In the Walloon Region, catchment protection is under the responsibility of the SPGE and of the producers.
Nowadays, the SPGE considerably takes part in catchment protection.
We use these days ten times as much water as half a century ago. At the same time, some industrial areas demand a higher flow rate than adjacent cities. In the meantime, river contamination due to all sorts of pollutants renders the water treatment more and more expensive. The use of groundwater is therefore important.
In the natural cycle of water, we can in general terms distinguish between surface water and groundwater. In Wallonia, groundwater accounts for a significant volume and will have to meet perpetually rising needs. In order to do that, it is necessary to know its characteristics and behaviour. Protecting it is vital.
Groundwater is essentially fed by rainwater seeping into the ground. It is stocked in reservoir rocks (aquifers) at variable depths. In an unconfined aquifer, rainwater seeps into the whole surface and collects in porous and permeable rocks (sand) or in fractured rocks (limestone). However, in a confined aquifer, water is contained under an impermeable tap and its supply mainly comes from outcrop areas or from slow exchange with other aquifers located below and above. Only fossil aquifers do not regenerate, or very slowly.
As you can see, whatever the nature of the groundwater, it was vital to regulate the different surface activities. With the producers, the SPGE has an essential mission for protection, in particular as a coordinating and financing structure for the actions of the various players involved in groundwater management. Now in Wallonia, areas around water catchment are strictly regulated in order to avoid its pollution as much as possible. In Wallonia, renewable groundwater reserves are indeed estimated equal to 550 million m³ each year; this is the volume corresponding to the part of meteoric water that seeps into the ground.
Europe, particularly concerned with the protection of the environment and the improvement in quality of life, adopted a directive in December 1979 about groundwater protection.
The Walloon Region, responsible for the preservation of Walloon groundwater, complied with the European legislation by adopting in April 1990 a decree on the protection and the use of groundwater and water that can be made suitable for drinking (decree of 30 April 1990; Belgian Official Journal of 30 June 1990; p. 13183). One goal is to provide sustainable management, the most economical possible, while allowing the multiplication of uses and ensuring the safeguarding of water.
Since 2000, the Walloon Region tasked the SPGE with carrying out the protection of catchment areas together with the different water producers. Virtually all producers signed a protection service contract with the SPGE, at the end of which the SPGE carries out the measures of protection of drinking water.
Thanks to this collaborative work amongst the different players, substantial progress has been made in the official delimitation of these areas. It is a considerable advantage for our environment and for the future of one of our most invaluable asset: water.