DCC Set To Prepare City Roads For Winter - Grit and CMA Application Use Imminent

Monday 28 May 2012, 4:02PM
By Dunedin City Council


The onset of winter means the DCC’s winter road maintenance programme is about to recommence.

The city’s major roads will be inspected by roading contractors during the hours of darkness and their condition assessed. Those reports will be posted on the DCC website, at, and updated regularly from 6am. Motorists are urged to consult this site before driving on the city’s roads on mornings when frost, ice or snow are apparent or forecast.

Anti-icing agent Calcium Magnesium Acetate (CMA) will be applied on main arterial roads to prevent ice forming, and grit trucks used where appropriate. A map showing roads where these are applied is also available on the above webpage.

CMA costs the DCC approximately $3000 per tonne, which makes enough solution to cover the 30 lane kilometres that have been prioritised (each stretch of road is two lanes). There is an additional cost of $500 for the contractor to mix and spray this quantity of product on the road., CMA has been proven to have no harmful effects on the environment and generally washes away in the rain.

The grit cost of $1000 for a truckload (eight tonnes) is for material which is sourced locally and includes the cost of both the distribution and collection of the grit. The contractor has a 96-hour period in which to remove the grit, except for that at key intersections which must be removed by 5pm of the day following application.

Other options for clearing ice include salt, which is also effective on snow. It, however, has possible detrimental effects on the adjacent land and natural water ways and can, therefore, be used only in areas where it would wash directly to stormwater systems that flush out to sea. Salt would be ideal for difficult carparks and private driveways.

In bad weather, all road users are urged to seriously consider whether their journey is necessary and to have regard to the road and weather conditions when deciding how and where to travel.