Use of freshwater resources - outlook from EEA (Outlook 014) - Assessment published Jun 2007
Environmental scenarios (Primary topic)
Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)
- Outlook 014
Key policy question: K: Is the abstraction rate of water use sustainable?
Total water abstraction in Europe is expected to decrease by more than 10 % between 2000 and 2030 with pronounced decreases in Western Europe.
Climate change is expected to reduce water availability and increase irrigation withdrawals in Mediterranean river basins. Under mid-range assumptions on temperature and precipitation changes, water availability is expected to decline in southern and south-eastern Europe (by 10 % or more in some river basins by 2030).
The sectoral profile of water abstraction is expected to change: withdrawals for the electricity sector are projected to decrease dramatically over the next 30 years as a result of continuing substitution of once-through cooling by less water-intensive cooling tower systems. Water use in the manufacturing sector may grow significantly. Agricultureis expected to remain the largest water user in the Mediterranen countries, with more irrigation and warmer and drier growing seasons resulting from climate change.
Note: Current water availability in European river basins and changes in average annual water availability under the LREM-E scenario by 2030
Center for Environmental Systems Research (University of Kassel, Germany), 2003-2004. Dataset: WaterGAP model.
Assessment includes baseline and Low greenhouse gas emission scenarios for Europe as a whole and within range of regions.
The changes in river-flow and groundwater recharge are expected to vary between regions, and to depend critically on the degree and types of climate change.
The following developments are expected for water availability forecasts
- Under the climate change assumptions outlined above (i.e. an increase in global average temperature over pre-industrial levels of 1.3 ?C by 2030 and 3.1 ?C by 2100), changes in average water availability in most European river basins are estimated to be relatively small over the next 30 years. Increases in annual run-off are expected for several river basins in northern Europe as average precipitation increases.
- In contrast, average run-off in southern European rivers is projected to decrease with increasing temperature and decreasing precipitation. In particular, some river basins in the Mediterranean region, which often already face water stress, may see decreases of 10 % or more below today's levels by 2030 (see Map 4.4). In the longer term, changes in water availability are likely to develop more noticeably, making the general developments expected above more pronounced.
While large decreases are expected in water withdrawals for cooling purposes in electricity production across Europe, there is considerable variation in the water use outlook of different regions and sectors (i.e. households and domestic purposes, manufacturing, cooling for electricity production, and agriculture and irrigation).
The following developments are expected for water use forecasts:
- Under the baseline scenario assumptions, water withdrawal across Europe is expected to decrease by about 11 %, to less than 275 km3 per year by 2030 (from about 300 km3 in 2000).
- Agriculture accounts for about one-third of the total water abstraction in Europe, used mostly for irrigation. The amount of irrigation water needed per crop and hectare depends mainly on soil and climate conditions, and on the efficiency of the irrigation systems. Estimates of future water abstraction for agriculture are closely correlated to estimates of the future area under irrigation. Under baseline assumptions, this is expected to increase by 20 % or more by 2030 in southern Europe, the EU candidate countries, and in Hungary, Malta, and Cyprus, while remaining more or less at current levels in other European countries.
- Large decreases in water withdrawal for electricity production are likely. Many older power stations rely on once-through cooling systems, and newer plants are expected to replace many of these over the next 30 years. The newer plants usually operate with tower cooling systems, which should result in substantial reductions, of 50 % or more, in water withdrawal, despite an expected near doubling of thermal electricity production in Europe between 1990 and 2030.
- The development of water use in households varies considerably across Europe. On average a quarter of European water abstraction is for use in the 'domestic sector', which includes households and small businesses. The future water demand of this sector is highly uncertain and will depend on a wide range of factors, including the incomes and sizes of households (water use per person usually increases with income and with fewer people per household), the age distribution of the population (water use varies considerably between different age groups), tourism and water pricing (high water prices reduce the demand for water in households, but the relationship between prices and use is highly variable). Another important factor is technological change, which generally increases the water-use efficiency of household appliances, and thus reduces total water withdrawals.
Regional features for fresh water use trends (water withdrawal forecasts) are expected the following:
- Water withdrawal in northern Europe is dominated by electricity production, and its share is expected to decrease substantially (see above). In contrast, withdrawal for manufacturing is likely to play a much larger role, despite increased water-use efficiency with technological change. And technological improvements in water-use efficiency are expected to lead to a further decrease or at least a stabilisation of average water use by households. Agricultural water withdrawal is relatively small, and may even decrease further with changing climate conditions, technologically-improved irrigation systems and a more or less constant area under irrigation.
- Water withdrawal for irrigation is the largest share of overall water abstraction in southern Europe and will be in future. Continuously improving efficiency in irrigation water use decreases water withdrawal per unit irrigated, but the savings are offset by an increase in the utilised irrigated area, leading to an increase of more than 15 % in withdrawals for agriculture (utilized irrigated area is assumed to expand by more than 20 % by 2030). However, even if the area under irrigation remains constant over the next 30 years, changing climate conditions alone are estimated to increase irrigation requirements by around 5 %. In the other main water-use sectors (electricity, manufacturing and domestic) the dynamics in southern Europe are expected to be similar to those in northern Europe, i.e. large decreases in withdrawals for electricity production and some increase for manufacturing.
New EU Member States:
A major uncertainty in the new EU Member States is future domestic water use.
- Water use per capita in households decreased markedly during the 1990s in all the countries expects Malta and Cyprus. Assuming that water use per person rises gradually to the level of other EU countries by 2030, total water abstraction by households may increase substantially (by as much as 74 %) despite decreasing populations and more water-efficient household appliances (average water use in these countries in 2000 ranged from about 40 m3 per person per year (Baltic countries) to more than 100 m3 per person per year (Cyprus) compared with the EU average of about 125 m3 per person per year).
- If water use per capita were to remain at 2000 levels instead of rising to the current EU average, domestic withdrawals would be only about half of the values projected for 2030 (i.e. total domestic water use would actually be less than today). This range (i.e. small decreases to major increase) highlights the large uncertainty in water-use projections, but also suggests avenues for future water savings in this and other regions.
- Water use in electricity production in the new EU Member States is likely to follow a similar dynamic to that in northern and southern Europe, i.e. marked decreases as power plants that rely on once-through cooling systems are replaced. As in other European regions, water use in the manufacturing sector is expected to increase with increasing economic activity. Agricultural water use is expected to remain more or less constant, as the adverse effects of climate change in this region are estimated to be of the same order of magnitude as the water savings expected from more efficient irrigation systems.
EU candidate countries:
- Changes in water use in the EU candidate countries are very dynamic; while total abstraction is expected to decline in most of Europe, they are expected to increase significantly in these countries (primarily in Turkey).
- The trend for withdrawals for manufacturing is expected to be similar to that in the rest of Europe, but somewhat more pronounced as economic activity is assumed to grow more quickly (in relative terms). In the domestic sector, Turkey is expected to experience marked increases because of continuing population growth (23.5 million more people by 2030) and increased per-capita water use (current per-capita use in households is about half the EU average). Water withdrawals may also increase somewhat in the agricultural sector, due to drier and warmer climate conditions and an expected rise in the area irrigated of around 20 %. Combined with the use of more water-efficient irrigation systems, overall water withdrawal increases for irrigation are estimated to be about 10 %.
Water stress trends are expected:
- If water withdrawal for electricity production plummets as assumed, water stress, particularly in the central European river basins (Rhine, Elbe), is expected to decrease significantly over the next 20 to 30 years. Indeed most large European river basins are likely to see decreasing levels of water stress over the next 30 years. The situation is different in river basins in the Mediterranean countries, where the interplay between decreasing water availability as a result of changing climate conditions and increasing water withdrawals for irrigation and manufacturing (and, in Turkey, for domestic use) is expected to lead to higher level of water stress (prominent examples are the Spanish rivers of Guadalquivir and Guadiana, and the Kizil Irmak in Turkey).
- A possible increase in water stress in general would also pose an increased risk on food production in drought-prone regions. Expanding irrigated areas in already water-stressed regions may deteriorate the ecological and chemical status of freshwater bodies in these areas in two ways: increased water abstraction may increase water stress levels, and agricultural return-flows may have a higher pollution load which could further decrease water quality. This underlines the indirect yet close linkages between water quality/quantity issues and agricultural policies.
- Another important dimension to water stress is the changes in intra-annual variability of water availability and abstraction, which may result in changes in the frequency of droughts and floods. Recent extreme weather events have been seen as a harbinger of future conditions, but research so far has fallen short of providing proof of a causal link to climate change. Nevertheless it has been argued that increases in precipitation and changing snow-melt patterns are likely to increase flood risk in northern Europe, and that continuing high water abstraction paired with the expected reduction in rainfall may lead to more frequent hydrological droughts in southern Europe.
Low greenhouse gas emission scenario
- Under a low greenhouse gas emissions scenario, temperature increases and precipitation changes are expected to occur at a slower rate than under the baseline scenario. Thus, the general pattern of change in water availability in a low emission scenario is expected to be nearly identical to the baseline pattern, but marginally smaller (the changes by 2030 differ by roughly 10 %). Thus, the expected impacts of different climate policies on annual river run-off are relatively small in the short and mid-term, mainly because of the enormous inertia of the global climate system. However, in the longer term, initiatives and policies that effectively mitigate severe climate change should also mitigate associated changes in water availability.
Under the low greenhouse gas emissions scenario, reductions in water withdrawal would be even more pronounced (by up to 10%), as fossil fuel power is replaced by renewable energy sources that are not cooling-intensive. However, water consumed (the part of the withdrawal that is not returned to the river) is projected to increase somewhat under both the baseline and the low emissions scenario, since evaporation is about twice as high in newer tower-cooling plants than in once-through cooling systems.