Urbanization impacts on stream benthos of the Lake Simcoe Watershed

Session: Poster session

Raymond Bolton, Lake Simcoe Conservation, [email protected]
Robert Wilson, Lake Simcoe Conservation Authority, [email protected]
Kaitlin Cocks, Lake Simcoe Region Conservation Authority, [email protected]
Brian Ginn, Lake Simcoe Region Conservation Authority, [email protected]

Abstract

Human populations in the Lake Simcoe watershed are rapidly increasing and urban land use is quickly replacing rural pastureland and forested areas. Growing population densities increase environmental challenges for local ecosystems such as: nutrient/sediment loading, changes to riverine flow regimes, and stream morphology. The Lake Simcoe Region Conservation Authority has been monitoring more than 50 riverine sites within the Lake Simcoe basin using traditional benthic macroinvertebrate-based metrics (e.g. Hilsenhoff IBI, etc.) as outlined in the Conservation Ontario watershed reporting guidelines. This format has been successful in tracking biological responses to organic pollution but may be less effective at tracking trends related to inorganic compounds such as sodium chloride.

The use of winter de-icing salts, a necessary practice to ensure the safety of impermeable surfaces, has increased dissolved chloride rates by a mean of 0.81 mg/L per year in Lake Simcoe since 1972. Winter water quality sampling programs have shown that discrete measures in urban centers are now routinely surpassing both the chronic and acute Canadian guidelines. Our research investigates what effect chloride is having on aquatic biota in urban systems and are there better metrics for monitoring chloride and other urban emerging containments?       

1. Keyword
benthos

2. Keyword
assessments

3. Keyword
Lake Simcoe

4. Additional Keyword
Chloride

5. Additional Keyword
Road Salt