Urban Land Cover Effects on Groundwater Chloride and Sodium Concentrations

Session: Poster session

Freddy Liu, Trent School of the Environment , [email protected]
Catherine Eimers, Trent University, [email protected]

Abstract

While many studies have evaluated the impacts of road salts on surface waters, there are relatively few evaluations of their impact on groundwater resources. This study used water quality data from over 2000 wells located across southern Ontario to evaluate spatial patterns in sodium and chloride, and their relationships between urban land cover (including transportation) surrounding the wells (2 km-radius buffer). Groundwater chemistry were evaluated at 75 representative wells across southern Ontario. Within the representative wells, chloride and sodium concentrations exceeded aesthetic notification levels (i.e. 250 mg/L Cl) in 10 % of the wells, and public health notification levels (i.e. 20 mg/L Na) in 48% of the wells. In addition, the maximum concentrations of Cl and Na in the wells were 407 and 315 mg/L, respectively. Preliminary results suggest that wells surrounded by higher percentages of urban land use and transportation are associated with higher concentrations of Cl^- and Na⁺. However, well depth and surficial geology appear to play a protective role against high Cl^- and Na⁺ concentrations in groundwater. 

1. Keyword
water quality

2. Keyword
environmental contaminants

3. Keyword
urbanization