Post a comment on the text below

Vienna: A stepping stone approach to river   restoration

Vienna, Austria, is crossed by three main rivers (Danube,   Wien and Liesing) which were heavily modified in the 19th century to protect   the city against floods. As a result of the changes in hydromorphology,   problems with eutrophication arose. Most of the water bodies in Vienna are   heavily modified water bodies, so the environmental objective according to   the WFD is to achieve good ecological potential in most cases.

In recent years the Vienna city administration has started   to execute a series of projects on all three rivers, with the goal to achieve   good “ecological potential” of urban water bodies, to reduce eutrophication and   to enable migration for fish and benthic invertebrates, by removing migration   barriers where possible. Measures executed were targeted at restoring the   riverbed and semi-natural riverbanks, re-introducing meanders, replacing bed   drops with bed sills so as to remove migration barriers and enhancing   wastewater treatment. In improving the hydromorphology of rivers, the   administration has started activities from the outskirts of the city and moves   into the city step by step, bearing in mind that the urban sections of the rivers are more   difficult to restore partly due to the lack of space in the urban area.    For the urban stretches, master plans   are developed in each case for the entire stretch, starting the   implementation with the River Liesing (2015-2021) and continuing with the   River Wien in the next WFD period (2021-2027). The restoration is foreseen to   continue until 2027.     

River Liesing before (left) and after (right)   restoration. Photo:@MA45 Webel.