Bakenhof - Dyke relocation

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Bakenhof - Dyke relocation

Factsheet: Bakenhof - Dyke relocation

Country NL
River Name Nederrijn
Site Name Bakenhof - Dyke relocation
River Characterisation
    River typology
    Location (Lat Lon) 51.9689663046676, 5.9230899810791
    Altitude lowland: < 200 m
    Catchment area large: > 1000 - 10000 km2
    Geology Siliceous
    National code/
    River type name
    Hydromorphological quality elements

    Biological quality elements
    Ecosystem Services
    EU Directives
    Project size 45 ha
    Approximate costs 100 000 - 1 000 000 Euros
    Synergy Recreation
    Status Realised
    Period of realization 2001-2004
    Evaluation Ecological change
    Implemented by Rijkswaterstaat & Staatsbosbeheer

    Key features of the case study

    The Bakenhof site is a chain of floodplains that have been enlarged by moving the dyke 200 metres inland. A side channel was also constructed to allow natural processes of erosion into the area. The result of this project in terms of WFD BQEs is fairly limited. Fish and benthic invertebrates were not monitored and macrophytes only scarcely occur in the side channel. The vegetation in the floodplain areas has increased greatly. A dynamic system has developed where succession is progressing steadily. To halt or set back succession large grazers have been employed. One of the remarkable features of the project is its synergy with recreation. People from the nearby city of Arnhem can and are encouraged to use the area for recreational purposes. This is done by constructing a playground and a barbecue spot in the area.

    Site description

    The Nederrijn (or Lower Rhine) is a branch of the Dutch part of the Rhine river. It starts at the city of Arnhem, near the site of this project, and continues up to the city of Wijk bij Duursteden where the river continues as the river Lek. Along the Nederrijn on the outskirts of Arnhem a number of floodplains are situated on the southern bank. On the northern bank there is an entrance to a harbour. The southern floodplains were largely cut off from river dynamics due to a laterally placed dyke. Also, river banks were fixated and groins were placed in the channel to keep it open for navigational purposes.

    Measures selection

    To increase the available natural area and to promote natural processes the dyke on the southern side of the river was relocated 200 meters inland over a reach of 1,4 kilometres. This meant that a number of previously agricultural lands were claimed for natural development. Also, a side channel was dug to increase the lateral connection to the floodplains. This side channel was created by creating two openings in the old dyke and deepening the floodplain between the new and the old dyke. This led to an artificial channel without bank fixation where natural processes like erosion and sedimentation can take place.

    Success criteria

    No clear success criteria for the project were found.

    Ecological response

    Macrophytes and phytobenthos

    Macrophytes have been monitored in the side channel for the project 'Rijn in Beeld'. The conclusions of this study where that the side channel is exceptionally poor in macrophytes compared to other study areas (e.g. Gameren & Vreugderijkerwaard). Only one macrophyte species was encountered, and only sporadically. Possible explanations for this lack of macrophytes were:

    • Nearly drying up of the side channel during summer months
    • Low flow in the side channel
    • Heavy silt deposition in the side channel, possibly related to the low flow conditions
    • Lack of nearby source populations for macrophyte colonization

    Benthic invertebrates

    Not monitored


    Not monitored

    Other biota


    Vegetation monitoring shows a great deal of changes throughout the time. Clear is that the creation of the side channel and the relocation of the dyke have led to a greater diversity in habitats, and with that a greater diversity in species. At the same time the species vary greatly throughout the time. In monitoring in 2003 and 2009 a total of 342 species were found, however only 213 were found in both monitoring periods. Also, in 2009 the total amount of species was lower then in 2003. Closer examination shows that pioneer species have disappeared, indicating succession taking place in the area. In due time this may lead to a further decrease in vegetational diversity. To set back succession large grazers have been deployed in part of the project area.

    Hydromorphological response

    Hydromorphology was not monitored specifically, though some information is available as it was used to explain the absence of water plants (see above).

    Monitoring before and after implementation of the project

    The area has only been monitored for vegetation, not for fish or macro-invertebrates. A number of datasets exist, most of which are from the KNNV, the Royal Dutch Association for Natural-history. They have had a multitude of monitoring campaigns in the Bakenhof, even prior to the dyke relocation. Data on vegetation is available for 1998, 2003-2005 and 2009. In 2009 the project Rijn in Beeld also monitored the Bakenhof side channel for macrophytes for Rijkswaterstaat.

    Socio-economic aspects

    Ecosystem goods and services

    The Bakenhof project has a major secondary function as a recreation area for the nearby city of Arnhem. To facilitate this while maintaining its function as ecological corridor a number of measures were taken. This included making parts of the area inaccessible to dogs to avoid unpleasant confrontations with grazers. Also, a barbecue spot was made to give the people a chance to barbecue in nature. For the children a playground which fits into the style of the natural surroundings was constructed. The area is surrounded by fencing to keep the grazers in the area, but can be freely accessed by eight gates divided fairly evenly over the fenced area. The area is freely accessible, making it ideal for hikers.

    Conflicts and synergies

    The major synergy of the Bakenhof project is the coupling between nature and recreation (see above).

    Project costs

    Exact costs unknown

    Contact person within the organization

    Vereniging Vrienden Speeluiterwaard Bakenhof e-mail

    Extra background information


    Related Measures

    Related Pressures