Laval will invest 60 million in a mega-drinking water reservoir

2023-10-16 03:42:37

The Boyer administration plans to build a huge drinking water reservoir, the capacity of which would be equivalent to more than ten Olympic swimming pools in the Chomedey sector.

The idea is to “make Laval more resilient”, explains in an interview with Courier Laval Mayor Stéphane Boyer discussing the impacts of climate change.

Ultimately, Laval plans to have three reservoirs of this nature, which would respectively be supplied by the drinking water treatment plants of Chomedey, Pont-Viau and Sainte-Rose.

Earlier this month, the municipal council awarded a contract worth some $640,000 to the engineering firm Stantec Experts-conseils. Its mandate: to carry out preparatory studies and the preliminary design of a 40,000 cubic meter drinking water reservoir in Chomedey, including an opportunity study for the choice of the site for the reservoir.

This first basin to be buried underground would make it possible to store no less than 40 million liters of water, which would provide “room for maneuver” in the event of a breakdown at the Chomedey production plant or even a period of severe low water. by an unusual drought, which would limit its water supply from the Rivière des Prairies. Of the three planned reservoirs, that of Chomedey is by far the largest, given that it will serve the most densely populated sector, including the city center.

“When the reservoirs required in the Aqueduct Master Plan are completed, there will be an autonomy of 12 hours considering that one of the three drinking water production stations is shut down”, specifies the Head of Business by email public, Philippe Déry. He adds that “the capacity of the reservoirs must be put into perspective with the needs of citizens, institutions and businesses, the continued development of Laval as well as the growth of its population.” Access to these reservoirs will also avoid overtaxing other factories to compensate for a drop in production that could affect one of them.

This professional services mandate will cost nearly double what the Water Management Department estimated at $344,925 before launching the public call for tenders. At $642,710, taxes included, the offer submitted by Stantec Experts-conseils was recommended by the Supply and Purchasing Department, then accepted by elected officials. Of the two competing bidders, only the Stantec firm obtained the minimum quality pass mark set at 70%.

“A more detailed estimate would possibly have reduced the observed gap,” we can read in the decision-making summary sent to the executive committee, of which the Courier Laval got a copy. This unfavorable difference of $300,000 is also attributed to the fact that “the consulting engineering market is not very present for this type of mandate at the moment” due to the numerous projects and construction sites in progress and a lack of resources.

At the end of the 43 days of publication, five suppliers had assumed the costs for the tender documents, three of which ultimately did not submit a bid.

Finally, if the Stantec Experts-conseils report is expected at the end of the first quarter of 2024, it would be surprising to see construction begin before 2026 given the complexity of such an infrastructure. For the moment, the construction of this underground reservoir in Chomedey is estimated to cost around $60 million.

Furthermore, the City plans to launch a call for tenders in 2024 for the construction of a first underground retention basin intended to temporarily collect wastewater during heavy precipitation or melting snow in the spring.

This tank, whose volume would be 8,000 cubic meters, would be located under the parking lot of the Cartier arena in the Marigot sector.

In addition to “reducing overflows”, namely the overflow that the treatment plants are unable to treat, this infrastructure will make it possible to “increase our capacity to accommodate new constructions”, mentions Stéphane Boyer.

Remember that in 2021, the Ministry of the Environment had recorded no less than 1,219 sewage overflows on the territory of Île Jésus, equivalent to 3.3 overflows per day in the waterways.

This underground basin planned for Laval-des-Rapides is the first of three reservoirs of its kind to be developed in Laval.