City of Ottawa issued the following announcement on Jan. 25.
Here’s the Fact: Salt isn’t very effective against ice in these bitterly cold temperatures.
Take a look at the chart below, you can see that at a temperature of 30 degrees, one pound of salt will melt 46 pounds of ice. As the temperature drops, salt’s effectiveness slows substantially below 30 degrees. In fact, when you get down to 15 degrees and below, salt hardly works at all.
Salt is much more effective at these very cold temperatures in sunshine. However, this can be dangerous when salt is applied to ice or snow and melts somewhat, because as the temperature drops below 15 degrees, that melted ice and snow (which essentially becomes a saltwater solution) can refreeze into a slippery dangerous layer of ice.
So what can we do when salt isn’t going to work well you ask? The City has partnered with the LaSalle County Highway Department to acquire a limited amount of 50/50 salt/sand mix material to help with traction on hills, major intersections, and some of the major East/West roads during this anticipated stretch of bitterly cold temperatures. This is a short-term solution that enhances traction, but does little to remove ice without that sunshine and rising temperatures. The City Public Works crews will still be salting, but the most traveled roads and hills are the priority during this very cold weather.
And remember, always drive more defensively during these bitter cold temperatures. This means slowing down on icy stretches, and giving more time to stop. Pay extra attention to the pavement you are walking or driving on, so ice doesn’t sneak up on you and cause you big trouble.
Original source can be found here.
Source: City of Ottawa