ANALYSIS OF THE UPSTREAM TO DOWNSTREAM IMPACTS OF ROAD DE-ICER APPLICATIONS ON WATER QUALITY IN NORTHERN MASSACHUSETTS

Freshwater salinization can have detrimental effects on aquatic ecosystems. Over the last several decades, freshwater salinity has increased in New England due to deposition of road de-icing salts directly into the environment during the winter, and other factors including urbanization. The purpose of this study is to evaluate seasonal trends in river salinity from an upstream to downstream gradient as well as to examine acute river responses to road de-icer applications. Six HOBO conductivity loggers were placed downstream of major roadway crossings along the Nashua River in North Central Massachusetts to determine the trends in salinity from upstream to downstream in the river. Continuous data collection began on October 1, 2020 with data points collected every 30 minutes. Soil samples were also collected in the fall and will be collected again in the winter to determine if roadside soils are impacted by de-icer applications. Soil sample extracts were collected from 1:1 soil:water solutions and analyzed for electrical conductivity and pH. We expect downstream river sampling locations to have higher salinity than upstream rural areas, likely due to increased inputs of stormwater runoff and road salt applications. We will report soil and water quality data collected during two seasons to examine the spatiotemporal effects of road de-icers on freshwater fluvial systems.