Human geography · GCSE Geography
Water management
GCSE Geography water management: supply and demand, aquifers and reservoirs, the Colorado and Three Gorges as contested schemes, UK drought and hosepipe bans, and sustainable use.
Water stress is maths: people plus industry plus farming minus reliable rain — pipes and politics decide who gets wet.
The important bits
What you need to know
- 1
Water security is reliable access to clean water for drinking, farming and industry. Stress happens when demand exceeds sustainable supply — physically scarce (desert) or economically scarce (polluted or unaffordable).
- 2
Sources: groundwater (aquifers — slow to recharge), surface water (rivers, lakes), reservoirs, desalination (energy-hungry, Saudi Arabia and Israel), and virtual water in imported food.
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Demand sectors: domestic, agricultural (irrigation is the global giant — 70% of freshwater withdrawals), industrial (cooling, manufacturing), and tourism (golf courses, pools in arid coasts).
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Colorado River (USA): over-allocated among states and Mexico; Lake Mead falling; alfalfa and cities in desert climates; treaty politics. Shows legal rights beating physical reality.
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Three Gorges Dam (China): HEP, flood control, navigation on the Yangtze; displaced 1.3 million, sedimentation, landslides, ecosystem change. Mega-project trade-offs in one sentence each.
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UK management: reservoir networks (Kielder transfers to Tees), hosepipe bans in drought (2022), leakage from ageing pipes (Thames Water debates), SuDS in towns, metering and behaviour change.
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LIC/NEE challenges: women and girls collecting water (time poverty), cholera from untreated supplies, Nile/Euphrates upstream dams affecting downstream farmers, and climate change shifting monsoon reliability.
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Sustainable strategies: drip irrigation, grey-water recycling, reducing leakage, pricing that reflects scarcity, wetland restoration for filtration, international basin agreements, and demand management before endless supply expansion.
Quotations worth analysing
Short evidence. Real method.
“The Colorado is a legal river before it is a physical one — rights were promised for more water than reliably flows.”
Use when evaluating dams and allocation. Over-abstraction is a human choice, not only drought.
“Three Gorges generates power and controls floods — and drowned villages and changed a river’s ecology.”
Always pair benefit (HEP, flood) with cost (displacement, sediment). One-sided dam essays fail evaluation.
Go deeper
Virtual water: the hidden import
Importing tomatoes from a water-stressed country imports the water used to grow them. HICs can look water-frugal at home while outsourcing irrigation stress to Spain’s Almería greenhouses or Peru’s asparagus valleys. GCSE level: say that trade moves water as embedded food and goods. A fair answer asks who bears scarcity — exporting farmers or importing shoppers. Water-footprint thinking links food security to water management without a separate paragraph of waffle.
Go deeper
UK drought is not only a hot summer
2022’s hosepipe bans followed low rainfall plus high demand and leaky infrastructure. Southeast England is relatively dry and densely populated; climate projections suggest drier summers. Management mixes reservoirs, transfers, metering, and fixing leaks (billions of litres lost daily nationally). Soft options — water butts, drought-resistant planting — sit beside hard engineering. Evaluation: building a new reservoir takes years, floods a valley, and does not fix wasteful use. Examiners like “reduce demand first, then augment supply”.
See the idea in action
Question: evaluate a large-scale water management scheme. Scheme: Three Gorges Dam. Benefits: 22,500 MW HEP, flood protection for millions downstream, improved shipping. Costs: 1.3 million displaced, archaeological loss, sediment trapping reducing downstream fertility, landslide risk. Judgement: essential for China’s energy and flood safety at huge social and environmental price; smaller-scale efficiency might have complemented rather than replaced community costs.
Exam technique
Turn knowledge into marks
Learn one transboundary river (Colorado or Nile) and one mega-dam (Three Gorges). Split answers into supply, demand, and management — not a list of “build more reservoirs”.
Common mistakes
Do not give these marks away
- 01
Treating UK water as unlimited because it rains a lot (regional and seasonal stress is real).
- 02
Describing dams with only benefits or only costs.
- 03
Forgetting agriculture as the largest global water user.
Which sector uses the largest share of global freshwater withdrawals?
ADomestic drinking and washing
BAgricultural irrigation
CHydroelectric power generation only
DInternational shipping
Show the answer
Agricultural irrigation. Farming dominates water use worldwide. Domestic use matters in exams for LIC access stories, but irrigation is the global scale answer.
Quick questions
If this is the bit you searched
What is water stress?
When demand for water approaches or exceeds available renewable supply, or when poor quality limits use. It can be physical or economic.
Why is the Colorado River over-used?
Legal allocations were set in wetter decades; cities and farms in arid states still draw heavily. Lake Mead’s decline is the visible proof.
What is desalination?
Removing salt from seawater for drinking or irrigation. It works in rich, dry coasts but costs energy and money, so it is not a global default fix.