The City plans for the maintenance and repair of roadways to optimize road pavement conditions across Barrie. The City’s pavement assets have a replacement cost of over $805 Million.
To look after this valuable asset portfolio the City employs a range of programs and strategies, from regular road patrols ensuring compliance with Provincial minimum maintenance standards to full reconstruction projects, and maintains a database of the City’s roads and their condition. On this page:
The Layers of a Road
Roads are constructed in multiple layers, each placed in several courses. The thickness and requirements of each layer and the total number of layers is dependent on factors such as weather, traffic volumes, and the native subgrade material on which the road is built. In general, Barrie's roads are constructed in 3 layers:
All layers act together and allow water to move from one layer to another until it reaches the subgrade where it's absorbed. Preservation activities completed on roads early in their life prevent water from seeping into the pavement structure through cracks and holes in the wearing surface. By taking care of the asphalt the City maintains the semi-impervious “cap” on the road.
How Roads Deteriorate
Many defects and road deterioration can be caused by excessive and continual water seepage into a pavement structure. When water is allowed to move through the asphalt and into the aggregate base, it weakens the structural integrity of the road and the normally harmless traffic will cause damage to the road over time.
The Freeze-Thaw Cycle
Because Canada experiences cold and warm seasons, Barrie's roads are exposed to freezing and thawing cycles. When water seeps through the cracks of the asphalt and freezes, the water expands and causes new cracks to form and the already existing cracks to become larger.
Pavement Renewal Strategies
In between a road’s initial construction and when it needs full replacement (reconstruction), there are several options that can reduce the total amount needed to be spent on roads to keep them in good condition and meet desired levels of service.
Preservation strategies, used earlier in the life of pavement when the road is still in good condition, are less expensive and faster to complete compared to strategies applied later in the life of the pavement, when the road has deteriorated more.
Pavement preservation activities are often equated to fixing the roof on your house. Replacing the shingles at regular intervals prevents water from getting into the house structure, which could cause expensive structural damage. Appropriately timed preventative investment in roads keeps water out of the pavement layers preventing cracks and defects from forming.
Windows of Opportunity
There is a window of opportunity in the life of a pavement where some treatments are suitable and others are not. For example:
- preservation activities performed on a road that has failed will have little to no impact and will be wasted effort.
- full reconstruction of a road that is young and in fair condition is unnecessary.
By completing treatments at the appropriate time within the recommended window of opportunity, the City can extend the life of a road, and reduce the total investment over the long term.
In an attempt to mitigate the effects of freeze-thaw cycles and other pavement deterioration, the City piloted (2018 to 2021) an Early-life Pavement Preservation Program in addition to continuing the Pavement Resurfacing Program. These programs aim to align the window of opportunity for each road with the appropriate pavement management treatment.
Cost of Renewal Strategies
The cost to reconstruct a road is 8 times that of pavement preservation. That means that by investing $1 in proactive pavement preservation, we can defer $8 worth of reconstruction.
Asbestos in Asphalt
Asbestos was used as an additive to asphalt from the 1960s to mid-1980s, added to asphalt mix to provide greater strength and performance. It is not used in asphalt anymore, but in many municipalities roads that were built between the 1960s and early 1980s could contain asbestos.
Asbestos is bound within the pavement, so there is very low risk to the public. Even when asphalt containing asbestos breaks down, it’s still bound within the asphalt. It does not pose a risk until it’s airborne, which happens when it’s cut into during the construction process.
Before road construction or maintenance begins, the City first tests the asphalt for asbestos. If the asphalt contains asbestos, special precautions are taken by workers removing the asphalt. These provincially legislated precautions include wetting the asphalt to prevent the dust from becoming airborne, and workers are required to wear proper protective equipment.