The passage of Storm Kirk last week allowed residents of the Yzeron* basin, already seriously flooded in 2003, and its management union, to confront the systems put in place for a risky situation in real conditions.
100mm of rain was forecast last night from Monday to Tuesday, with 90mm finally falling in 12 hours. Above all, the flow rate “only” rose to 28m3/second when the protection work can, on paper, hold up to 95m3/s.
A long wait for protection
But what about, in the future, future precipitation boosted by climate change? “We have been waiting for 20 years to be protected from the vagaries of the river”recalled Jean Luc Vidalot, the representative of the Local Interest Committees, a few days ago. Considered for a long time, the limiting dam project was abandoned at the end of 2021, too heavy, requiring too much environmental compensation.
Read also on Tribune de Lyon: Francheville. The buried dam project, but the specter of Yzeron floods remains
Two years of reflection followed to culminate, today, in the relaunch of two studies prior to the development of its future Flood Action and Prevention Program (PAPI): a hydrology study to update knowledge of the risk of flooding by overflowing the Yzeron and its tributaries while integrating the effects of climate change.
Call for testimonials
To enrich this historical knowledge, Sagirc is launching a call for testimonies: memories, photos, articles, videos, maps… in a “Flood Memories” project. To participate, contact Sagirc.
The results of this study with avenues of action are expected at the end of 2025.
The second study will determine the work to be carried out: to date, eight possible development sites have been determined for possible reservoirs or flood expansion zones.
The first scenarios are scheduled for early 2026, with the first shovels in 2027.
*Oullins, Sainte-Foy-lès-Lyon, Francheville, Charbonnières-les-bains and Tassin la Demi-Lune
