Kimberley Roelvink
Last week I was buzzy with a sustainable landscape redesign in Limburg. I was looking for solutions on the site groenblauwenetwerken.nl, this website consists out an overview of all sustainable measurements with topics like water, heat, green, air, energy and economics.
Here in the lowlands, water maintaining and storage are a large problem. Next to this, in the "randstad" there is a lack of green. So, we learn to design with these problems. I made an idea, where some parts of the road were translated into a wadi, so the rainwater is collecting for in the summer. Luckily, my boyfriend is a gardener and he asked me how did you want to do that?
He was explaining that different types of the underground have other specific characteristics. Apparently, all options which are in groenblauwenetwerken been made for clay or sand. Kerkrade probably builds on loam; naturally no water infiltration is possible, so the water will rise and wash away the substrate. So, now the question, would it be possible to build a wadi or other natural water collecting system on this location? Will the water stay and rise until the limit or will all the water spoil away and make the wadi steeper until the 0 level which is -50m?
It could be possible that the upper layer exists out of clay laying on top of the peat. The clay forms a hard layer but is not that thick. So, by spadework the underlayers are hit. Here arise the next problem. By placing the wadi, the water will reach the peat. Peat is like a sponge, in very wet periods, the layer will bulge and the total surrounding rise up, including houses, streets etc. In drought periods the peat shrink, the surroundings become hollow. The effect is that the road, houses are lower. The effect results in subsidence of houses, streets sewer and piping.
Google didn't find the answer on this particular problem, many I didn't use the write searching words. So the next step is to call a gardener in Limburg and explain this problem to find a solution. Maby they have other problems with other undergrounds, or they have other solutions.