Isar-Plan: Improving flood protection and recreational opportunities by redesigning the Isar

    Solution ID
    Description of solution
    Summary (Challenges; Objectives)

    Heavy rain events in the Alps in the years of 1999, 2005 and 2013 led to major floods and substantial financial damage in the South of Germany. Such events are likely to increase with climate change. Furthermore, balancing societal and ecological priorities as well as working to remodel the densely populated inner city to implement the river restoration plan was challenging, with disagreements over the design in certain areas as well as what was feasible within the confines of the city.The Isar river restoration along 8 km in the city of Munich is a spectacular achievement in its ability to accommodate both large floods that regularly impact the area and high recreational usage with up to 30,000 people gathering in the area on warm weekends, while improving biodiversity.The project group “Isar-Plan” was initiated in 1995 during an investigation of the Munich flood protection systems and amidst an increasing demand for a “closer to nature” urban environment which can offer recreational opportunities. The project was headed by Munich City and the Bavarian Water Board and represents an unparalleled level of interdisciplinary cooperation. After preliminary studies in how to design a project that balanced the aims for flood protection, ecology and recreation, work started in 2000. The main channel was widened from 50m to 90m and a number of measures have been undertaken to restore the natural hydrological function, a near-natural appearance of the river, with ample habitat for flora and fauna and recreation areas, while at the same time ensuring flood protection of the surrounding area.In 2003 a landscape design completion was launched with public consultation and participation for the last 1.6Km stretch in the heart of the city (that needed to take into account ecological, flood protection and recreational goals). This resulted in controversial discussions and public quarrel because two near opposing projects (an urban functional design vs a total re-naturalised design) were selected as first and second prize. Finally, in 2005, both teams collaborated to provide a compromised design that encompassed the secure flood protection needed within the constraints required by the heavily built up area and a renaturalised appearance.

    Success factors / lessons learnt

    The project successfully improved protection against flooding through developing more of a natural river landscape, which allows space for the river. Indeed, a big flood in 2005 had an effect on the whole catchment area and allowed evidence to show where the restoration had mitigated flood damage. As seen through the impacts of this massive flood in other areas of southern Germany, the restoration of the river Isar has improved flood control and reduced the damage that could have been caused.The project has also benefited biodiversity through the creation of new habitats for flora and fauna and through allowing fish to move along the river where before they were impeded.The hydrological status has been also improved to achieve bathing water quality. This means that Munich inhabitants and visitors can swim in the river and benefit from the attractive landscape for many recreational activities.

    Location Latitude
    48.1146000000
    Location Longitude
    11.5593000000
    Comment on location

    Munich, Germany

    Keywords
    Ecosystem (s) impacted
    Urban
    Hazard(s) concerned
    Floods
    Other challenges
    Climate adaptation
    International classification
    Sustainable development goals addressed
    SDG6 – Clean Water and Sanitation
    Sendai Frameword priorities addressed
    Priority 3. Investing in disaster risk reduction for resilience
    Actors
    Who are the beneficiaries of the action
    surrounding infrastructure, citizens and visitors
    Contact person
    Wasserwirtschaftsamt München
    Organizations involved in the implementation of the action

    Landeshauptstadt München, Wasserwirtschaftsamt München

    Temporal aspects
    Implementation time of the action
    Less than 2 years
    Financial aspects
    Comment
    35 million euuros to restore 8km of river
    Others
    Participatory process
    Yes
    Partcipatory approaches/ community involvement

    public consultation and participation

    Risk reduction
    Feasibility
    Environment
    Society
    Economy
    35000000.00