The Saone and the Rhone appear in yellow, this Tuesday night, in Lyon and upstream of the capital of the Gauls on the maps of Vigicrues, a site managed by the Central Hydrometeorological Service and support for flood prediction (Shapi) . Yellow, for yellow surveillance: this classification indicates a risk of flooding generating overflows, on a scale with four levels ranging from green (no surveillance required) to red (risk of a major crisis). However, caution is required for activities along the waterways in question.
“Flood wave in the upstream basin”
Continuously increasing for several days, the level of the Saone should increase even more in the next few hours. “The propagation of the flood wave generated in the upstream basin has a lasting effect on the increase in levels in the stretch of the Saone in Lyon,” says Vigicrues.
At the Pont-la-Feuillée station (Lyon 5), the river water level was 3.97 meters on Tuesday at 6 pm It could be at 4.08 m this Wednesday, February 3 at 5 in the afternoon. This is the so-called central forecast, between a low hypothesis (3.97 m) and a high hypothesis (4.18 m). Levels away from historical floods: 6.50 m in 1955, 4.60 m in 2018 and 5.59 m in 2001 …
In Lyon, the slight flooding of the Rhône could fluctuate slightly but, in general, stabilize. At Pont Morand, the river reached 2.62m on Tuesday at 6pm (up from 2.72m on January 31). Far from the levels observed in the same place, in January 2018 (3.53 m) and, especially in November 1944 (6.02 m).