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GCC Report to the Legislature

The GCC identifies its recommendations for future groundwater protection and management. These recommendations include top priorities of immediate concern and ongoing efforts that require continued support.

Priority recommendations

Set new and revised health-based groundwater standard recommendations that are imperative for protecting public health and the environment.

Groundwater standards are imperative for protecting public health and the environment from PFAS, nitrate and other contaminants.
Groundwater standards are imperative for protecting
public health and the environment from PFAS, nitrate
and other contamination.

Wisconsin has a long and proud history of groundwater protection. Wisconsin’s groundwater law adopted in 1983 is held up as one of the nation’s model environmental laws in part because of its robust, science-based process for protecting the quality of our groundwater and public health. For 40 years, the groundwater law has guided the rule-making process that DNR and DHS follow, ensuring a scientifically rigorous review of available technical information and clarity on how recommended groundwater standards are selected.

The last time DNR and DHS were allowed to make revisions or additions to groundwater standards was 2009. Since 2019, DHS has provided DNR with two sets of recommendations (Cycle 10 and Cycle 11) based on state regulatory program needs for 47 new or revised groundwater standards. These include standards for pesticides, per- and polyfluoroalkyl substances (PFAS), metals, volatile organic compounds (VOCs) and bacteria. However, in 2022 the Natural Resources Board (NRB) ended rulemaking before sending the rule package to the legislature which would have set standards for the 26 Cycle 10 recommendations. As a result rulemaking was paused on the Cycle 11 PFAS and pesticides. While a NR 140 rule change setting new standard for e. coli and a revision in how total coliform is handled were successfully concluded in 2023, the backlog of needed standards and revisions continues to grow.

The GCC recommends the following action:

  • Allow DNR and DHS to finish rule-making that protects groundwater.
    • Forty-six NR 140 groundwater standards, first identified in 2019 and 2020, remain unaddressed.
    • A total 36 new numerical standards remain to be addressed, 18 PFAS, 16 pesticides and two metals.
    • Additionally, a total of 10 metals and VOCs have updated human-health information requiring a review of their existing standards.
    • Without these needed new and revised numerical health-based standards, groundwater regulatory programs remain unable to protect the public health of Wisconsin residents.

Implement practices that protect groundwater from nitrate, pesticides and other agricultural contaminants.

Nitrate and Land Cover in Wisconsin
Map of Estimated Percentage of Private Wells
over Nitrate Standard by County with Land Cover
(Jan. 2022 - June 2023).

Nitrate that approaches and exceeds unsafe levels in drinking water is one of the top drinking water contaminants in Wisconsin and poses known health risks. In addition, pesticides are estimated to be present in over 40% of private drinking water wells in Wisconsin. Areas of the state with a higher intensity of agriculture generally have higher frequencies of detections of pesticides and nitrate. 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.

GCC member agencies have been and continue to work on multiple initiatives related to reducing the risk of high nitrate and pesticides levels in groundwater (see groundwater management sections – DNR, DATCP, UWS, WGNHS) but the problem still persists.

The GCC recommends the following actions:

  • Make safe drinking water and protection of public health the top implementation priority for the state’s interagency Nutrient Reduction Strategy.
  • Create an online mapping tool to optimize targeting conservation practices where elevated nitrate in wells is present.
  • Assess soil type specific nitrogen crop application rates and cropping best management practices to minimize nitrogen losses to groundwater and encourage their use.
  • Develop educational materials and a broad outreach plan for farmers, nutrient management planners and agricultural industry stakeholders that identifies and encourages specific alternate cropping and nutrient management practices to minimize nitrogen losses to groundwater.
  • Create and staff a source water protection program (modeled on surrounding states) to better prevent drinking water contamination from occurring and provide support in areas impacted by groundwater contamination.
  • Develop surface water nitrogen numerical criteria to address nitrate alongside phosphorus within existing watershed based nonpoint pollution mitigation infrastructure.
  • Incorporate nitrogen budgeting and nitrate leaching potential into nutrient management practice standards and existing nutrient management tools.
  • Support collaborative interagency and producer involved development of Groundwater & Nitrogen Fertilizer Decision Support Tools.
    • To advance this complex technical and social challenge and make progress in reducing ongoing nitrate impacts to groundwater, the current project development partnership seeks to expand, as there is a need to incorporate additional multi-disciplinary contributions from researchers, agricultural producers, and software developers.
  • Revamp, fund and enforce nutrient management planning.
  • Continue groundwater monitoring to continue assessing known problem areas and identify new emerging areas of concern.
  • Expand the well compensation program.
    • GCC would like to see long-term funding secured for well owners to fix their wells. The short-term repurposing of federal dollars to well compensation was a welcome step. The funding provided $10 million in financial assistance to well owners to address contamination in their wells by awarding grants for the replacement, reconstruction, treatment or abandonment of their well. This program should be made permanent utilizing state funding.
  • Provide permanent funding to test private wells.
    • Only one third of private well owners have ever had their water tested for nitrate, the state’s most common contaminant exceeding human health standards (an estimated 10% or more, of private wells exceed the standard for nitrate-N).
  • Expand regulation of nitrogen losses to groundwater to all farms, not just CAFOs.
  • Further develop health standards and laboratory methods to keep pace with the evolving use of agricultural chemicals to ensure continued agricultural success that is so crucial for our state’s economy is balanced with the protection of groundwater and human health.

Address public health and environmental concerns regarding PFAS.

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

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.

The GCC recommends the following actions:

  • Implement groundwater enforcement standards for two PFAS, PFOA and PFOS.
  • Pursue development of additional groundwater enforcement standards for 19 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 media.
  • Develop benchmarks for PFAS in other media 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.

Ongoing recommendations

Without ongoing attention to the following needs, Wisconsin cannot address the priority recommendations or begin to understand emerging issues.

Evaluate the occurrence of viruses and other pathogens in groundwater and develop appropriate response tools.

Health Warning for contaminated water
Pathogenic microorganisms in drinking water can
make people very sick and can result in death.

Viruses and other microbial pathogens have been found in municipal and private wells, challenging previous assumptions about their persistence and transport.

The GCC recommends the following actions:

  • Continue to monitor and assess our understanding of pathogens in groundwater, in particular, where and when they pose threats to human health.
  • Work with partners to increase awareness of waste disposal choices, their risks and costs.
  • Improve best practices for well construction to minimize exposure to contaminated groundwater. Both agricultural manure sources and poorly constructed and maintained septic systems are potential threats to public health.

Support the sustainable management of groundwater quantity.

Water sensor level
GCC agencies monitor water levels in the state to
ensure sustainable water supply for human
consumption, healthy ecosystems and economic
growth; and to support sound resource management

We must ensure that water is available to be used in Wisconsin. This will protect and improve our health, economy and environment now and into the future.

The GCC recommends the following actions:

  • Continue to inventory information on the location, quantity and uses of the state’s groundwater.
  • Support targeted monitoring and modeling of the impact of groundwater withdrawals on other waters of the state.
  • Identify and evaluate options for areas with limited groundwater resources.
  • Advance research relating to changes in land-use development patterns and the resulting increase in groundwater use and changes to recharge.

Continue to catalog Wisconsin's groundwater resources.

Measuring the streamflow at Highland Big Springs in Iowa County.
Measuring the streamflow at Highland Big Springs
in Iowa County. © DNR.

Management and protection of Wisconsin’s groundwater resources requires publicly accessible, up-to-date data in order to foster informed decisions, not only on state policy matters but also for sound business decisions on siting or technology investments.

The GCC recommends the following actions:

  • Continue to collect, catalog, share and interpret new data about Wisconsin’s groundwater so that it can be used by health care providers, people seeking business locations, homeowners and local governments.
  • Share data about groundwater and groundwater vulnerabilities in accessible formats.

Evaluate the impacts of climate change on Wisconsin’s groundwater.

Elevated groundwater levels resulting in high lake levels at Fish Lake, a seepage lake near Hancock, WI.
Elevated groundwater levels resulting in high lake
levels at Fish Lake, a seepage lake near Hancock,
WI. © DNR.

Climate change is increasing the frequency and severity of weather patterns that produce unprecedented flooding or drought conditions. Severe flooding can affect groundwater quality, wells and water system operations. Additionally, land and water use patterns may also change and affect the groundwater supply. These may include biological or chemical contamination issues, or an increased demand for groundwater by agricultural, municipal, and commercial users.

Public drinking water supplies as well as water-dependent industries need reliable estimates of these impacts in order to develop practical emergency response and adaptation strategies.

The GCC recommends the following actions:

  • Continue work to determine the range of possible climates in Wisconsin’s future.
  • Research to help identify the feedback mechanisms between climate and groundwater to fully characterize possible changes to Wisconsin’s groundwater resource. This research will help identify both flood and drought response and long-term management strategies for Wisconsin’s groundwater supply.

Support applied groundwater research in Wisconsin.

Groundwater monitoring equipment
WGNHS hydrogeologists Grace Graham and Pete
Chase installing monitoring equipment in Door County.
© Maureen Muldoon)

Wisconsin is recognized as a national leader in groundwater research, which is appropriate given how uniquely important this resource is for public health, the economy and the environment in this state. For example, Wisconsin, leads the nation in the number of public water systems that rely on groundwater (more than 11,000). Over 97% of agricultural irrigation water and more than one third of the water used for commercial and industrial purposes come from groundwater supplies. And, many ecosystems in Wisconsin are strongly dependent on groundwater availability and groundwater quality.

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

Collectively, since its inception this annual joint solicitation has funded 501 groundwater research and monitoring projects and has helped establish Wisconsin as an international leader in groundwater research.

The GCC recommends the following action:

  • Restore the original authorized amounts of DNR and UW groundwater research funding.