Skip Navigation

Pothole Advisory

The City of Thunder Bay’s Infrastructure & Operations Department takes a number of steps to ensure quick efficient repair of potholes. With the significant snowfall of this winter there are many roads in the City affected by potholes. Periods of warmer temperatures create a freeze thaw cycle. Warmer days and cold nights damage our roads and create potholes.

To report a pothole call 625-2195, 24 hours - or Report a Pothole online.

Frequently Asked Questions

Q) What causes potholes?
A) Potholes are created when moisture seeps into the pavement and sub-base, freezing, expanding and then thawing. This weakens the pavement. Traffic loosens the pavement even more and it eventually crumbles and pops out.

Q) Why do so many potholes occur in the spring?
A) Spring temperatures warm the cold pavement during the day, melting and evaporating any frozen water. These warm temperatures also melt the snow and the resulting water flows into the pavement and freezes at night when temperatures drop. This freeze thaw cycle causes a great deal of damage to the roads, creating voids under the pavement that can eventually cause the pavement to break up. Much of the damage goes unseen under snow banks along the sides of our roads. As the sun melts back the banks it exposes these potholes to traffic. Roads with high traffic volumes tend to have more potholes due to the sheer weight and volume of traffic.

Q) How long will it take to get if fixed?
A) It will depend on where the pothole is located. Potholes on a main street will be fixed before potholes on residential streets where traffic volumes are less. Maintenance crews are constantly on the lookout for potholes, but the City welcomes citizen calls as well.

Q) How are potholes repaired?
A) During cold weather repairs are made using a ‘modified’ cold patch asphalt. Modified cold patch has the ability to wick water out of a pothole. This wicking characteristic speeds up the repair process and makes it more permanent. During the summer, hot asphalt and compaction rollers are used to seal up shallow potholes and cracks in road pavement. This type of preventative maintenance helps to stop potholes from forming in the spring.

Q) Can anything be done to prevent potholes?
A) Roads today are being built to reduce their moisture capacity and researchers are working to develop a better, more durable pavement.