Wisconsin’s Buried Treasure is Worth Protecting.

The GCC has funded over 30 years of groundwater research projects that have provided valuable information about Wisconsin's groundwater resources, helped evaluate existing programs, increased the knowledge of the movement of contaminants in the subsurface and developed new methods for groundwater evaluation and protection. 

•  Highlights of over 30 years of GCC-funded research  
•  GCC’s research and monitoring 

Wisconsin's reputation for  groundwater research  is largely due to the well-established joint solicitation process for groundwater research and monitoring projects. This approach streamlines proposal writing and the review process and improves communication among agencies and researchers. 

The GCC Report to the Legislature summarizes the operations and activities of the council, describes the state of the groundwater resource and its management and makes recommendations. The  Annual Report to the Legislature  is released each August and includes the  GCC's recommendations  for future groundwater protection and management. These recommendations include top priorities of immediate concern and ongoing efforts that require continued support.

For 40 years, the groundwater law has guided the rule-making process that the DNR and DHS follow, ensuring a scientifically rigorous review of available technical information and clarity on how recommended groundwater standards are selected.

Regrettably, the DNR has been unable to adopt the recommended groundwater standards due to rulemaking being prematurely halted when the economic impact analysis exceeded amounts set in law. As a result, the backlog of necessary standards and revisions continues to grow.  

It is important for the state to set standards for substances that are detected in groundwater and are shown to have a detrimental effect on human health. Adequate supplies of uncontaminated groundwater are crucial not only for the water we consume but also for our agricultural operations and breweries in Wisconsin.

Adopting groundwater standards are key for all council members in their continuing work to ensure every Wisconsinite has access to clean, safe drinking water. Clean drinking water in Wisconsin remains a public health priority for the council.

Allow the DNR and DHS to finish rule-making that protects groundwater.

Forty-six groundwater standards, first identified in 2019 and 2020, remain unaddressed. Thirty-eight new numerical standards also remain to be addressed - including 18 PFAS, 18 pesticides and two metals.

A total of 10 metals and volatile organic compounds (VOCS) also have updated human-health information requiring a review of their existing standards.

Without these new and revised numerical health-based standards, groundwater regulatory programs remain unable to protect the public health of Wisconsin residents.

• Nitrate has been found in wells in every county in Wisconsin.
• Nitrate is Wisconsin's most widespread groundwater contaminant, and the contamination of groundwater is increasing in extent and severity.
• Most nitrate in groundwater (about 90%) is due to agricultural inputs, including manure spreading and fertilizer application.
• Areas of the state with a higher intensity of agriculture generally have higher frequencies of nitrate detection. 
• The main source of pesticides in groundwater is agricultural herbicide and insecticide applications. 
• Pesticides are estimated to be present in approximately 43% of private drinking water wells in Wisconsin. 

Drinking water with high levels of nitrate is unsafe for everyone! It poses an acute risk to infants and women who are pregnant, a possible risk to the developing fetus during very early stages of pregnancy, and a chronic risk of serious disease in adults, such as thyroid disease and cancer. The health effects of pesticide exposure vary by substance. In Wisconsin, approximately 500 unique agricultural pesticides are used; of those, only about 30 have a groundwater quality standard.

Agencies should implement the strategies that lead to efficient use of nitrogen and careful or reduced use of pesticides in order to protect groundwater and drinking water sources.

Implementation of these practices should be supported with appropriate technical tools and incentives. 

Expand the statutory well compensation program. The GCC would like to see long-term funding secured for well owners to fix their wells.

Provide permanent funding to test private wells. Only one-third of private well owners have ever had their water tested for nitrate.

To see all of the specific GCC recommended actions,  read the recommendations section. 

For more information, read:

•  Nitrate in groundwater 
•  Pesticides in groundwater 

PFAS have been detected in both municipal and private drinking water sources in Wisconsin. 

Exposure to PFAS has been shown to have detrimental health effects, including the potential to cause cancer.  Scientists are still learning about the health effects that various PFAS can have on the body. Research suggests that high levels of certain PFAS may:

• Affect childhood development
• Decrease fertility in women
• Increase the risk of high blood pressure in pregnant women
• Increase cholesterol levels
• Increase the risk of thyroid disease
• Decrease antibody response to vaccines
• EPA research suggests that some PFAS may have the potential to cause cancer, but the topic requires further research

Learn more about health effects of PFAS on  DHS' website .

• Implement groundwater enforcement standards for PFAS.
• Pursue development of additional groundwater enforcement standards for 18 additional PFAS compounds detected in Wisconsin for which human health impacts have been identified.
• Continue to identify PFAS sources and their potential impacts to groundwater and other environmental resources.
• Develop benchmarks for PFAS in other resources such as surface water, biosolids and sludge to protect groundwater resources.
• Support the Wisconsin PFAS Action Council (WisPAC) in developing and coordinating statewide initiatives around PFAS.

For more information, read:

•  PFAS and groundwater 

Some areas of the state have limited groundwater supply due to aquifers with low water availability. Other areas of the state have an abundant groundwater supply but the number of wells drawing from the same aquifer coupled with a variable climate can result in impacts to groundwater-dependent natural resources.

Groundwater withdrawals along with variable climate may result in environmental harm including residential wells or streams drying up. Municipalities and businesses need water supplies, but in areas with limited availability it can be difficult to find the water that communities or businesses require. In certain areas, the density of wells and the existing harm on waters of the state restrict the ability for new applicants to obtain a water supply.

• Work with counties, municipalities, businesses and individuals to identify water sources to meet needs.
• Identify water conservation and efficiency measures to reduce demand in water-stressed areas.
• Develop a regional framework to manage water withdrawals, such as a water use district, to address water level impacts in the Central Sands Region.

For more information, view the  Groundwater Quantity section  of the report.