In general, liquid application should occur earlier than for solid chemicals. Therefore, accurate forecasts of storm arrival time are critical. Liquid chemicals are most often used for special purposes. In some states, city and state departments apply magnesium chloride to surfaces of long bridges. In some western states, departments treat roads several hours before snowfall to improve road friction during early stages of the storm.
Subsequent treatment is necessary to control chemical dilution.
Abrasives Sand and other abrasives DO NOT melt ice, nor do they significantly increase friction. Whether applied alone or in a mix, clean up costs and environmental affects can be significant. The most common reasons given for spreading abrasives are to please the public or local police. The publications page of this newsletter lists several publications available from the UNH T Center. Members of PW.NET can exchange information about what's working and what isn't.