Dr. William Taylor

Grand River under siege

When William Taylor wades into the Grand with his fly rod, he ponders the future of the Canadian Heritage River that flows through Waterloo Region. As a fisherman and a resident, his interest is more than academic. As a researcher, linking up with other researchers and with the Grand River Conservation Authority, he dips deep in search of answers.

The biology professor, who holds the Canada Research Chair in Limnology (the study of fresh water lakes, ponds and streams), is increasingly concerned about the impact of urban development and climate change on the river. 

How much stuff can we throw into it before driving it to the point where it no longer supports life?” Taylor asks himself. “Are we at the edge of pushing the river to the point where it can’t recover?”

To answer such big questions, he works with colleagues in biology, and in earth and environmental sciences, “one of the best groups of aquatic ecologists in Canada.” Taylor specializes in the study of nutrients, substances that support life. However, when nutrients are added in excess, they can damage an aquatic ecosystem.

While the human population and the volume of sewage discharge along the Grand is increasing, water levels are falling due to drier summers and more water taken out of the river for municipal uses, he explains. The result: discharge from sewage treatment plants is becoming less diluted.

Excess phosphorus and nitrogen — from lawn and agricultural fertilizers and from sewage treatment plants — stimulate the growth of plants and algae in the river, causing more drastic daily fluctuations in oxygen levels. When the amount of oxygen in the water falls too low at night, the survival of fish, as well as other kinds of animal life in the river, is threatened.

Taylor and his colleagues and students are studying the relationship between the nutrient levels and the daily oxygen cycle. The information they collect is being used by the Grand River Conservation Authority to help farmers and municipalities improve the health of the watershed.