22/06/2026
Something to be aware of.
https://www.facebook.com/share/p/1G6QZyvQLh/
If anyone knows ice, itās Americans ā so weāve gotten their help to refine how we anti-ice roads in Central Otago.
We already apply anti-ice chemicals to our state highways in winter. We mostly use CMA (calcium magnesium acetate), which is non-corrosive and biodegradable.
CMA works by preventing frozen water from bonding together on the road, so the likelihood of ice forming is massively reduced.
We usually apply CMA in one dose ahead of ice forming. Now, using a new formula weāve developed along with the experts who came up with CMA, weāll be applying an initial coat of CMA well ahead of ice forming, and following up with subsequent thicker coats.
This has a major benefit to you: The new method also preconditions the road for future coats, making the CMA much more effective and reducing the likelihood of ice forming. It also makes the CMA less slippery right when itās initially applied, which makes your travel smoother on recently-treated roads.
You still need to be careful if youāre travelling on a road where weāve just applied CMA, especially if come across roadworkers applying the CMA. Pass slowly and keep as safe a distance as possible. The road immediately behind the roadworkers may still be a bit slippery.
As you can see from this photo, when CMA is applied it makes the road look wet.
Weāre constantly monitoring how winter weather is affecting travel on the state highways, but conditions can change quickly in winter and the speed at which snow and ice can appear means thereāll be times we havenāt yet been able to spread grit or the anti-ice treatments.
Intense periods of weather such as snow, ice, and severe rain can make it unsafe to travel which means we may have to temporarily close state highways. Always check our page to see if state highways are affected before you travel.
