After the disaster, some point to the management of dams in our country during the precipitation of recent days. On the RTL set, Damien Ernst, computer engineer and professor at the University of Liège, for example spoke of a “colossal error” in the management of the Eupen dam. According to him, this dam should normally have made it possible to control the flow of the Vesdre if it had been emptied preventively.
Questioned by our colleagues from Sudpresse, Philippe Henry returns to this management and explains himself. The Walloon Minister of Infrastructures and Mobility indicates that the IRM forecasts only spoke of “150 mm of water per m² over the entire province of Liège and over three days“. “However, the dam has a capacity of 25 million m³ and was, at that time, half full. It could therefore absorb all the expected rains”, he says. However, by Wednesday, the Eupen dam was full. “It accumulated in 48 hours 13.4 million m³ because the rains were exceptional”, recalls the regional minister.
The decision to preventively empty the dams was taken in Butgenbach and Robertville. In Eupen, the dam reaching saturation Wednesday afternoon finally had to be emptied gradually, causing an increase in flow. “If we preventively released 40 m³ per second, and even 30 m³, we would drown the lower town of Eupen. Were we going to do that when the forecasts indicated that the dam would be sufficient? In addition, the slopes of the valley of the Vesdre are steeper than those of La Warche. The water rushes down the river much faster. That’s a big difference “, justifies Philippe Henry.