If the images of the underwater Grotto have gone around the world, most of the damage caused to the Sanctuary of Lourdes, following the flooding of the Gave de Pau this Saturday, mainly refers to the Quai Saint-Jean dam, swept away by the raging river.
After an eventful weekend, marked by the flash flood of the Gave de Pau during the night of Friday to Saturday, the Sanctuary of Lourdes has regained its usual calm. The grotto, once underwater, was reopened to the public on Saturday evening, as were the chapels of light on Sunday at noon and the pools should follow during the week… In short, the scars of the flood have almost completely disappeared within the Sanctuary, even though, this Monday, crews were still working to clear the mud that had built up, especially in the meadow.
On the other hand, on the outskirts – and this is the “big black spot” of this flooding episode – significant damage was reported on the Sanctuaire hydroelectric dam, located on the Quai Saint-Jean. “Everything has been washed away by Gave,” breathes Sébastien Maysounave, director of the site management department (in other words, the Sanctuary's technical services, the plant, which produces half of the Sanctuary's annual electricity consumption, is still operational). But, there is almost everything to redo in terms of the dam.”
The construction site disappeared under water
Since April, work on the Quai Saint-Jean dam had begun and was due to be completed in the coming weeks. Upgrade and compliance works which essentially consisted of constructing a fish pass on the dam. However, the Gave de Pau flood came to destroy everything. “On the right bank, the construction site was well advanced, so the damage was limited,” notes Sébastien “On the other hand, on the left bank, nothing was repaired and everything was swept away.” A cofferdam was specially installed along the Gave to make the work area watertight. But today there is nothing left of it and the river flows through the site, or what is left of it, as if nothing had happened…
“On the left bank, the construction site will start practically from scratch. We will have to pay for the evacuation of the damage, then build a new bulwark and resume the work which will be enormously delayed”, says the director of technical services waste of time and money We cannot quantify it at the moment, but it will probably be several hundred thousand euros damages. In a project that already initially cost 3.5 million euros…
If this 2024 flood is not the largest known in Lourdes (3.17 meters compared to 3.49 m in 2012 or 4.75 m in 2013), it is probably the most surprising. “The water level rose by 2 meters in 4 hours, emphasizes Sébastien Maysounave. .. This is a new meteorological phenomenon to be reckoned with in the future.”