Changes in water quality in an urban stream following the use of organically derived deicing products

Willow Brook receives runoff from Cooperstown, NY and flows into Otsego Lake, a phosphorus limited, mesotrophic waterbody. Between 1992 and 1998, the Village of Cooperstown’s winter road management policy included plowing and applying abrasives (particulate material intended to increase traction) mixed with enough salt to minimize clumping. Between 1998 and 2002, Ice Ban Magic and Magic Minus Zero, both organic deicers mixed with magnesium chloride, were applied experimentally in conjunction with abrasives and salt. During the winter of 2002/2003, road treatment consisted solely of applications of salt which had been treated with Magic Minus Zero. Precipitation-based monitoring on Willow Brook conducted between 1991 and 2003 revealed significant declines in the export of total phosphorus, despite elevated phosphorus levels in Ice Ban Magic and Magic Minus Zero, and suspended sediment as the volume of abrasives applied to roads was reduced. Chloride levels are increasing, however. The implicit trade-offs between potential pollutants and the cost of road management in cold climates are acknowledged for management of transportation safety .