Groundwater
Groundwater is all the water below the surface in the subsoil. Groundwater was once rainwater. When rain falls on the ground, it sinks between the grains of sand, clay, or pebbles. The rainwater sinks into the ground until it can go no deeper. For example, because it encounters an impermeable layer of clay. Or groundwater that is already there.
What is the difference between shallow and deep groundwater?
We distinguish between shallow and deep groundwater.
- Shallow groundwater is the groundwater in the upper soil layer between the surface and the first poorly permeable soil layer, such as a clay layer.
- Deep groundwater is groundwater that lies deeper in the subsoil. Deep groundwater is located between several poorly permeable soil layers.
The immediate surroundings influence shallow groundwater. Deep groundwater is influenced by a much larger area, often higher-lying areas in the country, because water flows downhill.
Who is responsible for groundwater?
- The owner of a plot of land is responsible for water management on their own plot and for the management and maintenance of their own buildings.
- The local council is the first point of contact for groundwater flooding in urban areas (villages and towns). If necessary, the local council may ask the water authority or provincial executive for advice. It is obliged to receive excess water from neighbouring owners.
- The water authority is the point of contact for groundwater in rural areas. There are many canals and other watercourses in these areas managed by the water authority. The water authority controls the water levels in the main watercourses.
- The provincial executive is responsible for:
- the general frameworks within which water authorities and local councils operate
- the quality of groundwater
- deep groundwater and withdrawals from it, for example for industry or drinking water