Question time for citizens

The most important facts about the Rhesi mega-project

The implementation of Rhesi is to begin at the mouth of the Rhine near Fußach.

(Bild: IRR/Hydra)

Numerous interested parties used the information evening held by the Rhesi managers in Lustenau on Wednesday to ask questions. The "Krone" has summarized the most important facts.

How much will Rhesi cost taxpayers?
It is currently expected to cost CHF 1.9 billion excluding VAT, or CHF 2.1 billion including VAT. The project costs in Switzerland and Austria are estimated at CHF 707 million each, with inflation (up to 2052) taken into account at CHF 248 million in each case. While the Austrians have to shell out 180 million francs in VAT, the Swiss only pay 70 million francs.

Why has the sum almost quadrupled since the start of planning?
The first cost estimate was made in 2011 and the legal requirements have changed since then. More attention is being paid to ecology. Furthermore, 13 years ago, the plan was only to widen the channel. Investigations then showed that the dams also needed to be renewed or renovated. Cost: 200 million francs. And inflation had not yet been factored in in 2011.

The event in the Reichshofsaal in Lustenau was well attended.

(Bild: Frederick Sams/sams-foto.com)

How long will it take to build Rhesi?
It will be around 20 years before the major project is completed. Construction will primarily take place in winter, as the risk of flooding is much lower than in summer. Work will begin with the renewal or renovation of the dams in Fußach. Only after the dams have been secured will the work for the extension be on the agenda. Around 100 meters of dam will be built within one construction week, with the construction site moving 100 meters upstream every week. The construction period in Lustenau will take between three and four years.

Why can't it be done quicker?
Basically, this is a major project for which years of preliminary investigations were necessary. The negotiations for the state treaty alone took two years. Another year will pass before it comes into force.

Can the flood protection project still fail?
Yes, if the project is not approved in the proceedings. In addition, the treaty could be put to a vote in Switzerland if a referendum is held against the parliamentary decision. Swiss citizens have 100 days to collect the necessary signatures for a referendum.

Markus Mähr, overall project manager at Rhesi, answered some of the questions from citizens.

(Bild: Frederick Sams/sams-foto.com)

How will drinking water be supplied during the construction phase?
The fact is that two thirds of the drinking water in the Rhine Valley comes from wells that draw water from the groundwater accompanying the Rhine. If construction work is carried out, the exchange of groundwater will be affected. As a precaution, the affected wells will be taken out of operation for one to three years. A new well is being built near the Ill in Feldkirch to cover the resulting gaps in supply. A new transport pipeline will be built to Mäder to ensure that the water flows towards the lowlands. There are already pipelines from there to Höchst.

What will happen to the drinking water wells that are currently located where the Rhine will later flow?
These wells are being relocated in both Switzerland and Austria. The wells in Lustenau, for example, are also affected by the relocation. These will be relocated under the bridge between Au and Lustenau, regardless of any new construction plans, as this location has emerged as the best alternative.

Will Rhesi affect the planned new construction of the link between Lustenau and Au?
No. In principle, new bridges are built slightly higher. Piers and supports can be built in the river.

The discharge capacity of the Rhine will be increased from 3100 to 4300 cubic meters per second. What happens when larger volumes of water arrive?
As the dams should not break, so-called spillways are built at certain points where overflow water can be discharged. Without controlled discharge, the potential damage would be 20 billion Swiss francs; with diversions, it would be one to two billion Swiss francs.