 winter storms snow and ice they can create big problems on highways accidents delays traffic jams every year highway agencies spend over a billion dollars on snow and ice removal and apply large quantities of chemicals and abrasives that lead to environmental pollution bridge corrosion and of course rust on your car we accept this to keep our roads passable and our driving safe but improved methods are clearly needed in 1987 the president signed a transportation bill creating the strategic highway research program a five-year effort to develop new methods and products in highway construction maintenance and safety one of the research areas of the program was snow and ice control an important product of this research was the development of anti-icing technology what is anti-icing generally speaking it is a snow and ice control strategy for important roads that must be kept open its goal is simple to prevent a strong bond between snow and ice and the pavement or between ice and bridge decks though several technologies could accomplish this such as heating the surface the one that is proving to be cost effective is spreading an ice control chemical onto the road as a preventive strategy the essence of anti-icing is to spread chemical a liquid solid or pre-wetted solid on the road before freezing precipitation starts or soon after it begins but always before a bond can form between the pavement and ice or snowpack this timely treatment enables traffic to disperse a small amount of snow or ice accumulation if plowing is necessary crews can clear the road more easily although these practices have been in limited use for many years anti-icing has come to mean a modern strategy that uses an array of new technologies such as the road weather information systems site specific weather and pavement temperature forecasting and sophisticated chemical spreaders as well as conventional technologies by combining new technologies with conventional practices anti-icing can provide two important benefits keeping roads passable and safe for a longer time and using smaller amounts of chemicals and abrasives to do so unlike anti-icing the strategy of de-icing allows a bond to form between the ice or snowpack and the pavement surface after snow has fallen and the ice or snowpack has bonded to the pavement maintenance crews spread the ice control chemical the de-icer must melt through the pack and still have sufficient concentration to break the bond this takes more chemical because its effectiveness is reduced as it gets diluted by the layer it melts de-icing is a much slower process taking hours or days depending on the air and pavement temperatures and the storm conditions also until the de-icing process can work crews must often spread abrasives on the snowpack to increase the road friction many agencies are seeking ways to reduce both chemical and abrasive use because of the application costs and the harmful environmental and health effects using anti-icing is a way to do this to determine the best techniques for a wide range of environmental traffic and climatic conditions the strategic highway research program evaluated anti-icing for two years in nine states California Colorado Maryland Minnesota Missouri Nevada New York Ohio and Washington the results from this study were so promising that it was continued for two more years and six more states Iowa Kansas Massachusetts New Hampshire Oregon and Wisconsin were added to the study here's what some of the study participants have to say for the anti-icing the savings is mostly in the efficiency that you get it where you need it you don't have to keep going back and putting it back where the big savings for us has been has been in the frost control instead of going out night after night and reapplying cinders and or salt we do it once a week or once every five days so we're saving in materials plus we're saving just in personnel hours and that's where our biggest saving has been plus in the accident factor the fact that we can get it out there when we need it and control the ice it really helps in cutting down there a number of our sections are showing 8 to 10 to 1 savings on de-icing over sanding or anti-icing over sanding particularly when we're morning in black ice typically take six passes at a yard per lane mile of sand and the sand cost is anywhere from ten ten dollars fifteen dollars a yard and one pass using anti-icing and we don't have to do anything more and this is a significant savings both in manpower and in sand what we have seen as is where we have put our major effort in training has paid off in many times first first use results the one of the examples is a crew in their first use put down three hundred dollars worth of material and they save over three thousand dollars in labor and materials and this was their first experience with it other than the training yeah I'd recommend almost everybody is because it will keep the snow from bonding it will make your cleanup faster and in a lot of cases like the city of Glenwood Springs asks us to shoot it because just for anti-icing it does two things it will keep the dust down from when we sand so they don't get dust in the storm in the storefronts and on the sidewalks and all over the cars and it'll keep the roads from icing up and freezing up on an average storm for two to three hours the crews that were initially charged with the applications were very skeptical to begin with and the more they used it the more impressed they were and currently they would use it everywhere if I had enough equipment to put it down a side light to this the superintendent in Bellingham is doing a test section that historically has 30 accidents a week due to snow and or ice during the winter months and he received a call from the state patrol the other day wanting to know what was going on because this winter they hadn't had any accidents on that road during the normal times when they would have and they were told that that was our test section and they thought whatever we're doing we're doing it right and they're always very happy with anything that we can do that reduces a number of accidents that they have to respond to the four years of study have shown that anti-icing is a valuable tool for winter highway maintenance especially for heavily traveled roads but it is not the answer to all snow and ice control situations there will be times when de-icing or other techniques may be needed anti-icing though has advantages that other techniques do not why use anti-icing it improves safety because pavements are kept in better condition during storms it generally requires less chemical and abrasive which is better for the environment and the infrastructure and it is cost effective because fewer treatments are required