The Isar river (Munich, Germany) was straightened and walled in, and went through a recent restoration process.
Walter Binder, the retired Coordinator of Environmental Engineering of the Bavarian Water Resources Department, introduced us to the projects and guided us along the river banks.
The first ideas for the restoration started in the 1980s, when a citizen claimed for “a different river.” Since then, they had years of deep discussion with the community, resulting in the project (1995 to 1999) and execution (2000 to 2011, only in the winter).
Mr. Binder explained the three objectives intended by renaturing the Isar river: protection against floods, recovery of ecological conditions, and more public spaces for leisure.
The Isar is an alpine river, whose natural branching with gravel banks should be restored. But the engineering work was only a direction: the current configuration is a product of the river’s own dynamics. The project intended the most natural solution, that should be adapted to the limits of the built environment. The columns of the bridges are an example of this adaptation, in which stones were arranged to harmonize with the natural landscape and the protection of concrete became steps for the leisure of the population. Another example is the need for protection walls, in which engineers have created a totally disguised solution with relief and vegetation where human intervention cannot be perceived. The concrete ramps also demanded special attention, since the removal of these would be very costly. Then they had the idea to form rapids with natural stones in the surroundings, along with a passage for fish. Along the way, we have the impression of a natural river, even within the downtown area.
Another aspect highlighted by Mr. Binder was determined long before the project. A former King preserved the spaces along the river for nature and for people. “You have to think about the future,” Binder said.