Photo: BMLFUW
Groundwater
The term “groundwater” refers to water beneath the earth’s surface that fills the cavities of the earth’s crust (pores, crevices, etc.) contiguously, under more or less pressure than the atmospheric levels, and whose movements are determined through gravity and friction.
Types of groundwaterVarious types of groundwater are distinguished in accordance with the structure of the earth’s crust:
- pore groundwater (in porous bedrock and areas of gravel and crushed stone)
- crevice groundwater (in crevices and layered, non-karstic bedrock)
- karst groundwater (in karstic bedrock)
- Local thermal springs and mineral water sources are also of particular importance.
Human impacts on the groundwater
When groundwater is polluted, it recovers only very slowly, as groundwater renewal takes very long. In particular, chemicals that infiltrate into the soil are threatening.
The following impacts might be crucial:
- Nitrate, in particular from intensive soil utilisation in agriculture, horticulture and viticulture
- Pollutants from industry, commerce and transportation
- Oil from leak containers, waste water from leaking sewers, contaminated sites and landfill sites
- Exposing groundwater by removing sand, gravel and stones
Groundwater as drinking water
While 50% of the Austrian population are supplied with spring water, approximately 50% of the Austrian population get their drinking water from groundwater supplies, in part from enormous quaternary valley and basin deposits, which are also subject to intensive use by settled areas, industry, agriculture, and transport.
Such areas amount to about 13,000 km² in Austria. Since the end of 1991, the water quality in Austria has been consistently measured by private and public contractors commissioned by the Ministry of Life (BMLFUW) and the Austrian Federal Provinces.
This programme aims at monitoring the status of Austria’s groundwater, rivers and brooks as well as any trends in order to provide a reliable database that can be used to take informed countermeasures in the event that environmental burdens are identified.
Monitoring the water quality of the groundwater
The results indicate that most of the parameters are significantly below the preventive threshold values laid down with respect to the potential use as drinking water. Approximately 93 percent of the groundwater bodies examined (those comprise 96 percent of the Austrian territory) will probably reach the good chemical status.
In the remaining groundwater bodies, higher values are observed due to nitrate, atrazine and its decomposition product desethylatrazine in the groundwater. The pollution from atrazine and desethylatrazine is clearly declining as the corresponding plant protection products have been prohibited in Austria since 1995.
Countermeasures include above all increasingly groundwater-protecting farming practices such as organic farming, the abandonment of agricultural land in favour of forests, measures of extensification of agriculture in the context of the Austrian Agri-environmental Programme (ÖPUL), refraining from the use of plant protecting agents, and the like.
The water bodies of groundwater and surface waters are in contact. Regulated wastewater disposal - above all in industry and trade, but also in the water management of residential areas -, regulated waste disposal and the remediation of historical contaminated sites always mean that the groundwater is protected.
A lot has been reached in Austria in the course of the past decades due to the determination of emission thresholds for industry and trade and the consideration of the protection of water resources already in the planning stage of industrial plants, due to the further development and maintenance of sewage networks and waste-water purification plants, measures for the restoration of contaminated sites and stringent rules for the treatment and disposal of waste.
Waste water is not put back in circulation before it has been mechanically and biologically cleaned and treated to remove the nutrients to a large extent.
European Water Framework Directive (WFD) - Status quo analysis 2005
The European Water Framework Directive stipulates that waters have to be divided into stretches (= water bodies) and that, in a first step, the impacts of human activity on the water status are assessed. After that, the status has to be monitored by means of a measuring programme in order to eventually deduce measures to improve the status.
So far, the following waters have been analysed in Austria:
- 940 water bodies of running waters with a catchment area of more than 100 km² each (total length of
11,500 km).
- 62 lakes, each with a surface area of over 50 hectares
- 162 near-surface groundwater bodies which, in their entirety, cover Austria, one thermal water body, and
eight groups of profound groundwater bodies
The objective of the WFD, which entered into force in December 2000 and was transposed into Austrian law in December 2003, is to achieve a good status for all waters by the year 2015. Any deterioration of the waters has to be prevented.
02.07.2008, Lebensministerium Öffentlichkeitsarbeit