On the average of multiple years, de-icing salt consumption used to grow at an annual rate of 2.5% from the 1960’s until a few years ago. Reasons for this underlying growth, which was observed in North America and Europe, was an increasing length of the road network, and an increasing level of winter service. The industry converted to the “just in time” supply chain model, which meant that traffic networks had to function without interruptions at any time and location in the country.
Also for recreational travel “back to black” – the complete removal of snow- was expected so that remote ski resorts in high altitude became easily accessible even under harsh winter conditions.
In the past decade, however, the underlying growth trend has reverted to declining de-icing salt use on the average of multiple years. Road networks in North America and Europe are not growing any more, as shown in the graph below.
In addition, winter service levels have in most regions not been further extended. Substantial efforts were made to use de-icing salt more efficiently for economic and environmental reasons. Best practices were developed, and important efforts were made to educate end users.
These efforts will continue and scientific and technological progress will further improve the efficiency of de-icing salt use:
- Weather forecast is expected to improve reliability and decrease the safety margin for salt use around 0°C and -12°C.
- Weather forecast will be faster and allow for more flexible use of de-icing equipment
- Computerized decision making will allow to make use of best practices independent of level of experience and education
- Improved spreaders to optimize mix of dry salt and brine as well as better control of spreading pattern
- GPS controlled spreading
- Real time information about residual salt levels
- Traffic guidance systems, and real time communication with traffic participants adds to traffic flow under winter conditions
All these factors are expected to further reduce consumption of de-icing salt over the next decades, beyond the climate change induced reductions.