Stone Environmental developed a tool to assess and reduce phosphorus entering Missisquoi Bay. The project began in 2022 in partnership with the University of Vermont and Québec-based organizations Research and Development Institute for the Agri-Environment (IRDA) and Organisme de Bassin Versant de la Baie Missisquoi (OBVBM). This binational assessment lays the foundation for harmonized phosphorus-reduction efforts on both sides of the US-Canada border.
In 2017, the US and Canadian governments asked the International Joint Commission to review information on reducing nutrient loading and harmful algal blooms in the Missisquoi Bay. The need for a mass balance model emerged from that review, and the Lake Champlain Basin Program awarded funds to Stone Environmental to carry out the project.
Mass balance models account for material entering and leaving a system. The Missisquoi Bay is fed by the Missisquoi, Pike, and Rock Rivers, all of which are monitored on an ongoing basis—meaning that researchers have a good understanding of phosphorus flows into the bay. Once present, phosphorus takes several years to leave the bay. Understanding the movement of phosphorus through the system is critical to supporting actions on the landscape that can reduce phosphorus entering the bay in the first place.
The new mass balance analysis will be used by the LCBP and other resource management partners to prioritize phosphorus-reduction projects. The binational approach to the study supports international coordination around managing cyanobacteria blooms in the bay—a water body shared and valued by residents of both the US and Canada.
Learn more about this project from the International Joint Commission.