Milwaukee’s wastewater utility has been a pioneer in circular economy practices since 1926, transforming biosolids into valuable fertilizer and renewable energy, while aiming for ambitious carbon reduction goals by 2035.
- Milorganite fertilizer returns $11–$12 million annually to the city.
- Facility generates up to 85% of its electricity from biosolids.
- 2035 goals include 100% renewable energy and 90% carbon reduction.
What happened
Since 1926, Milwaukee’s sewerage district has converted biosolids from wastewater into Milorganite, an organic nitrogen fertilizer that provides a significant source of revenue while preventing waste from filling landfills. This practice predates the popular circular economy concept by nearly 100 years and reflects a long-standing commitment to sustainable waste management.
Today, the district runs eight digesters at its South Shore plant, which generate 80 to 85% of the facility’s electricity needs from these biosolids. The remaining biosolids continue to be used for fertilizer production. Partnerships with local breweries and food producers allow waste co-digestion, creating cost savings and boosting energy generation, highlighting the facility’s role as a sustainability innovator.
Why it feels good
MMSD’s approach exemplifies a successful cradle-to-cradle model, where waste products are not discarded but repurposed in a way that benefits both the environment and the community. This ongoing cycle provides economic benefits while reducing landfill dependence and greenhouse gas emissions.
The district’s deep-rooted culture of sustainability fosters collaboration with regional industries and forward-thinking partners. Their 2035 targets of 100% renewable energy use and a 90% reduction in carbon emissions compared to 2005 demonstrate a powerful long-term vision for climate responsibility, fostering optimism about the future of utilities as vital community anchor institutions.
What to enjoy or watch next
For those interested in learning more about innovative wastewater management and sustainability, Milwaukee’s model sets a compelling example of circular thinking in action. Exploring resources at mmsd.com offers insight into how wastewater utilities can transform challenges into opportunities for public good and environmental stewardship.
Listeners and readers who enjoy stories about impactful green innovations might follow similar utilities adopting co-digestion partnerships or investing in renewable energy from waste streams. Tracking progress toward ambitious carbon reduction and renewable goals in other cities could also provide hope and actionable ideas for a more sustainable planet.