• Siting and Land Use decisions
  • Pollution Control Practices

Appropriate nutrient management on farms is one way to reduce the risk of groundwater contamination. UW Extension has developed nutrient application guidelines for Wisconsin crops (available in print or free as a PDF).  The Department of Agriculture, Trade and Consumer Protection also helps farmers meet nutrient management requirements. DATCP tracks the status of nutrient management plans across the state. In 2018, 43% of Dane County's cropland had nutrient management plans. Organizations can apply for grants to help teach farmers how to develop nutrient management plans. There  is also a grant that directly supports producer-led watershed protection initiatives. Concentrated Animal Feeding Operations (CAFOs) require discharge permits for wastewater. The Wisconsin Department of Natural Resources issues permits and ensures that CAFOs comply with their nutrient management plans.


Private Septic Systems

The Department of Safety and Professional Services under SPS 383 Wis. Stats regulates private
septic systems. The private septic system program does the following:

-Establishes design standards and accepted waste management practices for private septic
- Establishes the criteria under which sanitary permits are issued to build private septic
systems, which discharge pollutants to waters of the state.
- Establishes soil site evaluation standards for placement of septic systems.

Photo Courtesy of: Madison Water Utility

On-Site Wastewater Treatment Systems

In 2013, CARPC published a report on Private On-Site Wastewater Treatment Systems Management. 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.

Report Recommendations

  • 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

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