Impacts of stormwater-induced road salt runoff on soil and water quality in urban greenspaces

Deicing, a necessary strategy for improving safety on motorways under freezing conditions, results in a concerning degree of salt accumulation in aquifers in cold-climate regions (Shaw, et al., 2012; Rivett et al., 2016). Shifts in weather patterns due to climate change warrant the development of new strategies to manage landscapes and infrastructure in response to new precipitation and temperature predictions. Many of these new strategies incorporate green infrastructure, which serves a vital role in managing stormwater runoff and mitigating the effects of flooding. However, urban greenspaces are sensitive ecosystems and susceptible to negative effects of contaminants carried in stormwater and snowmelt runoff. The proposed research will identify impacts of stormwater runoff and road salt on the soil and water quality of urban greenspaces. This will be achieved by installing a network of sensors in a natural (undeveloped) urban prairie site to obtain time-series data on stormwater-induced salt intrusion into the prairie. The long term goal is to develop high-resolution models to understand salt transport to surface water, groundwater, and soil in order to recommend strategies for the protection of urban greenspaces. The specific project aims are to: (1) quantify the impact of winter deicing salt applications at a highway and residential roads on soil, surface water, and groundwater quality in an urban prairie nature preserve, (2) quantify the effects of seasonality (winter storms and spring snowmelt) on salt delivery to the prairie, (3) model surface flow and infiltration of salt into soil and groundwater in the prairie.