Odor & Air Emissions (CIG Project)

This project was a joint effort with the Wisconsin Department of Natural Resources (DNR), partially funded through a USDA Conservation Innovation Grant or CIG.  The project was a three year, $1.6 million demonstration of current technologies that focused on control of odor and concentrations of ammonia and hydrogen sulfide from agricultural operations. 

Four control technologies were studied on six different farms across the state:

  • anaerobic digesters
  • impermeable (HDPE) cover
  • permeable (geotextile) cover
  • solid separation with aeration 

Whenever possible, before and after comparisons were conducted on the same farm, however in the case of the digesters, comparisons were made with similar non-digester farms. 

Throughout the study, concentrations of ammonia (NH3) and hydrogen sulfide (H2S) were measured around the perimeter of manure storage lagoons, both before control practices were installed and again after the practices were in place.  Odors were measured using a field olfactometer downwind of the lagoons at 200 foot intervals.

The results of the study indicated:

  • The impermeable cover was highly effective at controlling odors (100% reduction), as well as NH3 and H2S concentrations. 
  • The permeable cover was fairly effective at controlling odors (70% reduction) and reducing NH3 and H2S concentrations. 
  • The combination of solid separation and aeration reduced odors, however not to a significant degree (25% reduction), while H2S concentrations were reduced and NH3 concentrations were increased. 
  • Anaerobic digesters had mixed results for odor control, as well as for their effect on NH3 and H2S concentrations.  One digester reduced odors slightly (15% reduction), whereas the other digester seemed to increase odors (15% increase) when compared to a similar non-digester farm.  H2S concentrations were reduced on both digester farms, however ammonia concentrations were elevated.

Direct questions on the project results to Steve Struss, project co-manager, 608-224-4629.

Project Report and Case Studies

Note: The case study files contain images, charts and diagrams, therefore the file sizes are extremely large.  A very limited number of printed copies are available. Contact Steve Struss at 608-224-4629 or send an email to for more information.

Final Report on Wisconsin’s Dairy and Livestock Odor and Air Emission Project, Sept. 2009 – 148 page PDF, 4.72 MB

Case Study 1: Anaerobic Digester, Waupaca County – 14 page PDF, 30 MB

Case Study 2: Impermeable Cover, Dunn County – 14 page PDF, 29 MB

Case Study 3.0: Permeable Lagoon Cover, Kewaunee County – 24 page PDF, 36 MB

Case Study 3.1: Sand Channels Contiguous to Permeable Lagoon Cover, Kewaunee County – 16 page PDF, 14 MB

Case Study 4: Solids Separation and Aeration, Monroe County – 19 page PDF, 27 MB

Case Study 5: Animal Feedlot, Clark County – 10 page PDF, 32 MB

Case Study 6.0: Manure Storage Lagoon, Manitowoc County – 10 page PDF, 28 MB

Case Study 6.1: Sand Channels Contiguous to Manure Storage Lagoon, Manitowoc County – 5 page PDF, 6 MB

Steering Committee

Secretary Rod Nilsestuen appointed a steering committee to ensure that the project maintains a strong connection to the agricultural industry and collaborates among key stakeholders.

Committee Members:

  • Kathy Pielsticker, Administrator, Agricultural Resource Management Division, DATCP
  • Ed Odgers, Agricultural Engineer, DATCP
  • Paul Zimmerman, Wisconsin Farm Bureau Federation
  • Laurie Fischer, Dairy Business Association
  • Al Koepke, Professional Dairy Producers of Wisconsin
  • Jordan Lamb, Wisconsin Pork Association and Wisconsin Cattlemen's Association
  • Andrew Hanson, Midwest Environmental Advocates
  • Al Shea, Administrator, Air and Waste Division, DNR
  • Eileen Pierce, Chief, Air Monitoring Section, DNR
  • Timm Johnson, Executive Director, Wisconsin Agricultural Stewardship Initiative
  • Duane Ford, Dean, Business, Industry, Life Sciences & Agriculture, UW Platteville
  • Tom Hunt, UW Platteville Pioneer Farm
  • Rick Klemme, Associate Dean, UW Extension, UW Madison
  • Dennis Frame, UW Discovery Farm
  • Tom Krapf, USDA NRCS

CIG Technical Team

The technical team consisted of individuals from state agencies, universities, agricultural. producer organizations, environmental groups, and the legal community.  Members were selected based on their working knowledge of Wisconsin agriculture as well as their scientific or specialized expertise.  The team assisted the agencies with the study design, farm selection, and test protocol.  Its input greatly assisted the project managers in planning the study and assured that it would produce valid, real-world results which producers could use.

CIG Technical Team Members

Mark Powell USDA-Agricultural Research Service
Laurie Fischer Dairy Business Association
Shelly Mayer Professional Dairy Producers of Wisconsin
Kim Brown Pokorny Professional Dairy Producers of Wisconsin
Kevin Griswald Professional Dairy Producers of Wisconsin
Al Koepke Professional Dairy Producers of Wisconsin
Pat Murphy Wisconsin NRCS
Duane Ford UW-Platteville
Tom Hunt UW-Platteville
Richard Klemme University of Wisconsin-CALS
Paul Zimmerman WI Farm Bureau Federation
Tom Krapf Natural Resources Conservation Service
Jordon Lamb DeWitt Ross & Stevens SC
Jamie Saul Midwest Environmental Advocates
Dennis Frame UW-Extension
Bryan Holmes UW-Extension
Fred Madison UW-Extension
Bob Wilson WI-DATCP
Al Shea Wisconsin Department of Natural Resources
Eileen Pierce Wisconsin Department of Natural Resources
David Grande Wisconsin Department of Natural Resources
Timm Johnson Wisconsin Agricultural Stewardship Initiative

Report editing and layout services provided by Doug Johnson, PhD., president, Environmental Intelligence Inc., St. Paul, MN

For more information contact Steve Struss,, 608-224-4629.