Groundwater is a vital resource for life in the Greater Madison Region. It is the source of all our public and private drinking water and provides the baseflow to our rivers and streams. Some water issues pose unique challenges for groundwater resource planning.
The following content will walk you through the specific issues facing groundwater in the Greater Madison Region. Use the tabs at the top to learn about issues affecting both the quantity and quality of the Greater Madison Region’s groundwater and to learn what you can do to help.
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Groundwater Maps
Wisconsin Water Quantity Data Viewer
Locations of USGS water quantity monitoring, groundwater protection features, wells, and springs.
National Ground-Water Monitoring Network
Water levels of wells throughout the region. It is part of the groundwater monitoring network overseen by the Wisconsin Geological & Natural History Survey.
Groundwater Documents
A report on private on-site wastewater treatment systems in Dane County. Onsite systems represent an important segment of the wastewater management and water quality planning programs in the region.
The systems, generally septic, serve about 11% of Dane County households. The primary concern regarding on-site wastewater systems is their effect on groundwater nitrate levels. Both agriculture and on-site wastewater treatment systems can contribute to these concentrations, but since wastewater systems are likely to be in close proximity to shallow private wells, they can pose a unique contamination threat to drinking water. Solutions include improving/replacing individual systems or providing centralized treatment, depending on scale.
On-site systems may fail because of inadequate design, unsuitable site conditions, or lack of proper maintenance. Current siting, design, construction, and maintenance standards, however, achieve minimal environmental impact compared to older systems, built under less stringent standards. A benefit of on-site systems is that they return groundwater to the source, whereas large wastewater treatment plants discharge to surface water. Current regulations and inspection programs generally ensure the level of maintenance and servicing of on-site systems necessary to reduce failures, continue proper functioning, and provide a long system life. Adequate technologies are available for on-site wastewater treatment systems to meet nitrate standards. These should be implemented to address nitrate pollution to groundwater.
- Governmental units responsible for the regulation of private on-site wastewater treatment systems should continue to maintain a rigorous inspection and enforcement program
- Local management and planning agencies should cooperate in investigating and developing cost-effective solutions for existing rural development experiencing on-site wastewater system problems and/or nitrate contamination issues
Large on-site wastewater systems and clusters of systems should be planned and evaluated to ensure that wells and water supplies can be protected from excessive nitrate levels - Holding tanks should continue to be used for wastewater disposal only in instances when adequate servicing and pumping can be assured, and when suitable disposal methods (well-regulated land disposal sites or wastewater treatment plants) are specifically available for receiving the wastes
Municipal wastewater treatment plants should include provisions for receiving and treating septage generated within a reasonable service area or distance - Explore innovative methods for improving waste disposal and groundwater quality through site design and new technologies
Land application sites for septage should be carefully located and designed to avoid groundwater contamination and should not be located in areas of extreme groundwater contamination risk or well protection zones. Existing sites located in these area should be monitored and subjected to stringent design and operating requirements - Dane County and/or local units of government should assume responsibility for, or participate in, the approval and inspection of land spreading sites for the disposal of septage
- Local units of government and Public Health Madison & Dane County should encourage all residents with private wells to have their water tested for nitrates, especially those with infants
- State and local funding for on-site wastewater management and septage disposal programs should be increased to adequate levels
A printed report and MODFLOW model to describe groundwater flow with 2010 typical withdrawals.
This can be used as a decision-support tool to:
- Aid in the siting of new groundwater wells
- Improve well-head protection plans for water utilities and municipalities
- Assess short and long-term responses to climate change
- Determine the impacts of land-use change on groundwater resources
- Evaluate well and groundwater quality problems
- Develop more detailed groundwater models for site-specific evaluations
A comprehensive analysis examining regional groundwater issues.
- Identify and characterize the location of groundwater and related physical resources (soils, geology, water table depth, springs, etc.)
- Evaluate, characterize and portray existing groundwater quality and quantity data for the county
- Inventory and assess existing and potential pollution sources in Dane County
- Describe and evaluate existing federal, state, and local programs that pertain to groundwater management
- Recommend groundwater protection strategies to improve groundwater management and prevent groundwater pollution
- Evaluate alternative management strategies for addressing groundwater quantity issues
- Provide regional water supply planning information for subsequent water supply planning purposes required under Wis. Stats. 281.348
- Create and share new products including Zone of Contribution and Groundwater Contamination Risk maps
- Introduce the use of groundwater budget indices and fish response curves to assess the sustainability of local water supply plans within a regional framework
- High nitrate-nitrogen levels (above the recommended drinking water standard) in a significant percentage (25%) of private wells in the county
- Increasing salt levels (concentrations) in municipal wells
- Organic chemical detections in some water supply wells near abandoned landfills and underground storage tanks
- A general lack of information on, and monitoring of, the possible effects of emerging pollutants (e.g., pharmaceuticals, personal care products, endocrine disrupters)
- Lack of rigorous enforcement in regulating land disposal of septage
- Reductions in ground and surface water levels due to high-capacity well water withdrawals