Water Treament Park Het LankheetEdit profile
Water Treatment Park Het Lankheet A functional and pleasant water garden The drying up and creation of wetland habitats The climate in the Netherlands is changing: more rain falls in the winter and the summers are a lot drier. Hefty showers of rain falling in short periods. This means flood hazard and simultaneously a drying up of the landscape, because the water discharges far too rapidly to the sea. This paradoxical situation calls for creative solutions. Not only by engineers and farmers, but by multidisciplinary teams, as in this case. Historical forms of water management are arousing interest once again. The traditional irrigation of grasslands is one of the methods to store, keep and gradually discharge water. These sewage fields can also be used as natural water filters. Het Lankheet country estate Het Lankheet country estate is situated in the east of the Netherlands. It is spread over 500 hectares and its history dates back to the year 1188. The oldest relics of irrigation systems date back to the 13th century. Since the winter of 1999/2000 these historical sewage fields have been in use again. They are being used to combat the drying up, in a good counterbalance to the dairy farming business that is run on the country estate. Furthermore, through the creation of wetland habitats an effort is being made to restore the historical stream-guiding nature. In the first instance Het Lankheet was irrigated with water from the own area, but this appeared to be inadequate in combating the drying up. Hence the choice was made to also use water from the Buurserbeek situated close by. However, this water first had to be cleaned. The water in the stream is rich in nutrients because of the manure in the surrounding agricultural lands. These fertilizers are disastrous for the stream-guiding nature which is common on poor ground. Therefore a purification installation had to be erected. The Technology During the period 2005-2006 phased reed fields were constructed in 18 compartments with a horizontal through-flow. In this water park, fundamental scientific research is being undertaken until 2010 into the purification of surface water using reed filters. Research by Wageningen UR/Plant Research International in the meanwhile, has shown that special reed fields can most effectively purify the nitrogen and phosphate in major volumes of surface water. Although it does depend on the condition, that these volumes are in precise doses: corresponding to the take-up capacity of the reed. This is why experiments are being carried out with day and night frequencies, seasonal and year-round irrigation, and rainy/drought situations. The reeds are harvested annually to remove the captured matter. Hence it is a sustainable system, because the soil is not polluted. The reeds are used to produce green energy. The purified water can then be distributed via the ancient and finely meshed sewage field system of the country estate and provide a contribution in combating the drying up and nature development.By allowing the purified water to flow in an existing but dried up marshland wood, optimal conditions come about for a natural alder (Alnus) and bird cherry (Prunus padus) wood. The Design Xxxxxxx has designed the water purification park in Het Lankheet country estate. The water purification park is perceived as a main feature in the country estate: this explicitly shows that the country estate has a narrow relationship with water in all its aspects. The ‘water purification machine’ at Het Lankheet country estate formed the inspiration for making a spectacular water garden in the country estate. Every aspect in the water machine is transformed into a park element. The elements are connected by the water and a spectacular undulating and curved dyke, which acts as both the spatial backbone as well as a look-out point. A number of places in the water purification park are distinguished through objects that we have designed. Places where the water flows from the one basin to the other, are marked with a granite head at the inlet and a derrière at the outlet. A ford has been made where the supply canal crosses a sand road. A special granite head has also been designed at the inlet point of the water. The Scottish artist Xxxxxxxx has made a water feature at the end of the system. In order to show that the water is cleaner at the end of the purification process, there are some attractive ponds in the woods. This clean water will be used to revitalize the dried up alder (Alnus) and bird cherry (Prunus padus) wood. New forests are being planted in a fairytale-like atmosphere in Het Lankheet country estate. Parts of the existing forest will be transformed into a woodland garden. Some parts of the new forest are extremely wet. Bald-cypresses (Taxodium distichum) and tupelo (Nyssa sylvatica) will be planted there. A deck path (boardwalk) runs between the trees. Part of the existing forest is differentiated with bulbous plants such as the common bluebell, wood anemone and Tiarella cordifolia, and blossoming shrubs such as Amelanchier Lamarckii. The construction of the water garden has revitalized Het Lankheet country estate. This valuable historical landscape has been given a new function and has thus taken a step in the direction of a sustainable future. It’s become a modern country estate, where the past is still tangibly present. Moreover, the country estate provides space for new nature, it produces green energy and filters a highly polluted water system.