The Minnesota Department of Health (MDH) recently released a public health white paper entitled Reuse of Stormwater and Rainwater in Minnesota: A Public Health Perspective.
Water reuse is defined in the paper as: “The collection, storage, treatment, and use of stormwater, wastewater, and subsurface water. Stormwater reuse is also called ‘capture and use.'” As population increases, our communities become more urbanized, irrigation increases, the climate changes, and industries grow, water reuse will be a progressively important part of managing our water resources here in Minnesota.
Stormwater often contains pathogens that can make people sick. As MDH’s mission is “to protect, maintain and improve the health of all Minnesotans”, they evaluated the safety of selected Minnesota stormwater reuse systems.
From the Executive Summary of the paper, “This white paper provides guidance on what to consider from a public health perspective when approaching stormwater reuse in Minnesota. It gives an overview of potential health risks from stormwater reuse, presents a quantitative assessment of microbial risk with Minnesota data, and describes a risk-based framework that could be one approach to managing risks.”
Their evaluation demonstrated that pathogens in stormwater have the potential to infect people exposed to untreated stormwater when used for things like irrigation and indoor uses. However, those who design and operate these reuse systems can reduce these potential health risks. The end of the paper outlines recommendations to reduce these risks. Moving forward, MDH will participate in a workgroup that will develop actionable steps and hold conversations with key stakeholders about stormwater reuse, associated risks, and the potential need to manage water reuse in Minnesota. MDH acknowledges that there is a need for more research on pathogens and algal blooms in water reuse systems as well.