Undoubtedly much of our winter management tactics are based on noticeable weather indicators: air temperature, sunlight, cloud cover, shadows from buildings, precipitation. How about the surface temperature where you are going to spread ice melt?
Pavement temperature and air temperature are yards apart in usefulness. Air temperature is what you see when you check the day’s weather. Weather stations report air temperature, which is measured at least 6 ft. in the air. The air temperature is not helpful when determining which ice melt to apply to surfaces on the ground.
The surface temperature can be measured with a no-contact, infrared temperature sensor. These devices can be hand-held or mounted to the side-view mirror on a truck. Hand-held sensors can be purchased for about $50. Always calibrate a hand-held sensor by leaving it outside for 10 minutes before using. Never use a hand-held sensor while driving. Mirror-mounted sensors are just as useful and around ten times more expensive.
Note: these can be purchased on Amazon and in some hardware stores
Pavement temperature will vary within an area depending on sunlight, shading, pavement materials, and other factors. Pavement temperature as well as type and accumulation rate of precipitation will determine if and what mechanical methods to be used and which ice melt should be applied
The following chart gives a range for application rate based on pavement temperature. Factor into the chosen temp range if the pavement will be warming or cooling (warming = less ice melt, cooling = more ice melt)
* Dry rock salt is not recommended in cold temps. It is slow to melt and leads to over application.
** Winter sand contains ≤ 5% salt. It will not melt snow or ice. It is used for traction only.
To use an interactive version of this chart, go to the Salt Wise application calculator.
Documenting the conditions and strategies for every storm can help you improve performance and save materials. (an example documentation form is available at Wisconsin Salt Wise training resources). It can also help you reflect on ways to reduce cost, infrastructure corrosion, landscape, and environmental damage. If ice melt is found on dry pavement after a storm, too much was applied and should be swept up.
Like in sports, a meeting following a big game is designed to go over what went well and what needs work. Post-storm meetings are to share constructive ways to improve, better understand what happened, and make adjustments before the next event. If it is impossible to meet in person, post the results, and share them with the team. This will help you decide and remember which strategies work and which don’t work for each area you are treating and for different storms.