Friday, December 5, 2014

Understanding The City’s road maintenance snow and ice standards

Today marks the final day of The City’s Seven Day Snow Event Plan. This means City Roads crews will consider their work in cleaning up after our most recent blast of winter finished by tomorrow (Saturday) morning.

So, what does “finished” mean? Depending on who you ask, you are likely to get a different answer. But from a City standpoint, there are well-defined standards for snow control on our roads that keep our streets safe while staying on budget.

The City sands, salts, and plows roads and sidewalks based on a Council-approved priority system, with the busiest roads deemed the top priority.

What does a complete road look like?
Under the Snow and Ice Control policy, the busiest roads (Priority 1s or P1s) are plowed first and snow is cleared down to the pavement. Roads with lesser volumes of traffic, for instance in our residential areas, are typically done last and are simply “bladed” in order to pack down the snow to a drivable or passable condition.

Priority 1 and 2 routes - Bare Pavement Standard
In 2011, The City implemented a Bare Pavement Policy as the standard for snow clearing on Priority 1 and 2 routes (P1 and P2).

On P1 and P2 routes, crews will plow the snow so the pavement is showing on through-lanes. Crews clear these roads to bare pavement by first putting down material to prevent iciness and soften the snow on the road. Crews will then use a front plow, a plow on the front of a sander that pushes the snow to the side of the road, or a belly plow, a plow underneath the truck that moves snow to the side of the road.

Residential roads – Packed snow standard
In 2011, Council voted to include residential streets in The City’s snow control efforts. Under the policy, residential roads (P3 & P4 routes) are addressed but are not cleared to the pavement like Priority 1 and 2 routes.

Crews typically “flat blade” the roads in residential areas which means a sander operator tilts the blade down and scrapes the snow, packing it down in attempt to minimize ruts and make the road passable. Crews will use their plows to knock down snow ruts to 12 cm on residential roads and will apply material like salt or pickle, a salt/gravel mixture, depending on road temperatures.

Roads are flat-bladed in residential areas in an attempt to make roads passable so that all emergency vehicles are able to maintain access while also keeping windrows (the snow pushed to the sides of the road) as small as possible.

For more information on The City’s Snow and Ice Control Policy visit
Roads’ priority system
Priority 1 (P1) routes include major commuter roads that carry 20,000 vehicles or more per day as well as roads downtown that carry 8,000 vehicles or more per day. Examples include Macleod Trail, Glenmore Trail and Crowchild Trail.

Priority 2 (P2) routes are the feeder roads that run in and out of communities and typically carry 5,000 to 19,999 vehicles per day. Many of these are Transit bus routes.

Residential roads with school and playground zones, hills and intersections with stop/yields are considered a Priority 3 (P3), while the remaining residential roads that have the lowest traffic volumes are considered to be a Priority 4 (P4).

Does the City of Calgary do Snow Removal?

Snow removal involves plowing snow to the side of a road, and then using a snow blower to collect the snow and load it into the back of a dump truck. The snow is then taken to one of The City’s snow storage sites.

Snow removal is typically only done in the downtown core, and along major roadways where there is no extra space to pile snow.


  1. why can't we just put salt on the roads; this will keep not only our roads clean but cars will be clean and with no crack windshields.
    It will also keep the shoulders clean and saves The City huge sum of money by not doing summer shoulders clean.

    1. Factors such as the intended purpose of the material and the climate's effect on the material are taken into consideration when determining how to best treat the roads. An anti-icing agent is used when road temperatures are around 0° Celsius as a preventative solution. Salt is most effective when road temperatures are between 0 to -10°C; pickle (a sand and salt coated gravel mixture) when below -10°C; and sand chips when below -20°C.

  2. Snow is not the only condition the city should be concerned about. The city should be supporting pedestrians and cyclists by maintaining sidewalks and pathways during icy periods as well. The thin layers of ice on the roads, sidewalks and pathways are much more hazardous than packed snow. I find it much easier to be out and about as a pedestrian when there is snow but at times like the present, it is difficult to find routes that are not treacherous. I would think that the city would like to encourage its residents to not rely on vehicles, both for environmental and health reasons. Simply keeping sidewalks and pathways clear of snow AND ice would go a long way to improving air quality conditions and promoting an active lifestyle for Calgary residents.

  3. Personally I never seen the benefit of the sanding (actually it is not the sand, it is rock chips) other than for car and windshields manufacturers. When the road is covered by the fresh snow rocks are not working; when its icing, all rocks are already on the road side; when its dry - it is just damage your vehicle. There is no any better protection other than winter tires. Period. City just spending lots of money to spread those rocks, then to collect it. Quite often those rock just spreading on the absolutely dry road.
    In my opinion, by such type of "sanding", instead of roads cleaning, City just wasting money and our cars.

  4. At what point does the city roads dept. lay down a coat of their "special" mix on residential streets? Brookgreen a skating rick with patches of pavement showing. A roads dept. pick-up appeared on Friday p.m , Driver spent time on the cell, but that`s it.. Likely on
    another atter. With this mild weather, one would think roads dept. would be spreading their "cheer" aka. icemelt, before it gets "too cold"..

  5. Driving today was hell; Calgary is just not doing enough to keep drivers safe and should look to the Toronto area to see how it should be done: more salt, especially at major intersections; the Deerfoot is barely navigable and that is not acceptable for a city this size. I lived in Toronto and worked in Mississauga for five years, which I would not do in this city considering the winter road conditions! We may get the Chinooks in Calgary but in Toronto, we get the (Great) Lake effect, which is comparable in that it makes the climate milder and warmer at times; but if the City road maintenance managers thinks it does not warrant real winter road maintenance, they are in denial!!