Increased moisture and heavier traffic in recent years may have hastened the deterioration of Prince Albert’s roads, according to a civil engineering professor at the University of Saskatchewan.
© Herald photo by Matt Gardner
Barriers and signs seal off a stretch of 10th Street East set for re-paving as part of the city’s $4 million city asphalt repaving program, which has nearly reached the halfway point. A University of Saskatchewan civil engineering professor says increased moisture and traffic may have played a role in accelerating the deterioration of Prince Albert roads.
Drawing upon his experience as managing partner for research and development at asset management consulting service VEMAX, Dr. Gordon Sparks pointed to the toll that greater traffic, precipitation and humidity can have on city road systems.
“The last number of years, the amount of moisture has been high … and basically the strength of the subgrade decreases as the moisture content increases,” Sparks said.
“My guess is that that’s probably accelerated the rate of deterioration, and when you’re getting near the end of the useful life of a pavement, and then you happen to wind up with wet years -- then boy, it could really fall off the end there really quickly.”
Sparks also said that the freeze-thaw effects on roads can be more dramatic when the soil contains higher levels of moisture.
He pointed to other regions of Saskatchewan that have seen heavy rain and runoff over the last three to five years and subsequently found their roads deteriorating much more rapidly, as the high moisture content of the subgrades sapped their strength.
Another potential factor, Sparks suggested, was greater traffic on roads as the result of Saskatchewan’s booming economy, which has also contributed to population growth.
“You’ve got probably quite a lot more traffic now than you had five or 10 years ago, and particularly on main routes with truck traffic and that sort of thing,” the professor said. “That can certainly accelerate the deterioration as well.”
To combat such wear and tear on local roads, the City of Prince Albert has enacted a $4 million asphalt repaving project for 2013 -- double the amount spent last year -- with the worst roads being given top priority.
Manager of capital projects Wes Hicks said on Friday that the city was nearing the halfway point on its paving project, roughly in line with expectations.
In determining which roads require the most attention, the city uses a computer program based on a consultant’s inspection report, garnered through non-destructive testing methods such as visual inspections, lasers and sewer cameras.
“It all ends up as a PQI, which is the Pavement Quality Index for each segment of roads,” Hicks said.
“Basically that PQI is a rating from zero to 100, like a percentage, and that gives us the Pavement Quality Index for each segment of each road in the city of Prince Albert.
The last number of years, the amount of moisture has been high … and basically the strength of the subgrade decreases as the moisture content increases. Gordon Sparks
“Then the program spits out the worst roads and tallies them, and we try to take the worst roads in the city and work on those ones first.”
Though the city has prioritized the worst roads, it must also account for the timing of events within P.A. to minimize disruptions.
For example, paving is currently underway near W.J. Berezowsky School, Fourth Street East, Seventh Street East and 15th Avenue East.
“We’re doing that right now because it’s summertime, so you’re not infringing on any issues with the school,” Hicks explained.
“Likewise, we did the west side of town over on MacArthur (Drive) and that started right at the end of the school year, so that whole area there was done.”
Paving in the downtown area is expected to commence after events such as the Prince Albert Exhibition Summer Fair and its accompanying parade have taken place.
The advanced age of downtown infrastructure will also require extra preparation time.
“We have to be there after we get all the sewer photography, because downtown is very old and the sewer photography has been ongoing,” Hicks said.
“For the last couple weeks here, you’ve probably heard or seen those machines downtown, and so that kind of work is taking place right now. Then we can start with the paving in August downtown.”
For Sparks, taking a more proactive approach to infrastructure maintenance is key to preventing problems further down the line.
He is a firm proponent of managing assets on a “life-cycle basis,” in which planners consider costs for the full life of the asset.
By fixing seemingly small problems early on, Sparks indicated that governments could avoid much more serious structural issues later that would necessitate prohibitively expensive repair efforts.
“Don’t wait for three or four years to fill the cracks, because if you do, what could cost a few bucks to fix all of a sudden costs $10 or $20 to fix.”