Water Resource Management and Infrastructure in Spain

1. Water as a Resource

1.1 Consumptive Water Use

Irrigated agriculture accounts for 80% of water consumption, alongside usage in economic sectors, households, and municipalities. Average water consumption was recorded at 160 liters per inhabitant per day in 2006.

1.1.2 Non-Consumptive Water Uses

These include fisheries, aquaculture, hydropower, navigation, and nautical sports.

1.2 The Water Balance

Water resources, particularly rainfall, face a total volume deficit of approximately 3,000–4,000 hm³ annually due to several factors:

• 1.2.1 Irregular distribution of resources: Rivers exhibit strong seasonal and interannual irregularity, as well as uneven spatial distribution.
• 1.2.2 Irregular distribution of demand: The most dynamic economic and demographic areas, such as the Mediterranean, face significant water scarcity.
• 1.2.3 Infrastructure limitations: Issues regarding dam efficiency and water losses.

1.3 Waterworks

Infrastructure is built to regulate water resources and improve water quality.

1.3.1 Works to Regulate Water Resources

a) Rivers: Regulated by dams, reservoirs, canals, and diversions.

• a.1 Dams: Artificial storage behind barriers to cross streams. Most private dams are for electricity production, while others supply agricultural, urban, and industrial needs. Challenges include sediment accumulation, technical non-viability, and social or environmental disruption.
• a.2 Distribution channels: Over 15,000 km of channels exist, though some stretches suffer from significant leakage.
• a.3 Transfers: Water transfers between surplus and deficit basins, which have generated numerous conflicts.

b) Other water resources:

• b.1 Pyrenees lakes: Located at altitudes over 2,000 meters to produce hydroelectric power.
• b.2 Seawater: Spain leads the EU in desalination with over 700 plants, though this faces challenges regarding high energy consumption and brine elimination.

1.3.2 Works to Improve Water Quality

Includes the implementation of sewage treatment plants.

1.4 Water Policy

Policy focuses on two main purposes: regulation and water management planning.

2.1 River Basin Management Plans

These determine the specific infrastructure needs for each basin.

2.2 National Hydrological Plan

Coordinates basin plans and designs general measures. Objectives include:

• Achieving hydrological self-sufficiency through new hydraulic works.
• Reducing water consumption.
• Improving water quality through purification and sewage treatment.
• Flood prevention and drought mitigation.
• Boosting research and technological innovation.