Autostrada del Brennero Aims to Reopen South Lane After Biffis Canal Collapse

“We will seek damages from ENEL. For now, however, our primary concern is to work quickly to reopen the South lane,” said Ferdinand Willeit, president of Autostrada del Brennero, who is currently in Rome with the company’s director. He was informed by phone of the Preabocco disaster and was unable to visit the water-damaged hundred meters of A22 personally.

Progress of the Work and Road Damage

“Perhaps tomorrow (today, ed.) the overtaking lane of the South carriageway could already reopen. This could be a solution that at least ensures a smooth flow of traffic heading north.” The entire section, however, will be made accessible by Saturday morning. But how extensive are the damages?”

“We didn’t immediately worry about assessing the damage costs,” Willeit clarifies, “because there were more urgent issues. I haven’t yet read the experts’ reports, but I assure users that we are working as quickly as possible because the situation is extremely urgent. However, I repeat, we will definitely request compensation for damages from ENEL. The wave also took out the fencing and part of the asphalt.”

Causes and Urgent Interventions

Meanwhile, ENEL is working to understand the cause of the collapse of the Biffis canal bank. It seems certain that it was too full. The overtopping occurred, and the discharged water eroded the sand of the embankment that made up the old dam. Repairs and reinforcement of the walls were scheduled for next year, but given the situation, they will be brought forward.

“We have arranged an urgent contract,” explains Aldo De Bernardi, manager of the Mid-Adige plants, Aldo De Bernardi, “and the work will begin on Saturday or Sunday. The Biffis at Preabocco should be operational again within a month or by April 15, at the start of the irrigation season. The canal serves farmers in the upper part of the Verona province, and by that date, users obviously want it up and running.”

Costs and Causes of the Collapse

The costs of the work are expected to be manageable. “For repair and ancillary interventions, we expect to spend a little over one hundred million lire. But, since we’re at it, we plan to redo that entire section, ahead of the scheduled permanent repairs set for 2001.”

There has been no official statement yet on the causes. The “explosion” of the Biffis might have been caused by abnormal operation, but it’s difficult to determine which. “It’s too early to discuss,” says engineer De Bernardi. “We are analyzing data and have initiated site measurements and topographical surveys to understand possible damage caused to the Adige River. We are also evaluating the overall damages and the functionality of systems that monitor water levels and potential faults.”

Analysis and Causes of the Overtopping

An initial superficial analysis suggested backflow. A suspected blockage one kilometer downstream, where the Biffis enters the Preabocco tunnel, which is much steeper than the canal itself, could have caused a backflow that raised the water level significantly, leading to the overtopping.

“We conducted a preliminary check along the canal and found no obstructions. There were no obstacles, so it’s difficult to determine if and how the water backflowed.”

However, the breach has been confirmed, but the cause is still unknown. The water leaving the channel eroded the embankment, eating away the fill dirt that constituted the dam. The seven-meter-long concrete slabs lost their support, and the pressure of the water in the Biffis canal forced them to overturn.

The released liquid mass, though not suddenly but gradually, overwhelmed everything in its path. The vineyards from the mountains to the highway were destroyed, the fencing of the A22 was torn down, emergency lane asphalt slabs were lifted, and the area was flooded with water peaks reaching one meter high.

The flow continued into the surrounding countryside beyond the Autobrennero, approaching the railway. The landscape, to the first responders, appeared surreal: an enormous marsh with debris and uprooted plants in the middle of the lake. The damages, as can be easily imagined, are substantial. Estimates initially spoke of ten billion lire, though a final assessment has not yet been made.