Isarplan Munich

The Isar is an alpine river that until recently was turned into a canal-like channel within the city limits of Munich. The so-called Isar Plan has been implemented since 2000: The necessary flood protection and the ecological situation are to be improved and attractive open space created for the population in the surrounding Gründerzeit neighborhoods.

The final realization section is located between the Braunau railroad bridge and the Deutsches Museum. The inner-city location, the listed buildings and the numerous recreational users place particularly high demands on planning and execution here. Implementation was carried out in sections and was completed in 2011.



New life for the Isar

(Text from the information sheet "New life for the Isar",

http://www.wwa-m.bayern.de/projekte_und_programme/isarplan/doc/gesamtplan.pdf,

Author: Munich Water Management Office)



"Protection from the flood"

The city of Munich was largely able to overcome its historical fear of the Isar's floods when the Sylvenstein reservoir was commissioned in 1959, as its water retention capacity significantly buffers the formation of flood waves in the upper reaches. However, the experience of recent decades has also taught us that there is no such thing as absolute flood protection. Calculations prior to the start of the Isar renaturation prove that the existing dykes cannot withstand the current requirements of a flood event that statistically occurs every 100 years. This realization in particular led to the birth of the "Isar Plan", which, in addition to improved flood protection, also takes into account the water ecology and recreational functions

of the Isar. The old dykes are being extended and upgraded in accordance with the latest hydraulic engineering standards. Thanks to the use of environmentally friendly construction techniques, large parts of the tree population on and around the dykes have been
preserved.


"Wild river in the middle of the city"

In order to give the Isar back some of its original momentum, it is first necessary to free it from its canal-like constraints. Breaking up the banks, which are reinforced with stones and concrete, allows the river to develop its own riverbed again within controlled limits.

As can be observed in the already renaturalized areas, the widening of the river bed with flattened banks promotes the formation of diverse water structures such as gravel islands and gravel banks. This not only makes the renaturation route more attractive in terms of landscape, but also increases its ecological value. Gravel banks in particular offer different habitats for a variety of animal and plant species. Numerous small creatures and rare fish species such as grayling and nase find new habitats and an ideal nursery thanks to gravel relocation at higher water levels. Each flood also brings with it large quantities of dead wood, which is washed up on the banks of the Isar. In contrast to the past, it is left in place as far as possible as an important structural element for the development of rare insect and snail species.



"New Isar pleasure"

The Isar with its floodplains has always been one of the most popular recreational areas close to the city for the people of Munich. The desire to preserve the "Isar experience" unadulterated and to improve it where possible was one of the main concerns of the Isar Plan from the outset. Now the water landscape in the inner-city section is also more open. Flattened banks and the terraced design of the adjacent sections of the riverbank ensure a wide view of the Isar and access to the river. Purposefully placed stones in the riverbed promote the river's flow mosaic and thus encourage the creation of gravel islands.