3.5 Water stress
Water stress - Environment in EU at the turn of the century (Chapter 3.5)
Pressure on water resources affects habitats, particularly wetlands, and can lead to contamination and depletion of surface and groundwater, causing soil degradation, excessive salinity, and desertification. In the EU, the Accession Countries and the European Free Trade Association countries, total water resources amount to 1897 km 3/year, of which 16 per cent are abstracted and 5 per cent consumed (not returned to the site of abstraction).
A previous upward trend in water demand has levelled off in recent years. Industry and households have increased their efficiency in using water. The prospects for water use largely depend on future trends in agricultural use, which will be affected by developments in the Common Agricultural Policy, and the extent to which water pricing is economically efficient. Agriculture consumes far more water than other uses (approximately 80% versus 20% for urban and industrial use and 5% for cooling water).
The Mediterranean countries are the major water consumers in the EU – mainly for agricultural purposes, though development pressures in comparatively dry regions are also a factor. Estimations for future total abstractions in EU show very small increases.
Transboundary river flows make up a significant share of the resources in many countries. In Hungary for instance, freshwater from upstream countries accounts for as much as 95% of the total resource – in the Netherlands and Slovak Republic, this proportion is over 80%, while Germany, Greece and Portugal rely on imported water for over 40% of their resources. While there are international agreements to control the quantity and quality of imported water, tensions can arise, especially where resources (in upstream or downstream countries) are limited.
Flooding is the most common, and costly form of natural disaster in the Mediterranean region and in central Europe. It is also more frequent in recent years in the Rhine catchment area. There is a need for management of water resources to be closely integrated with flood protection and maintenance of biodiversity.
The number of heavily polluted rivers in the EU has declined significantly, due mainly to reductions in point source discharges of organic matter and phosphorus. The improvements have been less significant in southern and eastern Europe. The phosphorus level of European lakes has decreased markedly – but water quality in many lakes in large parts of Europe is still poor. Nitrate concentrations in EU rivers have shown little change since 1980 and the reduced use of nitrogen fertilisers in agriculture does not seem to have resulted in lower levels of nitrate. In some parts of EU, drinking water contaminated by nitrate is a serious problem, particularly where it is taken from relatively shallow groundwater sources with significant time lag in recovery. In the Accession Countries, agricultural activities are generally less intensive than in the EU. Nevertheless, there are some regions with high nitrate levels, where the rural population is dependent on heavily polluted shallow wells for drinking water.
Fertiliser consumption rose in the 1960s and 1970s and fell from the mid-1980s onwards. Phosphorus fertilizer consumption in most EU countries peaked around the early 1980s, and the use of nitrogen fertilisers peaked around the mid- to late 1980s. In the Accession Countries, fertilizer consumption has declined markedly, but may increase from its current low level due to increased agricultural production.
In the EU, a high proportion of waste water is treated before discharge: 90% of the EU population is connected to sewers and 70% to waste water treatment plants, although there are differences between the northern and southern countries. Full implementation of the urban waste water treatment Directive in the EU will decrease the discharges of organic matter and phosphorus with about two-thirds and one-third respectively. In the Accession Countries, 40% of the population is not connected to sewers and for 18% waste water is discharged untreated. The remaining 42% of the waste water is treated before being discharged into surface waters, with most waste water receiving secondary treatment to remove organic matter. Upgrading treatment plants to EU standards would considerably reduce polluting discharges; two-thirds of the organic matter and almost half of the nutrients. At the same time, the intensification of urban waste water treatment will increase the quantity of contaminated remaining sludge.
The implementation of the Nitrate Directive has been unsatisfactory in the majority of Member States and proceedings have been initiated against those that have not yet complied. Implementing the Urban Waste Water Treatment Directive has been more satisfactory, and considerable investment programmes are in place in all Member States to comply with its objectives. Achieving these objectives should further improve the state of the EU waters before the end of the century. If more stringent measures are not taken to reduce emissions from agriculture, this improvement may turn out to be too small to achieve good status in Europe’s water bodies. In the longer term, the proposed Water Framework Directive would promote integrated water management within river catchments, set an overall ecological objective and deal with other pressures not covered in existing legislation.
For references, please go to http://www.eea.europa.eu/publications/92-9157-202-0/page305.html or scan the QR code.
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