How many city crews does it take to fill potholes? As many as we can deploy! The freeze/thaw cycles have now taken hold, and it’s wreaking havoc on our roads, sidewalks and winter cycling network. The Roads and Parking Services team has sprung into action to address the increased number of potholes throughout the city. Last week, work began on filling potholes, and this week, we will begin redirecting additional resources and deploying more crews to fill potholes. We’ve even brought in reinforcements, and two Pythons have arrived in Ottawa!
Python pothole patcher
We have currently secured 2 Python 5000 machines, or as we like to call them – Python Pothole Patchers. They arrived last nightat 7pm and will be working in different areas throughout the city. They will work 12-hour shifts (day and night) over the next few weeks as we continue to experience freeze/thaw cycles. So, what are they? The Python Pothole Patcher can fill a pothole in less than two minutes. With the operator working safely from inside the cab, workers are protected from oncoming traffic as the work can all be completed without the need of stepping foot outside of the vehicle.
The Python Pothole Patcher is coming to a neighbourhood near you! If you spot our machines working in your community, please wave to our operators from a safe distance. If you see them while travelling, please, do not pass them. They may be filling a pothole but remember, it will only take a few minutes!
How are potholes formed?
Potholes are formed when water (from rain or melted snow and ice) seeps into small cracks or holes in the road. As temperatures drop, the water under the road freezes and expands pushing up on the road above, creating larger cracks – when the temperature rises above zero, the water evaporates and leaves an open space under the road. The weight of cars and trucks travelling over these weak spots breaks the asphalt, resulting in potholes.
How do we repair potholes?
Potholes are filled by cleaning the hole of debris and water, then packing it with asphalt and rolling or pounding it down. At this time of year, some potholes in high traffic areas may need to be refilled more than once. This happens because water works its way back into the hole preventing the asphalt from forming an adhesive bond with the pavement.
Filling potholes in winter
In winter, conditions are not ideal for pothole repairs. The unstable conditions, including ice and water in the holes, as well as the cold temperatures and frequent freeze / thaw cycles, prevents the patch from adhering as well to the roadway making the repair temporary. Products that staff use to repair potholes during the winter months are Cold Patch and Warm Mix asphalt.
Cold Patch asphalt is a blended asphalt material which can be stored for extended periods of time. It can be used in all temperatures, does not require special equipment to compact and can be applied directly to the roadway without heating.
Warm Mix asphalt can be used year-round and produced at a lower temperature using different adhesives in the mix. Once the material is heated, the adhesives become thinner allowing improved workability and flow. The material can be manually compacted with a tamper, or shaped and compacted with power plate tampers or rollers.
Next steps
Based on the forecast, we are anticipating several freeze-thaw cycles over the coming weeks. The city has already experienced 37 freeze/thaw cycles this winter season. Residents can expect to see our pothole crews across the City. Ottawa winters are hard on our infrastructure, and this year in particular, we are anticipating an increased number of potholes. We appreciate your patience as we transition between different winter maintenance activities and prioritize and deploy resources to complete our operations.
