Groundwater protection areas

This map is part of the Provincial Environmental Ordinance Zuid-Holland and contains the groundwater protection areas of the province.

The production of this map is based on the current groundwater protection areas, as established by the Provincial Council within the framework of the Provincial Environmental Ordinance Zuid-Holland. The Provincial Environmental Ordinance 2021 established a new category of groundwater protection area, the additional strategic stocks. These are areas reserved for the future supply of drinking water. The map gives an overview of the groundwater protection areas to protect the quality of groundwater with a view to water extraction for drinking water supply (zones within: water catchment areas, groundwater protection zones, drilling-free zones and additional strategic stocks). This overview is based on the Provincial Environmental Ordinance Zuid-Holland, as it applies after the adoption of the tenth tranche that entered into force on 11 November 2021. Water catchment areas are a zone of a groundwater protection area in which groundwater is extracted for public drinking water supplies. Groundwater protection zones, drilling-free zones and additional strategic reserves also form part of a groundwater protection zone, although these zones do not necessarily always exist in groundwater protection zones.

A groundwater protection area is an area designated on the basis of the Provincial Environmental Ordinance as referred to in Article 1.2(2)(a) of the Environmental Management Act, for which rules are laid down in the Provincial Environmental Ordinance for the protection of the quality of groundwater with a view to water abstraction. The designated areas are indicated on the map corresponding to the Provincial Environmental Ordinance. With regard to the protection regime, the following distinction can be made:
- Water catchment areas with the strictest regime: bounded by the line from which the groundwater in the aquifer takes a maximum of 60 days to reach the extraction points (with the exception of the dune area where the entire dune area has been retained as a water catchment area).
- Groundwater protection zones: bounded by the line at ground level from which the groundwater reaches the extraction points within 50 years, taking into account the (vertical) travel time through the soil to the aquifer package, as well as the (horizontal) travel time of the groundwater through the aquifer package.
- Drilling-free zones (the least stringent regime): these have been determined on the basis of the (horizontal) travel time of at least 50 years from groundwater to the extraction points in the aquifer package.
- Additional strategic stocks: the same protection regime applies as for drilling-free zones.