HR: 15:30h
AN: H14A-01    [Abstracts]
TI: The Fate of De-icing Salts in Stormwater Management Systems
AU: * Ballestero, T P
EM: tom.ballestero@unh.edu
AF: Stormwater Center, 238 Gregg Hall 35 Colovos Road University of New Hampshire, Durham, NH 03824 United States
AU: Roseen, R M
EM: Robert.Roseen@unh.edu
AF: Stormwater Center, 238 Gregg Hall 35 Colovos Road University of New Hampshire, Durham, NH 03824 United States
AU: Houle, J J
EM: James.Houle@unh.edu
AF: Stormwater Center, 238 Gregg Hall 35 Colovos Road University of New Hampshire, Durham, NH 03824 United States
AB: The traditional paradigm behind the design of stormwater management systems is to minimize the water quantity and water quality impacts resulting from land modification. The intent is to yield post-development hydrology similar to pre-development hydrology. The water quality aspect has been primarily focused on sediment removal, however, rarely are stormwater management systems designed for removal of de-icing salt. Chloride toxicity effects upon aquatic organisms resulting from snowmelt runoff are pronounced, routine, and problematic in northern climates. The capacity of current management strategies to treat chloride is in question. This paper explores the fate of de-icing salt through 13 different stormwater management systems. The systems include swales, retention pond, infiltration systems, bioretention systems, wetlands, manufactured devices, and porous asphalt. All systems exist at a field site and are delivered the same runoff (quantity and quality). The devices were designed and installed in accordance with existing drainage manual recommendations. None were designed for salt removal. As expected, devices with minimal water storage do not remove salt. Devices that do have significant amounts of storage do not remove salt, however the effluent concentrations are not as high as the influent concentrations: the peak influent salt concentration is attenuated similar to how the peak inflow discharge is attenuated by storage routing. The porous asphalt has displayed some remarkable characteristics. This surface has remained permeable throughout the winter, even though in addition to the de-icing chemicals, sand is applied. It appears that very little de-icing salt is needed on the surface, which has enormous economic and environmental implications.
DE: 1803 Anthropogenic effects
DE: 1860 Runoff and streamflow
DE: 1871 Surface water quality
SC: Hydrology [H]
MN: 2005 Joint Assembly