and manages pumping impacts, without success. Lately, courts have been asserting constitutional protections for surface waters from high capacity wells, while legislative and administrative actions seek to streamline processes for high capacity well owners.