The road repair budget is preparing for a hit.
The weather this week might be nice for those wishing for a winter reprieve, but it is murder on asphalt. The effect of cold temperatures on water, especially suddenly, is one of the leading culprits in the making of the basic pothole.
"I've been on councils and had budget deliberations for so long now, I don't see weather the same way everybody else does," said Mayor Dan Rogers. "Some see these warm spells as a break in the monotony of winter, but I see a potential impact on our budget."
The science of it, in brief, is that when a warm snap hits the city, the water held in frozen stasis releases into its liquid form. This percolates through the road surfaces and gets into the road beds.
This does little or no damage, but water, when frozen, expands in size, so when it freezes again, all the percolated water that hasn't drained away yet suddenly pushes hard against the road surface from below. The pavement is often no match for the freezing water and the asphalt breaks apart.
This doesn't always cause the pothole immediately, but when spring comes and the frost fully lets go, that is often when parts of the road go to bits and pieces.
The more often this freeze-thaw-freeze action happens in a year, the worse your roads are going to be.
"Climate change is a factor winter cities are grappling with, and Prince George is probably the municipality who has to face it most in British Columbia," said Mayor Dan Rogers. "When it freezes and stays cold all winter, that's fine, but freeze-thaw cycles do a lot of damage to the pavement."
The City of Prince George has more than 1,200 kilometres of paved roads and streets. City Council has approved, in recent years, incrementally bigger amounts of money to fix the roads. Rogers said he hopes to see another increase in that department's budget by about 10 per cent, with council approval.
In 2010, council committed about $3.4 million to 13 road rehabilitation projects, which was a $215,000 increase over 2009. Thirteen projects were identified as priorities, but due to money left over at the end of these projects, other problem areas got new pavement too.