Morier Dam | New inspection reports emerge

(Chute-Saint-Philippe) Inspection reports that had not been made public until now reveal that Quebec was aware for months of the phenomenon of water accumulation at the foot of the Morier dam, which was invoked to justify the evacuation in the middle of the night of 1,900 residents of the Hautes-Laurentides last winter. Badly affected, a small municipality that would be partially submerged if the dam broke is now suing the State for “negligence.”

Calm has returned to the streets of Chute-Saint-Philippe on this hot July afternoon. A few boaters are sailing on Petit Lac Kiamika, others are driving to their cottages.

But beneath the surface, tensions are high.

A lawsuit filed in Superior Court by the municipality, its mayor, Normand St-Amour, and its general manager, Éric Paiement, sheds new light on the standoff that has been going on since the fateful evening of December 3.

In the middle of a snowstorm, some 1,000 homes, a third of which were in Chute-Saint-Philippe, were evacuated urgently after inspectors from the Ministry of the Environment noticed an accumulation of water at the foot of the Morier dike.

Owned by Quebec, this immense pile of earth and rock located in the middle of the forest, upstream from Chute-Saint-Philippe, holds back the waters of the Kiamika reservoir, which contains the equivalent of 100,000 Olympic swimming pools.

The municipality accuses Quebec of having failed in its duties to guarantee the safety of the structure which, if it were to give way, would flood part of the village in less than two hours.

The instability of the Morier dam “is not due to a natural hazard that no one could have foreseen, but rather to manifest negligence with regard to its maintenance,” they claim in their lawsuit, which was joined by around fifty entrepreneurs in the region who were forced to close their businesses for 11 days, during the evacuation.

“Regular inspections, carried out rigorously by a prudent and diligent engineer” would have made it possible to note the degraded state of the dam, allege the authorities of Chute-Saint-Philippe, who claim to have noticed worrying signs themselves and to have warned Quebec of them in 2019.

Documents retained

Chute-Saint-Philippe’s appeal also lifts the veil on several technical documents obtained by the municipality’s lawyers through a request under the Act respecting access to documents held by public bodies and the protection of personal information.

Documents that were the subject of similar access to information requests previously made to the Environment Ministry in the wake of the December evacuation, but which are not posted on the organization’s website as is standard practice, the ministry found. The Press.

These include reports of reconnaissance visits carried out at the Morier dam.

This dam, classified as “high capacity”, must be inspected every month under the Dam Safety Act.

The most recent of these reports, dated November 21, does indeed mention “a significant increase” in water at the foot of the dike. It coincides with the dates when the Ministry of the Environment claimed to have observed an accumulation at the foot of the structure, a “first sign” that the structure is in poor condition.

But this accumulation of water is also reported months before the evacuation. “Permanent pool of water, increasingly large,” noted the Ministry’s inspectors already in July 2023.

According to François Brissette, a professor in the construction engineering department at the École de technologie supérieure, who consulted the reports at the request of The Press, “the decision to evacuate was necessary.”

“At that point, the evacuation was the right thing to do. But how come we didn’t see the problem before evacuating? It was a problem that was progressing, it was getting bigger and bigger, and so they made the decision,” he explains.

Missing information

Crucial information is still missing, says the hydrology expert, namely measurements taken in piezometers, long tubes inserted into the Morier dam that allow the water level it contains to be measured. And to observe, if necessary, whether it becomes problematic.

“If I am in charge of the inspection, it is clear that I want to see the piezometers,” explains the professor.

However, nowhere in the documents provided by the Ministry is there any mention of recent measurements taken in the piezometers of the Morier dam. “I am not into conspiracy theories, but I find it surprising that in this court case, the measurements from the piezometers have still not been released,” says François Brissette.

Despite a long list of questions sent to the Ministry of the Environment, the latter indicated that it would not make any comment “since this matter is before the courts.”

But this is all the more worrying because the failure of the Morier dam would be catastrophic, estimates François Brissette. “If a dam like that gives way, you’re going to have the equivalent of the St. Lawrence River flowing into the river for quite a while.”

“Superficial” interventions

The authorities of Chute-Saint-Philippe deplore having had no news from the government regarding the work carried out on the dike, despite the sword of Damocles hanging over the village.

Last April, Quebec assured, through a press release, that the structure was now “safe” thanks to work “carried out successfully”, in particular the construction of a drainage trench at the foot of the dike.

However, these works are “superficial interventions,” says the municipality of Chute-Saint-Philippe. The fact that water is penetrating the enormous pile of earth, “a problem that initially seemed to be the source of the instability of the dike,” would therefore remain, it says.

“Preliminary expert reports show us that the issues are still very real,” said the lawyer responsible for the appeal, Mr.^e Frederic Bedard.

“It is clear that [l’enjeu d’infiltration d’eau] is not resolved. The rockfill downstream is a big plaster, it is not a solution for the next 30 years,” adds Professor François Brissette.

Without fanfare, the Ministry of the Environment awarded a contract last May to the company Géowave Inc. of Granby for “geophysical surveys” of the dike with a view to a “drilling campaign” at the end of July.

A series of examinations which suggest more important work to come, believes François Brissette.