Measuring water levels: Geophysicist Pierre Corbin showing Laval Police spokesperson Nathalie Lorrain one of the pressure loggers installed in rain drains.
(Photo: Martin Alarie)
In case of flooding, emergency preparedness plan ready to go
Laval says it’s ready to face the spring thaw
Laval’s Citizens Protection Department says the city is ready for a wet spring, with officials citing the emergency plan implemented in 1999 and successfully tested in 2004 during an episode of memorable ice jams, as evidence.
This past Thursday afternoon, before the drop in temperature, residents of avenue Du Crochet, in Laval-des-Rapides (pictured on front page), had a little taste of what's ahead.
Unable to escape through blocked holes in manhole covers, the water accumulates to the great displeasure of pedestrians and motorists. Combined with rising water levels, this phenomenon could well intensify in the days to come.
"Three scenarios are possible: a gradual, moderate, or rapid thaw. If it's rapid, there's enough snow to bring about massive rises in water levels everywhere," admits Pierre Corbin, geophysicist at Hydro Méteo, the company mandated by the city to monitor water levels.
The vast amounts of accumulated snow, as the calendar moved toward warmer days and consequential risks, were part of discussions undertaken by the river oversight committee which met a couple of weeks for a pre-emptive preparedness session.
This umbrella group regularly brings together Laval experts in emergency preparedness, hydrometeorology, public works and public security, as well as representatives of various city services such as police and firefighters.
"For us, the preparation is the same. The intervention plan is there. We're waiting for the thaw," says Audrey Asselin, supervisor of civil security and emergency measures for Ville de Laval.
Defense arsenal
“The emergency plan is there, it just has to be applied,” says Laval Police Department spokesperson Nathalie Lorrain, adding that the vulnerable areas have been mapped, according to a colour-code determined by various levels of risk.
The Laval emergency-preparedness unit is always at the ready, collaborating with experts from Hydro Méteo. As well, the team also maintains constant contact with those responsible for the management of upstream dams. A dozen telemetric loggers and sounding rods have been installed throughout Ile Jesus to register water levels.
When water rises to dangerous levels, sandbags and underwater pumps are quickly put into use. “In 2004, we built buffers of snow near flowing water to absorb the overflow,” Mrs. Lorrain recalls.
Among the arsenal available for emergency management are Laval Fire Department boats. As the need arises, we have access to a privately-owned crane-equipped watercraft that can be used to break up ice masses, and the Hydro-Québec boat that can intervene in the waters surrounding the hydro-electric dam on the Rivière des Prairies.
And if, despite everything, the situation worsens and evacuation becomes a necessity, shelters have already been set up, with the city ready to provide beds and blankets. These precautions can be used in all emergency and crisis situations, Mrs. Lorrain specifies.
Public safety
On the periphery of the chain of intervention, in the event of flooding, experts from the Laval Department of Public Safety can be called upon to provide counseling, explains Serge Asselin, regional coordinator of public safety, health division, at Laval’s Health and Social ServicesAgency.
“Our role relates to (public) health. When health is in question, we can intervene.” Mr. Asselin cites mould that can develop in flooded basements as an example of how the agency can intervene, adding that insurance companies can also serve as a source of counseling for victims of this kind of damage.
Stop building
For the director of the Regional Environment Council of Laval (CRE) the emeregency plan is nothing short of delusion. The root of the problem of flooding is linked to “the lax attitude of the government and municipalities who keep on building (near rivers),” denounces Guy Garand. Our ancestors didn’t build in areas susceptible to flooding, because they didn’t have insurance and mortgages,” he explains.
Monitoring water levels: an on-going task
It's in Joliette, in the offices of Hydro Metéo, that front-line services for flood prevention in Laval are set up, on feeds from 15 telemetric stations dispersed throughout the island.
These stations are usually installed on the sides of the road, not far from flowing water and protected by a metal box not much bigger than a container of tools. In some cases, as on des Cageux Street, facing Ile Paton, they are integrated into a pumping station.
Their function is simple: measurement of river levels with the use of a pressure logger, placed in rain drains. "The sewer is connected to the river, based on the principle of water displacement," explains Pierre Corbin, geophysicist at Hydro Méteo.
The station is in fact linked to a second logger which measures barometric pressure in order to distinguish atmospheric pressure from that of the water accumulating in the sewers. Each measuring point is equipped with a modem, a lector and batteries which ensure 24-hour operation.
Other measuring instruments are also used for flood monitoring, such as staff gauges which complement the information decoded at their offices by experts at Hydro Méteo.
These gauges, embedded on river bank soil, are part of the tools at the disposal of the emergency response team, which makes regular fact-finding visits to the various sites.
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(Photo: Martin Alarie)
Steven Guilbeault - 
