https://www.kenoraonline.com/local/city-defends-salt-strategy

City crews are out in the community clearing away snow after the winter storm.

Kenora's icy roads were front and centre yesterday, as operations manager Jeff Hawley led this month's committee of the whole by addressing questions about the city's use of salt.

After confirming the city does, in fact, buy about 500 metric tons of salt and sand a year for winter road maintenance, Hawley repeated his comments from yesterday, saying the mix of salt and sand is only useful within a certain temperature range. Below -18, the salt is as effective in melting ice and snow, but the mix still adds traction, he noted.

By comparison, MTO uses pre-treated or pre-wetted rock salt on its highways, in an effort to pre-treat pavement. This makes snow and ice removal easier.

In their Winter 2018 edition of Road Talk, the ministry says they'll use between 90 kg and 130 kg of pre-treated rock salt for every kilometer of two-lane highway. This compares with 130 kg to 170 kg of dry rock salt for every kilometer of two-lane highway.

Some communities will also use a salt-water or brine solution on their highways. However, Transportation Association of Canada discourages the use of salt (sodium choloride -- NaCL), due to the impact on:

• air quality
• surface and ground water
• vegetation
• soil
• wildlife
• vehicle and structural corrosion

A straight salt application costs about $100 a ton. The cost of brine can be as about eight cents a gallon, but adding the clean-up costs can quickly inflate the cost to $1,900/ton, according to landscapers and property managers with the American Snow and Ice Management Association.

According to MTO, their goal is to meet the bare pavement standard after winter storms 90 per cent of the time. Their standard varies depending on winter traffic volume and road type. Some highways with low traffic remain snow packed for most of the winter.

Otherwise, standard timeframes following the end of a storm are:

• Eight hours for freeways and multi-lane highways, e.g. Highway 401, Queen Elizabeth Way, Highway 11 four-lane sections (Class 1).
• Sixteen hours for high traffic volume, two-lane highways, e.g. Highway 17, Trans-Canada (Class 2).
• Twenty-four hours for medium traffic volume, two-lane highways, e.g. Highway 35 (Class 3).
• Twenty-four hours to centre bare for low volume, two-lane highways, e.g. Highway 516 (Class 4).

City of Kenora roads are cleared based on three priority levels:

• Priority 1 – these roads are cleared first and will be cleared within 36 hours of a snowfall event
• Priority 2 – these roads will be cleared AFTER priority 1 roads but these roads will also be cleared within 36 hours of a snowfall event
• Priority 3 – these roads will be cleared AFTER priority 1 and 2 roads are cleared and within 72 hours of a snowfall event