The State of Maine has historically utilised sand with enough salt mixed in to prevent freezing for its winter snow and ice control strategy. In recent years, the State has come under increasing pressure to reduce its sand use, particularly in northern Maine due to the dust and costs related to sand pickup. With the advent of new technology for snow and ice control equipment, the time seemed appropriate to look at other approaches. However, any changes had to be environmentally sensitive and any increases in salt use would not be acceptable due to contamination of water bodies and private wells as well as corrosion of private and State equipment. The Department put together a team to look at and research the effects of moving to a salt only strategy in the State of Maine. This Team was charged with not only looking at the use of salt and other chemicals, but, the necessary equipment changes required to insure that the State didn't use any more salt than it ever did and to ensure that the travelling public would not be exposed to a poorer travelling condition, both during and after a storm. It was concluded that the Department could go to a salt only strategy which was coined "Salt Priority" without an increase in overall salt use, better travelling conditions both during a storm and after the event, and, potentially save millions of dollars through decreased sand use and pickup, decreased overtime and equipment use. However, it was also deemed necessary to move rapidly in modifying trucks with ground speed control, zero velocity spreader, ground temperature sensors and improved truck washing equipment. As part of the transition strategy, the Department joined with NCHRP to research the use of Salt Priority on local type highways and did some of its own research on the Interstate in southern Maine. This research was the first of its kind in Maine and showed the actual cost of sand versus salt and the road conditions experienced by the travelling public under both strategies. Resulting from all of this work was an implementation strategy that includes equipment purchases, training and annual evaluations. In addition, the Department instituted an outreach effort through the television media on the transition to Salt Priority that resulted in some interesting feedback, both pro and con. These efforts continue today with full implementation within 5 years. (Author/publisher)
Samenvatting