Doug Seaborn

In the west-central region of Ontario’s Nottawasaga Valley, urban development has been limited to estate homes and small housing subdivisions.
Our goal was to determine how land cover changes between 1978 and 2008 may have impacted the hydrologic behavior and water quality in the Mad Pine and Boyne rivers.
From 1978 to 2008, urban cover increased 68% in the Mad River, 80% in the Pine River and 109% in the Boyne River watersheds. By 2008, urban cover comprised 3% of the Mad, 6% of the Pine and 9% of the Boyne watersheds.
The analysis on streamflow data showed no significant trend in any of the rivers. Chloride levels increased significantly in each of the three rivers, while phosphorus levels declined. These findings are of interest because previous investigations suggest that elevated levels of chloride are not observed until urban land cover reaches 10 percent or more across the watershed.