Flood defused

Reservoir instead of dammed emotions

The hope in Tarrenz is that pictures like this one from 2021 will be a thing of the past.

(Bild: Daum Hubert)

The constant flooding at Tarrenzer Knappenwelt has often raised the hackles of those affected. A new project is now raising hopes that the Gurglbach will only burst its banks during heavy rainfall, as has been the case in recent days.

For many years, the Gurglbach has regularly burst its banks in the area of Knappenwelt Tarrenz. After just half a day of rain, the access road - which is also a cycle path - was often impassable. This recurring mishap has a long history. The shortened version: In the 1960s, the Imst public utility company built a reservoir there to generate electricity with the obligation to remove bed load deposits.

However, as this was not done, a biotope was created over the decades. And because sediments can no longer be deposited there, the material brought with it gradually increases the level of the Gurglbach. The power plant operator has long been willing to dredge the basin. The problem: the nature conservation authority would not allow this. Only sporadic bedload removal was permitted, subject to numerous conditions, with no prospect of sustainable improvement.

The water surface of this newly created reservoir used to be completely overgrown with vegetation. Bed load was removed here.

(Bild: Daum Hubert)

Obligation to remove the bed load from now on
However, the tension ahead of the summer with its rainy days has eased this year. "We have been working on the so-called variant C since the fall of 2023," explains Thomas Huber, head of Stadtwerke, "three variants were examined to solve the problem we were aware of and the current variant was submitted to the Office of the Tyrolean Provincial Government."

A crucial point is that we now even have the obligation to clear out the bedload trap when sufficient material has accumulated. In future, individual notifications will no longer be necessary.

Stadtwerke-Chef Thomas Huber

Last year, the three positive decisions on the "renovation of the weir system" were received. In the course of this, work was also carried out on the water level. In January, a so-called bed-load trap (demarcated using GPS) was finally installed at the Knappenweltbrücke bridge. Material removal on a scale previously only dreamed of. Huber continues: "A crucial point is that we now even have the obligation to clear out the bed load trap when enough material has accumulated. In future, individual notifications will no longer be necessary."

Certainly better than before, the municipal utilities have made a great effort, but this is not a final solution either.

Stefan Rueland, BM von Tarrenz

Village chief hopes for a "bigger" solution, however
Although this is not a flood protection project, Huber believes that an improvement can be expected due to the lower stream level. The mayor of Tarrenz, Stefan Rueland, agrees: "It's certainly better than before, the municipal utilities have made a lot of effort, but it's not a definitive solution." The head of the village is hoping for "Variant A", which involves much more extensive work and is reportedly still being examined by Josef Geisler, Deputy Provincial Governor. In the meantime, however, one has to be satisfied with "C". The numerous pairs of ducks on the newly created reservoir will do.

The acid test is currently underway anyway: it is unrealistic that "land under water" will be a thing of the past when it rains as much as it has in the past few days. However, BM Rueland saw a partial success on Monday during a local inspection: "The Gurglbach has overflowed again, but to a much lesser extent than before."