In Dane County, groundwater is the source for all public and domestic water supplies. It is an essential resource that we use and consume everyday. As efforts focus on water conservation, maintaining infrastructure, and improving efficiency, a growing population does not necessarily equate with larger groundwater withdrawals. On this page, compare groundwater to surface water withdrawals and explore trends in pubic water utility pumping over the past two decades.

On This Page

Photo Courtesy of EPA

Water Use

Take a look at how groundwater and surface water has been used over the past 40 years. Hover over a bar segment to see the amount of water used under each category. Select categories on and off to change display. These amounts include water pumped by both public and private wells.

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Data Source: Wisconsin Water Science Center USGS, updated April 2018. Learn more about USGS water use data and categories here. Download similar county data here.

How big is one million gallons?

A cube 51.1 feet long on each side. In 2015, Dane County used 60 million gallons of groundwater per day. That is the equivalent of an acre covered with 184 feet of water, everyday! This is also the equivalent of pumping about 75% of Lake Monona's water or the volume of two Lake Waubesas every year. 51% of Dane County's 2015 groundwater withdrawal was for domestic use.

Wisconsin relies heavily on groundwater resources. See more information from the Wisconsin DNR regarding withdrawals across the state, both from surface and groundwater. In 2017, Dane County had the second largest groundwater withdrawals of all Wisconsin counties (Portage County had the largest).

Public Utilities

Over the past 20 years, groundwater pumped by public utilities in Dane County has decreased even as population has increased. Madison Water Utility is the largest utility in the county and accounts for about 60% of public utility withdrawals. Sun Prairie, Middleton, and Fitchburg are the next largest utilities, each comprising about 5% of total public utility pumping in the region. Public water utilities track the amount of water that is pumped, sold to customers, used for non-revenue purposes (such as flushing water mains or fire fighting), and lost between pumping and delivery. Use the figures below to see how each utility compares to the regional total.

  • The top graph shows total regional public utility withdrawals from 1997 - 2017. The bottom two graphs only show information for the selected year.
  • Click on a municipality to see relevant data highlighted on each graph.

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Data Source: Public water utility pumping data is available through the Public Service Commission of Wisconsin. Population data is based on census data and CARPC estimates.

The amount of water pumped per person (per capita pumping) has decreased over time for the region as a whole. Decreases in per capita pumping can be linked to smaller non domestic uses (such as decreased industrial use), conservation and improved efficiency efforts, and infrastructure upgrades that reduce losses. Follow these conservation tips to reduce per capita use in your home.

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Data Source: Public water utility pumping data is available through the Public Service Commission of Wisconsin. Population data is based on census data and CARPC estimates.

As the regional population continues to rise, protecting and maintaining our groundwater resources is vital. It is important that we pump only what is needed and that pumped water is used productively. For some public utilities, more than 10% of the water pumped annually is lost. Efforts to reduce this loss means that pumped water is used more efficiently and that utilities can reduce pumping and conserve energy. Maintaining, upgrading, and investing in water delivery infrastructure is important for reducing loss. This figure shows the relationship between total pumping and population for each municipality over the past 20 years. Additionally, it shows how reported non-revenue, lost, and sold water vary year to year.

  • Click a municipality on the map to change the graphs
  • Draw a circle around multiple points to compare different municipalities

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Data Source: Public water utility pumping data is available through the Public Service Commission of Wisconsin. Population data is based on census data and CARPC estimates.

No matter whether your domestic water comes from a private well or public utility, you depend on groundwater everyday. Ensuring the quality and quantity of this groundwater into the future will play a vital role in maintaining this region as a desirable place to live and work.