The City of Chestermere is exploring new options to control dust on Rainbow Road.
Rainbow Road has become a popular route for drivers, with the north counters averaging more than 27,000 vehicles each month in the summer, and the south counters averaging more than 20,000 vehicles each month.
City Director Cam Wong presented viable dust control options for councillors to consider during the Sept. 13 council meeting.
Between June to August, the city applied 153 hours of grading and watering to Rainbow Road.
“Grading is done to level out the surface, remove any ruts, and smooth out the area where the road transitions from asphalt to gravel to help reduce the noise,” Wong said. “Watering is done to help control the dust and activate the dust control agents.”
For dust control, the city has been using calcium chloride, which is considered the best practice, and the most cost-effective method, Wong explained.
Calcium chloride is a clear liquid that naturally attracts and retains moisture, and when applied the road will look damp.
“It has an easy application process where it’s sprayed from a truck and can be driven on a couple of hours later,” Wong said.
Used oil can also be used as a dust suppressant that creates a crust on top of the road surface.
“Putting down oil is usually messier, and it can wreak havoc on cars if it’s not dried long enough,” Wong said. “Generally, what happens is, it starts to break apart when it deteriorates and large chunks can come out, making large potholes.”
Applying the used oil to the roadway is between two and three times more expensive than applying calcium chloride.
“Compared to used oil and other dust controls, calcium chloride lasts and outperforms the other ones. It’s the most environmentally friendly dust control available on the market, receiving the lowest toxicity reports compared to other products,” Wong said.
The city has also researched other options such as asphalt binders and adding a clear coat sealant.
The asphalt binder and sealant option would require the city to provide a flat base surface, with an estimated cost of around $250,000, and base work of around $30,000.
The city has also reached out to vendors who are ending projects to complete a trial strip along Rainbow Road.
“They are ending their projects now, depending on when they end their season, and what they have left for material, they might be able to do trials, but they can’t commit at this time,” Wong said.
The final option is to pave the road.
“It’s apparent that we have a fair bit of traffic on that road, which is good, it shows residents like that road. It’s important that we look at improving that road because we have confirmation that residents are using that road,” Mayor Jeff Colvin said. “Appropriate dollars need to be put in that direction.”