Residual water: one quarter of water catchments not rehabilitated
By the end of 2012, all residual flow stretches that were approved before 1992 should have been rehabilitated. According to the Water Protection Act (source: FOEN), only seven cantons have fully implemented the legal requirements from 1992 to date. In the interest of watercourses and the habitats that depend on them, the federal government is now again calling on the relevant authorities to carry out the remediation work.
Sufficient residual water downstream of hydropower plants is necessary to ensure the diverse, natural functions of water bodies: be it as habitats for animals and plants, as landscape elements or for feeding groundwater. Four years after the legal deadline, only three quarters of the catchments of hydropower plants have been rehabilitated.
There are still 250 of around 1000 necessary remediations outstanding. This is the result of another survey conducted by the Federal Office for the Environment (FOEN) among the cantons, which are responsible for implementing the Water Protection Act.
FOEN survey on "residual water remediation
The FOEN survey, which was published at the end of May 2017, paints the following picture: Basel-Landschaft and Geneva were the only cantons to complete remediation within the legal deadline by the end of 2012. Solothurn and Uri did so by the end of 2014. In Appenzell-Innerrhoden, Basel-Stadt and Schaffhausen, there are no water withdrawals requiring remediation.
All other cantons have started with the rehabilitation, they are differently advanced. Glarus, Obwalden, St.Gallen, Ticino and Vaud have already rehabilitated more than 90 % of the residual water stretches. The canton of Schwyz had already rehabilitated over 90 % at the end of 2014, but did not participate in the 2016 survey.
Aargau, Zug, Bern, Graubünden, Nidwalden, Thurgau and Zurich have carried out between 60 and 90 percent of the rehabilitations. Fribourg, Lucerne and Neuchâtel, Appenzell-Ausserrhoden, Jura and Valais have rehabilitated less than 60 percent of the residual flow stretches. However, Appenzell-Ausserrhoden, Jura and Valais have made significant progress since the last survey at the end of 2014. Of the total of 250 remediations still outstanding, a good third is accounted for by the canton of Valais and a quarter by the canton of Grisons.
The new survey also shows that many cantons had been too optimistic about the expected completion of their residual flow remediation projects in the last survey at the end of 2014. At that time, 95 % of the remediations were expected to be completed by 2017, whereas the cantons now expect just under 90 % to be completed by the end of this year. For a quarter of the still outstanding remediations, they were not able to give any deadline at all. (Source: FOEN)
The federal government is aiming for residual water remediation to be completed nationwide by the end of 2018, if possible. You can find the complete report as a PDF in this Link
