Icing Accidents Eliminated in the First Year of System Operation
Accidents on an Ontario bridge prone to black ice
formation were completely eliminated during the 2000-2001 winter. This
dramatic improvement, from 14 icerelated
accidents the previous winter, can be attributed to the
installation of the first automated anti-icing bridge spray system in
Canada. The system, Fixed Anti-icing
Spray Technology (FAST) has the potential for
widespread use at problem locations.
The bridge, a ramp at the Highway 401-416 interchange
near Prescott, developed icing problems the first winter it was opened.
Moisture from the nearby St. Lawrence
River condensing on the deck, bridge geometry, and the
numerous freeze/thaw cycles that occur in the area, combined to create
frequent icing conditions that crews
couldn’t accurately forecast. The Ministry of
Transportation of Ontario, anxious to find a solution, approached Mark F.
Pinet & Associates Limited of Ottawa.
Mark Pinet, President, Mark F. Pinet & Associates,
noted “the solution we came up with was to link a Road Weather Installation
System (RWIS), which monitored moisture, air temperature, humidity,
precipitation and pavement conditions, to a system that can spray
anti-icing chemicals on the deck surface.” When the RWIS determines that
icing conditions have developed, a signal to spray is automatically
generated, and if desired there
is no need for human intervention. “If we can have a
system where the black ice doesn’t develop, that would be the goal across
the province and we would have far
safer highways during the winter time,” said The
Honourable, Brad Clark, Ontario’s Minister of Transportation.
Another benefit to the system is that smaller amounts
of chemicals can be used due to the constant monitoring of deck conditions.
The reduced impact on the concrete and steel in the bridge is expected to
both lessen rehabilitation costs and extend structure life.
FAST could also reduce legal liability, if a May 2001
decision of the Ontario Court of Appeals is any indication. In that case,
the province was found liable for a 1988 accident in which a driver lost
control while crossing a bridge on Highway 401 and suffered severe
brain damage. Damages of $4 million were awarded after
finding that road crews had not responded to weather reports calling for
For more information on the FAST system,
Mark F. Pinet & Associates Limited at (613)
825-5716 or by email