Water Resources & Management
A Thirstier World
Global water consumption has more than doubled since 1980. Three forces drive the rise: a growing world population, a richer global middle class eating more meat and dairy, and the spread of intensive farming. Geographers measure the pressure with two ideas. Water footprint tracks how much water sits behind everyday goods — one cotton T-shirt uses 2,700 litres; one beef burger uses 2,400 litres. Water security describes whether a country has enough safe water to meet its needs.
Global water demand is rising because the population is growing, diets are becoming more meat-heavy, and farming and industry are using more water per person. Water security is now a development issue, not just an environmental one.
Where the Water Goes
Worldwide, around 70% of fresh water is used for agriculture, 20% for industry and 10% for domestic uses such as drinking, washing and toilets. The mix shifts with development: HICs use a much bigger share for industry, while LICs lean heavily on agriculture. The poorest households can spend hours a day collecting water from distant pumps or rivers, time that would otherwise be spent at school or earning a living.
Big Reservoirs and Big Dams
When demand outgrows local supply, governments turn to large engineering projects. Reservoirs behind dams store winter rainfall for use in summer. The Three Gorges Dam on China’s Yangtze River is the world’s biggest hydropower project and supplies water and electricity to tens of millions. The Akosombo Dam on Ghana’s Volta River created Lake Volta, one of the world’s largest artificial lakes, and was built to supply electricity for the country’s aluminium industry.
Big dams bring real benefits — year-round water, flood control, hydro-electricity, irrigation. They also cause serious problems. The Three Gorges reservoir flooded 13 cities and 140 towns and forced 1.3 million people to move. Sediment that once fertilised downstream farms now collects behind the dam wall. Wildlife habitats are destroyed, and earthquake risk can rise where heavy water sits over old fault lines.
Not every solution needs a giant concrete wall. Rainwater harvesting — capturing runoff from roofs into household tanks — works well in places like rural India, where the monsoon delivers most of the year’s rain in a few months. NGOs help build community check-dams that slow streams and let water soak into the ground. These appropriate-technology projects are cheaper, easier to maintain and rarely displace anyone, although their scale is smaller than a national dam scheme.
Water Transfers
Some countries move water across the country to balance wet and dry regions. China’s South-North Water Transfer Project pipes water nearly 1,500 km from the wet Yangtze basin to the dry, populous north around Beijing. The UK transfers water from rainy upland Wales to the much drier Midlands: the Elan Valley reservoirs feed Birmingham through a 117 km aqueduct. Transfers can be politically and environmentally controversial: source regions worry about losing their own water, and the energy needed to pump water uphill can be huge.
Groundwater — A Hidden Crisis
Groundwater abstraction draws water from underground aquifers using boreholes. In good times this is a stable, clean supply. In northern India and the south-western United States, however, farmers have pumped so heavily that water tables are falling several metres a year. Wells run dry. Land sinks. Saltwater can creep into coastal aquifers, ruining them for drinking. Aquifers can take centuries to refill, so over-abstraction is closer to mining than to renewable use.
Big dams provide year-round water, hydro-electricity and flood control but flood farmland and homes, displace large populations and trap sediment behind the wall. Sustainability depends on weighing these against local alternatives.
Shared Rivers and Politics
Almost half the world’s land sits in transboundary river basins, and managing them is a political challenge as much as a technical one. The Nile is shared by 11 countries; Egypt, near the river’s mouth, depends on it for 95% of its water. When Ethiopia began filling the Grand Ethiopian Renaissance Dam upstream in 2020, Egypt and Sudan feared their flow would drop. Years of negotiation followed. The basic rule of transboundary rivers is that the actions of one country quickly become a problem for another.
A sustainable water future combines several strategies: efficient drip irrigation in farming (which can cut water use by half compared with flood irrigation), recycling treated wastewater for industry, rainwater harvesting in homes, repairing leaky pipes (London still loses around a fifth of its supply to leaks), and pricing water properly so heavy users pay more. Climate change adds urgency: warmer temperatures shrink mountain glaciers that feed rivers in summer, and rainfall is becoming less reliable. Water management is no longer about engineering alone — it is about choices.