Determining the Relative Contribution from Snowmobiles to an Acid Pulse Effect in the Watershed of the Haliburton Forest

Determining the Relative Contribution from Snowmobiles to an Acid Pulse Effect in the Watershed of the Haliburton Forest

Crowe, Erin

Haliburton Forest and Wildlife Preserve Ltd
Host contact: Bisset, Jody

Sager, Eric
Department: Environmental and Resource Science/Studies

TP-536

2004

U-Links Office and online

Haliburton County

Report addresses concerns of staff at Haliburton Forest regarding the environmental impacts of snowmobiling.

Episodic acidification events have been found to occur in fresh water lakes throughout North-eastern Cananda and the United States. In Ontario specifically, these events occur north of the Precambrian Shields southern boundary in a region that contains the Haliburton Forest and Wildlife Reserve Ltd. The determination of timing of specific events is difficult because of the ubiquitous nature of the event itself. Modelling of hydrographs and the acid neutralizing capacity (ANC) of the surface water, is suggested by some researchers as a method of predicting timing and duration of these events.

The majority of policy created to deal with these episodic acidification events has been based on research concerning the deposition of anthropogenic sulfates and nitrates. However, this study suggests that point source emissions from snowmobiles can also contribute to sulfate concentrations in the snow pack that may elevate the intensity of the acidification events during the spring thaw. Critical loads were calculated for the study lakes in the Haliburton Forests and Wildlife Reserve Ltd. using the Steady-State Water Chemistry Model. From these calculations and the analysis of snow samples it was determined that current inputs of acidifying compounds have concentrations just below the critical limits for biota in the lakes. It is therefore suggested that the number of snowmobile trail passes sold per day remain at 100 and trails across lakes be limited where possible. It is also recommended that further study take place on an increased number of lakes to determine differences in acid sensitivity and critical loads, while monitoring of both deposition and point source emissions continue.

Trent University