Ecological connection zones in the city

There are 12 ecological connection zones in The Hague. They represent an entire network of roadside plants, rows of trees, waterways with banks, bushes and shrubs. The natural areas are given the space to grow as naturally as possible.

At the beginning of 2017 the TV series 'Wildernis onder water' looked at 2 special projects in The Hague which aim to improve the ecological quality of the water in the city. Duckweed was removed from a large number of canals in The Hague in order to restore the ecosystem. The city ecologist also talks about monitoring the fish in the Haagse Beek. Watch the films on the YouTube-channel of the municipality:

    Maintaining the ecological zones

    It is extremely important that the ecological connection zones are properly maintained so that plants and animals are easily able to travel from one area to the other. These zones are maintained as naturally as possible. The most important management tasks are the:

    • trees
    • bushes
    • rough growth
    • grassland and meadows
    • swamp


    Trees are thinned out gradually in the zones. This way trees of different ages are left standing. Bushes and herbs closer to the ground get extra light through the canopy gaps. New trees can also take root thanks to the extra light. When this does not occur spontaneously, saplings are planted in these open spaces.


    Bushes will not be trimmed. Are the edges getting in the way? Then the bushes will be thinned out or removed. Natural species will be spared as much as possible to ensure a large variation in vegetation. Sometimes space is cleared to allow young bushes to grow.

    Rough growth

    Various zones will be maintained as rough growth (wild growing plants). Part of the surface is mown every 2 years. Rough growth makes a good site for birds, insects and small mammals to hibernate in the winter.

    Grassland and meadows

    Grassland and meadows are mown 1 or 2 times a year. Part of the growth is left in the winter months so that insects and animals can hibernate there.


    In some ecological connection zones swamp areas have been dug to border on the existing canals and ditches. After they have been dug they are left alone so that nature can eventually take over.

    Removing obstacles

    The city, traffic and people have a huge impact on the development of an ecological zone. Sometimes they get in each other’s way. A road which runs through a natural area can form a danger to walking and creeping animals. Often this can be solved by making small adaptations such as:

    • Small fauna tunnels under the road
      There are tunnels in the Lozerlaan and Loevesteinlaan. These tunnels are used by toads as well as hedgehogs, stoats, weasels and smooth newts.
    • Ledges under bridges
      Small mammals can safely cross this way, for example at the intersection of the Laak and the Rijswijkseweg.
    • Ecoducts
      An ecoduct (viaducts with vegetation and no traffic) enables animals to safely reach the other side of a busy road. There is an ecoduct over the Landscheidingsweg.

    Published: 9 February 2017Modified: 29 August 2019