Effects of Deicing Salts on Soil Infiltration Rate and Pollutant Uptake

Abstract

Winter snowmelt and stormwater runoff contain large concentrations of deicing salts. Past research has shown that NaCl has the potential to reduce the permeability of soils, defeating the purpose of green infrastructure. To understand the behavior of NaCl and its alternatives, our research compared three alternative deicing salts [sodium acetate (NaAc), calcium chloride (CaCl2), and calcium acetate (Ca(Ac)2)] to NaCl for their effects on infiltration, retention/release of metals, and fertility. The results suggest that chloride-based salts reduced the infiltration rate whereas the acetate-based salts had minimal impact. Calcium-based salts, especially CaCl, resulted in less copper uptake, compared to Na-based salts. After completing the infiltration tests, soils were tested for calcium, magnesium, potassium, pH, and phosphorus, total nitrogen (TN), total carbon (TC), sodium, and metals (copper and zinc). The soil test results confirmed that deicing salts resulted in less copper retention on the soil.