Water resources and management
Connect water stores and use to physical supply, demand and water security, then evaluate resource and demand-management strategies.
Exam scope and assessment notes
Cambridge International AS & A Level Geography 9696, 2027–2029 syllabus, Topic 5. Across every topic, practise reading both quantitative and qualitative geographical resources, describing patterns before explaining them, evaluating evidence and producing a structured, supported conclusion. These original explanations and self-checks are independent study support, not Cambridge questions, official marks or grades. Centre-selected named examples and detailed case studies still need course-specific evidence packs. Full timed mock papers, official marking or grade prediction, and human subject-teacher review are not provided. Fieldwork is not assessed in this syllabus, but this site does not collect or supervise primary data.
Before you begin
- Cambridge recommends prior Geography at approximately Cambridge IGCSE or Cambridge O Level. Read the source and its scale before explaining patterns; support evaluation with relevant evidence.
Work on paper. Try each question before revealing help, and explain why your method works.
Quick readiness check
Name one physical factor that can affect water supply.
What you will learn
- Compare global water resources and water consumption patterns
- Explain how people modify the water cycle and what shapes supply and demand
- Assess water security, access, scarcity and impacts
- Evaluate strategies for increasing supply and managing demand using a named-country example
Water resources vary by place, time, quality and access
Freshwater can be found in rivers, lakes and reservoirs, groundwater, ice, precipitation and recycled supplies. Its distribution is uneven; climate, geology, relief and drainage patterns affect availability. Physical scarcity means insufficient water resources; economic scarcity means people cannot reliably access available water because of infrastructure, cost or governance.
The human water cycle captures, stores, treats, distributes, uses, disposes of and reuses water. Agriculture, deforestation, urbanisation, industry, abstraction and flood management alter natural stores and transfers. Water consumption varies with income, population, agriculture, industry, tourism, season and household access.
Security depends on supply, demand and management
Water security involves reliable access to sufficient, safe water. Supply depends on physical conditions and human infrastructure such as reservoirs, transfers, treatment, desalination and recycling. Demand reflects population number and income, economic structure and seasonal use. Pollution and poor infrastructure may limit usable water even where rainfall is high.
Supply strategies include reservoirs, transfers, desalination, rainwater harvesting, grey-water use and technology for places without piped supplies. Demand strategies include prices, rationing, efficient technology and education. Evaluate costs, energy use, environmental effects, equity, water quality, conflicts, saltwater intrusion, subsidence and long-term reliability.
Sources for this lesson
Pause and explain
Why might demand management be more sustainable than building another supply scheme?
Worked example
A town receives 40 million litres of usable water each day and demand is 46 million litres. Calculate the daily deficit and suggest why this does not by itself prove physical scarcity.
Show the worked solution
- Deficit = demand − usable supply = 46 − 40 = 6 million litres per day.
- The figure shows a shortfall at the stated time and boundary.
- Check seasonal storage, transfers, water quality, access and whether infrastructure or distribution limits supply.
Answer The daily deficit is 6 million litres. The cause may be physical, economic or infrastructural, so more evidence is needed to classify the scarcity.
Try a topic test
Choose Easy, Normal or Difficult. Save your answers and open worked review after finishing.
Test this topic →From guided practice to a new situation
Write your answer and reasoning first. Use a hint only if you are stuck. The model solution is for self-checking; your written work is not automatically marked.
A city uses 600 million litres per day: 60% goes to households, 25% to industry and the rest to other uses. Calculate household and industrial use, then explain one limitation of the totals.
Give me a hint
Multiply total use by each share; retain the same units.
Compare my reasoning
- Households: 0.60 × 600 = 360 million litres per day.
- Industry: 0.25 × 600 = 150 million litres per day.
- The total may hide seasonal variation, leakage, unequal access or differences between industrial sectors.
Household use is 360 million litres per day and industry uses 150 million. Check the time period, distribution and sector definitions before drawing a wider conclusion.
Look for these in your work
- Percentages applied correctly
- Units retained
- One data limitation identified
A dry region considers desalination and water pricing to address a seasonal shortage. Compare one strength and one limitation of each.
Give me a hint
Distinguish adding supply from changing demand; consider energy, affordability and reliability.
Compare my reasoning
- Desalination can add a relatively dependable supply near a coast, but needs energy, capital and safe brine management.
- Pricing can reduce waste or fund infrastructure, but may burden low-income households unless access is protected.
- Compare seasonal volumes, costs, energy, equity, environmental effects and who can access the water.
Neither strategy is universally preferable. A robust plan uses local supply data, protects basic access and evaluates financial, environmental and distributional effects.
Look for these in your work
- Supply and demand strategies distinguished
- Benefits and costs included
- Equity and scale considered
A country proposes a reservoir, water transfers and grey-water reuse. Evaluate the package for long-term water security.
Give me a hint
Assess reliability, quality, users and environmental effects rather than counting schemes.
Compare my reasoning
- A reservoir can store seasonal flows but may displace communities and alter ecosystems.
- Transfers can redistribute water but may create upstream/downstream conflicts and depend on infrastructure.
- Grey-water reuse can reduce demand for treated freshwater; evaluate safety standards, acceptance, maintenance and the volume saved.
The package can diversify supply and reduce pressure, but success depends on reliable operation, water quality, environmental safeguards, equitable access and local evidence on volumes and demand.
Look for these in your work
- All three measures evaluated
- Risks and users included
- A conditional conclusion
Common mistakes
- Equating freshwater presence with reliable safe access
- Confusing physical and economic scarcity
- Assuming a reservoir or desalination plant has no environmental cost
- Treating household use as the only source of demand
- Calling a strategy successful without comparing outcomes and affected groups
What can you explain now?
A region has water in a nearby river, but people lack treatment and pipes. Is the barrier necessarily physical scarcity?
Compare with the explanation
No; it may be economic or infrastructural scarcity
Usable access depends on infrastructure and management as well as water in the environment.
After trying it yourself, choose your next review. This is your self-assessment.
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Make it stick
Distinguish water scarcity from water insecurity, then compare one supply strategy with one demand strategy.
If you needed the solution, close it and solve the problem again from a blank page. A correct answer is stronger when you can explain the reason for each step.