Water and Energy Resources in Spain: Management and Challenges
Item 7: Natural Resources
1. Water: A Scarce Resource
1.1. Concepts
- Watershed: Land and water aquifers providing a river’s course.
- Ephemeral River: A river with intermittent flow.
- Fluvial: Variation of river flow.
- Flood: Maximum river flow period.
- Low Flow: Minimum river flow.
1.2. Slopes and Watersheds
- Mediterranean Area: Droughts occur in summer. Autumn and winter see increased water due to melting. The Ebro River is significant.
- Cantabrian and Galician: Short rivers with constant levels. The Miño River is important.
- Atlantic Slope: Extensive basins with significant summer droughts. Major rivers include the Tagus, Duero, Guadiana, and Guadalquivir.
1.3. Water Resources
Spain’s climate affects landscape diversity. Rainfall distribution distinguishes between dry (Mediterranean) and wet (Atlantic) regions. Rainfall in wet Spain is regular, while dry Spain experiences summer droughts. Solar radiation and evapotranspiration (moisture loss) also vary. This leads to water resource distribution differences, with surpluses in some areas and deficits in others. Water management is handled by autonomous communities and the state. Water exploitation relies on dams and underground sources.
1.4. Water Uses
Key water uses are agriculture, livestock, urban, industrial, and energy.
Agricultural and Livestock
Agriculture consumes over 80% of Spain’s water, with increasing demand due to irrigation expansion. Irrigation aims to boost productivity and living standards. Issues include:
- Water resource sustainability and loss during irrigation.
- Use of highly polluting products.
- Slurry management.
- Transitioning from flood irrigation to drip or aspiration irrigation.
- Maintaining irrigation canals.
- Avoiding watering during peak sun hours.
Urban and Industrial Use
Industrial and urban water demand is less than agriculture. Industries use water for cooling, cleaning, and waste removal. Domestic use has high quality demands. Spain combines domestic, urban, and river water from aquifers. Droughts can cause supply restrictions. Problems include:
- Increased water demand due to urbanization and tourism along the Mediterranean coast.
- Water pollution from urban and industrial waste.
Solutions:
- Strict discharge controls.
- Wastewater treatment installation.
- Water reuse.
1.5. Water Management: Policies
Policies focus on water acquisition:
- Water transfers.
- Seawater desalination.
- Aquifer recovery.
- River cleanup plans.
Water Transfer Policy
Addressing unequal water distribution requires major engineering works and pumping over long distances, which is expensive and faces public opposition. Consequences include:
- Aquifer changes.
- Limits to water catchment expansion.
- Changes in sediment transport.
The National Water Plan, including the Ebro transfer, has been abandoned.
Seawater Desalination
Desalination plants are expensive due to high energy consumption. However, costs and energy use are decreasing, and the water quality is good. Spain operates plants in Almería and the Canary Islands.
Aquifer Recovery
Groundwater is extracted by wells and pumping. Consequences of over-exploitation include:
- Lowered aquifer water levels.
- Desiccation of lakes and marshes.
- Aquifer salinization due to seawater intrusion from drilling, affecting farmland fertility.
- Groundwater quality degradation from fertilizers and chemicals.
River Cleanup Plans
These plans aim to reduce water quality deterioration and achieve good ecological status through:
- Stricter control of industrial and urban discharges.
- Installation of sewage collectors and water treatment systems.
2. Energy Resources
2.1. Introduction
Spain’s economic growth has increased primary energy demand. Spain has limited energy resources, making it energy-dependent. The national energy plan aims to:
- Strengthen traditional energy sources.
- Reduce oil consumption.
- Introduce renewable energies.
- Develop energy-saving policies.
- Increase natural gas use.
2.2. Water Energy Resources
Hydroelectric power plants provide clean, renewable energy by harnessing water force. Reservoirs store water, ensuring continuous flow and regulating rivers. Spain generates significant hydroelectric power. Advantages include:
Economic benefits, although sedimentation can reduce energy capacity.
Problems:
- High initial costs due to construction and social impacts (flooding fertile valleys).
- Limited potential for expansion due to the high exploitation of Spanish rivers.