Reservoir management could help prevent toxic algal blooms in Great Lakes
Managing reservoirs for water quality could be part of the solution to the growth of toxic algal blooms in the Great Lakes, especially Lake Erie
Managing reservoirs for water quality could be part of the solution to the growth of toxic algal blooms in the Great Lakes, especially Lake Erie
By Media RelationsManaging reservoirs for water quality, not just flood control, could be part of the solution to the growth of toxic algal blooms in the Great Lakes, especially Lake Erie, every summer.
In a major study involving data from Canada and the United States, researchers at the University of Waterloo identified reservoirs on streams and rivers as sources of food for algae at the worst possible time.
The culprit is dissolved phosphorus released from upstream reservoirs when warm lake water is ideal for the growth of algal blooms, which can cause illness and contaminate water supplies.
“Algae love dissolved phosphorus and when it arrives in the summer, it arrives exactly when they want it the most,” said Nandita Basu, a professor jointly appointed in civil and environmental engineering and environmental science at Waterloo.
Dissolved phosphorus, which comes primarily from fertilizer, is generally expected only at low levels in rivers and streams in summer following the peak snow-melt in spring.
But researchers found unusually high summer levels of dissolved phosphorus in areas with reservoirs, which are created by damming rivers and streams to hold water back to prevent flooding.
Basu, also a member of the Water Institute at Waterloo, said reservoirs store phosphorus that has been washed off farm fields in sediment.
In the warm summer months, that stored phosphorus is released from the sediment and increases dissolved phosphorus concentrations in water flowing downstream.
“Our work shows reservoirs can play a significant role,” said Basu, who analyzed data from more than 200 testing locations in Great Lakes watersheds. “They take in phosphorus that is attached to soil particles and release dissolved phosphorus that encourages more algae to grow.”
Basu said strategies to tackle the problem could include adding oxygen or chemicals to the water in reservoirs to prevent the conversion of phosphorus attached to soil into dissolved phosphorus.
The research was funded by Global Water Futures and led by Kimberly Van Meter, a former Waterloo postdoctoral fellow who is now a professor at the University of Illinois at Chicago. Former graduate student Shadman Chowdhury and current graduate student Danyka Byrnes also collaborated on the project.
A paper on their research, Biogeochemical Asynchrony: Ecosystem Drivers of Seasonal Concentration Regimes across the Great Lakes Basin, appears in the journal Limnology and Oceanography.
The gift comes from two Waterloo alumni with passion and drive to have transformative impact
University of Waterloo researchers discuss the challenges faced by researchers amid rising antagonism in climate science discourse
Waterloo announces winners of annual award for co-op students from each of the six faculties
The University of Waterloo acknowledges that much of our work takes place on the traditional territory of the Neutral, Anishinaabeg and Haudenosaunee peoples. Our main campus is situated on the Haldimand Tract, the land granted to the Six Nations that includes six miles on each side of the Grand River. Our active work toward reconciliation takes place across our campuses through research, learning, teaching, and community building, and is co-ordinated within the Office of Indigenous Relations.