Impacts of Road Salting on Water Quality in Fractured Crystalline Bedrock

Abstract

Many rural communities depend on bedrock wells as a primary water source, which raises the issue as to whether increasing amounts of salt application are affecting bedrock water quality and to what degree. Through wellbore profiling, this study investigated changes in specific conductance in two crystalline bedrock wells at the University of Connecticut in Storrs, CT, from 2003 to 2016, with particular emphasis on the impacts of increased salt application with a change in deicing practices at the university after 2009. Hourly specific conductance measurements were collected in 2014 to determine how water source may affect wellbore concentrations seasonally. Chloride was found to be highly persistent in the bedrock, with concentrations consistently increasing from 2003 to 2016 despite year-to-year variations in salt application. A dramatic increase in chloride occurred in the wellbores in response to the change in deicing practices, with an immediate response in fractures having a direct connection to the overburden. In light of the long-term implications of road salting on subsurface chloride contamination, this study argues that consideration be given to deicing management strategies to reduce road salt contamination.

Freshwater salinization syndrome: from emerging global problem to managing risks

“…Underlying hydrogeology can influence the movement and residence of subsurface Clcontamination and transport of radionuclides. Chloride was highly persistent in fractured bedrock in Connecticut, USA and concentrations accumulated in groundwater over time due to road salts (Vitale et al 2017). In the Northeastern US, Na ?…”

Calibrating a model to 30 years of data to capture the accumulation of chloride from winter deicers in a shallow aquifer

“…Recent research has also utilized analytic approaches to estimate chloride applications in recharge based on land use (Betts et al, 2015) and has identified seasonal variability in the data (Rotaru et al, 2014). Vitale et al (2017) identified inflections in chloride increases through time and posited that these inflections indicate major changes in application rates or pathways for chloride to enter the aquifer. However, we are unaware of any attempt to model the transient forces behind chloride accumulation and variability.…”

Prediction of the Seasonal Changes of the Chloride Concentrations in Urban Water Reservoir

“…The increase in salinity of water characterized by the increase in chloride ions concentrations signals changes in the quality of the biotope and the risks of biocenosis settling such reservoirs [5][6][7][8][9][10][11][12][13][14][15].…”

“…In the periods of thaws, especially in early spring, when melting snow and ice cover of city streets flow into the tank substantial amounts of chloride ions. In this case the changes in chloride concentrations are seasonal [5][6][7][8][9][10][11][12][13][14][15]. Generally, in recent years we have seen an increase in the concentration of chloride ions in freshwater bodies of water around the world [5][6][7][8][9][10][11][12][13][14][15].…”