The construction of this district, called Meerhoven, started at the end of the last century. The tendency was to build in a least damaging way as possible, keeping the groundwater on level and implement a less CO2 emitting heating system. To prevent the ground from drying-out rain is infiltrated in two ways. Every house has its own infiltration unit. This means that all rain that falls on a house is not dumped into the sewer, but lead through a pipe system to a tank which soaks the water into the ground.

Rain that falls on roads and pavements is caught by so called "wadis". A "wadi" is a ditch where the water can infiltrate in the ground. Water that falls on heavily used roads is not infiltrated because of the possibility of pollution. This all helps to keep the groundwater on the necessary level. Houses built in this area are connected to a district heating system. This system is powered by several small electricity plants. By burning gas, water is heated and a dynamo produces electricity; so called "cogeneration". Hot water is delivered to the houses and is used for heating. A heat exchanger is used to get hot tap water. By combining the production of electricity and heating, less CO2 is emitted.

On the picture you see Kolden nearby a wadi and a cogeneration plant ready to continue his journey!

More information on WADI's can be found here