What is it?
Water that is not used for drinking is non-drinking water. Nevertheless, drinking water is sometimes used for purposes other than drinking, e.g. in the home or in certain industries. Drinking water is produced by extracting groundwater or (fresh) surface water and treating it to obtain the necessary quality (see also the Drinking water ecosystem service).
Water that is used for purposes such as crop irrigation, industrial processing and power generation does not need to be of the same quality as drinking water. Therefore, although non-drinking water may originate from similar sources to those used for drinking water, it is not normally treated to the same degree. For some activities, such as the sprinkler-irrigation of agricultural land, groundwater or surface water is used in a completely untreated state.
The supply of ground or surface water is regarded as an ecosystem service.
Under the CICES classification system, non-drinking water is a provisioning service, which includes the following classes:
- Provisioning: Materials: Water: Surface water for non-drinking purposes
- Provisioning: Materials: Water: Ground water for non-drinking purposes
In order to produce sufficient drinking water, it is important that enough rainwater is able to filter into the soil to keep the groundwater table topped up. The amounts of pollution in surface water need to be kept as small as possible, in order to keep the cost of water treatment down. The cost of treatment depends on the purpose for which the water is to be used. Fresh surface water is held in reservoirs (e.g. the IJsselmeer and the Biesbosch), so that a sufficient reserve is available.
If too much groundwater is extracted for non-drinking purposes, natural habitats can dry out, potentially leading to a shortage of water for drinking. In addition, sufficient fresh water has to be retained in low-lying parts of the Netherlands to prevent salination (rising salt concentration).
The quality of our water is threatened by fertilisers (nitrate, phosphate), heavy metals, pesticides and pharmaceutical residues. As well as influencing water quality, such substances have an adverse effect on the biodiversity in surface waters.
In real life
In agricultural areas, water authorities have the power to impose irrigation bans on farmers at times of drought. In the event of a prolonged drought, the use of water for industrial processes and cooling can also be prohibited. In addition, we have both natural and artificial reservoirs for the retention of surface water for use in times of drought or poor (river) water quality. Certain industries that depend on high-quality drinking water, such as the brewing industry, have initiated programmes to promote the sustainable (re)use of soil and water.
Fresh water shortage:
- Agriculture - average year
- Agriculture - dry year
- Agriculture - extremely dry year
- Sprinkler-irrigation in an average year
- Waterlevel management in average year
- Flushing in an average year (soon available)
Fresh water distribution:
- Average flow of the River Meuse
- Average flow of and distribution across the branches of the Rhine
- Distribution points on the main water system (taps)
- Sites where surface water is extracted for industrial purposes
- National Groundwater Register (LGR) of groundwater extraction sites (soon available)
Sprinkler-irrigation of crops
- Sprinkler-irrigation: avoided reduction of crop transpiration
- Water extraction for sprinkler-irrigation: effect on groundwater seepage
- Water extraction for sprinkler-irrigation: sites where groundwater or surface water are extracted