3.6 Water: Identify supply issues and sustainable management of water resources.

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IGCSE Geography 0460 – Economic Development: Water Resources (Objective 3.6)

1. How water fits into the IGCSE syllabus

  • Topic 10 – Resource provision: water is one of the three essential resources in the food‑water‑energy triad that underpins economic development.
  • Topic 5 – Climate change: altered precipitation, temperature rise and extreme events directly affect water quantity and quality.
  • Topic 6 – Population: rapid urbanisation and population growth increase per‑capita demand and strain distribution systems.
  • Impacts & Evaluation (AO3): students must identify water‑supply problems, explain causes, assess social‑economic‑environmental consequences and evaluate management options.

2. Why water is central to economic development (the food‑water‑energy triad)

  • Agriculture (food) – irrigation, livestock drinking water, post‑harvest processing.
  • Industry (energy & production) – manufacturing processes, cooling, cleaning, hydro‑electric power generation.
  • Domestic use (society) – drinking, cooking, personal hygiene, sanitation.
  • Environmental health (ecosystem services) – sustains rivers, wetlands and biodiversity; underpins tourism and recreation.
  • In many regions water is the **limiting factor** for both food production and hydro‑electric power, making it the “linchpin” of the triad.

3. Common water‑supply issues (what students must be able to identify)

Issue Key causes (physical, demographic, economic) Typical impacts on development
Quantity shortage Low rainfall, high evaporation, over‑extraction, strong seasonal variability, climate‑change‑induced droughts Reduced crop yields (e.g. a 10 % fall in irrigation water ≈ 6 % drop in wheat yields in the Indo‑Gangetic Plain), limited industrial expansion, higher water tariffs, increased rural poverty
Poor water quality Industrial effluents, agricultural runoff (fertilisers & pesticides), inadequate sanitation, salinisation, acidification Water‑borne disease, loss of labour productivity, higher treatment costs, damage to aquatic ecosystems and loss of biodiversity
Unequal spatial distribution Geographical concentration of rivers/lakes, urban‑rural divide, trans‑boundary basins, weak infrastructure in remote areas Urban water stress, rural deprivation, internal migration, potential for inter‑regional or international conflict
Infrastructure deficits Insufficient dams, reservoirs, pipelines, ageing treatment plants, high leakage rates (up to 30 % in some cities) Unreliable supply, water loss, limited access for households and businesses, higher operating costs

4. Factors that influence water supply (what students must be able to explain)

  1. Physical geography – climate zone, topography, river‑basin size and storage capacity.
  2. Population pressure – growth rate, urbanisation, per‑capita demand.
  3. Economic activities – type/intensity of agriculture, industry, tourism and mining.
  4. Policy & governance – water rights, allocation rules, pricing, regulation and trans‑boundary agreements.
  5. Technological capacity – availability of desalination, water‑saving irrigation, recycling and monitoring systems.

5. Sustainable management of water resources (evaluation of options)

Management strategy Key actions Benefits for sustainability Potential limitations Evaluation note (AO3)
Integrated Water Resources Management (IWRM) Develop basin‑wide plans; coordinate sectoral use; involve government, private sector and communities. Balanced allocation, reduced conflict, protection of ecosystems. Requires strong institutions, reliable data and inter‑agency cooperation; may be slow to implement. High importance – addresses quantity, quality and distribution; data gaps can limit planning; long‑term sustainability depends on governance capacity.
Demand‑side management Water pricing, metering, public‑awareness campaigns, promotion of water‑efficient appliances. Reduces wastage, encourages behavioural change, lowers per‑capita consumption. Can be socially inequitable unless subsidies or tiered pricing protect low‑income users; effectiveness relies on public acceptance. Important for reducing pressure; limited data on actual savings; sustainability enhanced if combined with equity measures.
Supply‑side augmentation Construction of dams/reservoirs, rainwater harvesting, desalination, groundwater recharge schemes. Increases available water, supports economic growth, buffers against drought. High capital cost, possible environmental impacts (habitat loss, displacement, salinisation), energy‑intensive (especially desalination). Crucial where quantity is the main problem; data on long‑term ecological impacts may be limited; sustainability hinges on environmental mitigation.
Water‑quality protection Regulate industrial discharge, promote organic/low‑chemical farming, upgrade sewage treatment, enforce catch‑area controls. Healthier populations, lower treatment costs, improved ecosystem services. Enforcement may be weak; monitoring equipment can be expensive; compliance costs for businesses. Key for health and ecosystem sustainability; data gaps in pollutant loads affect policy; effectiveness depends on regulatory capacity.
Reuse & recycling Treat grey‑water for irrigation, recycle wastewater for industrial cooling or process water. Conserves fresh water, reduces pollution load, creates secondary water resource. Requires technical standards, public acceptance and reliable maintenance; potential health risks if standards are not met. Strong sustainability potential; limited data on long‑term reliability; success linked to institutional support and public education.

6. Case‑study template (quick‑reference for exam answers)

For each case study fill in the headings below. This uniform format helps students retrieve facts rapidly.

Field Content (example for Israel)
Location Israel (Mediterranean & arid zones)
Water‑supply problem Severe chronic shortage; >70 % of land arid.
Key statistics 30 % of domestic supply from desalination; >80 % of wastewater reused for agriculture (≈ 1 billion m³ yr⁻¹).
Management response Large‑scale reverse‑osmosis plants; national water‑recycling programme; strict water‑pricing & metering.
Outcome / evaluation Improved water security; high per‑capita water use efficiency; criticism for high energy use and cost.

Use the same structure for the other case studies (South Africa – Orange River Basin IWRM; India – Rajasthan rain‑water harvesting; Australia – Murray‑Darling water‑buy‑back; Chile – Antofagasta desalination).

7. Cross‑topic connections (linking to other IGCSE strands)

  • Climate change (Topic 5): Drought frequency and intensity increase water‑quantity stress; sea‑level rise threatens coastal aquifers (salinisation).
  • Population growth & urbanisation (Topic 6): Rapid city expansion creates distribution problems and higher per‑capita demand.
  • Development & inequality (Topic 9): Unequal access to clean water hampers human development indices and can widen regional wealth gaps.
  • Energy (Topic 7): Hydropower links water availability to electricity supply; desalination’s high energy demand illustrates water‑energy trade‑offs.

8. Evaluation checklist (skills required for exam questions)

  1. Identify the main water‑supply problem (quantity, quality, distribution, infrastructure).
  2. Explain the underlying causes using the five influencing factors.
  3. Analyse short‑ and long‑term impacts on agriculture, industry, domestic life and the environment (include at least one quantitative example).
  4. Discuss at least two management strategies, using the “Evaluation note” column to weigh benefits against limitations and AO3 criteria.
  5. Illustrate points with a case study, applying the standard template for quick recall.
  6. Make a balanced judgement on the most sustainable option for the given context, referencing governance, equity and long‑term viability.

9. Summary of key points

  1. Water is a cornerstone of the food‑water‑energy triad and is explicitly covered in Topic 10 of the syllabus.
  2. Supply problems fall into four categories: quantity shortage, poor quality, unequal spatial distribution and infrastructure deficits; each links to physical, demographic, economic, policy and technological drivers.
  3. Impacts are social (disease, poverty), economic (reduced yields, industrial limits) and environmental (biodiversity loss, habitat degradation).
  4. Sustainable management requires an integrated approach – IWRM, demand‑side measures, supply augmentation, quality protection and reuse – evaluated against importance, data reliability and long‑term sustainability.
  5. Case studies such as Israel, South Africa, India, Australia and Chile provide concrete examples of successes and challenges.
  6. When answering exam questions, follow the evaluation checklist to demonstrate knowledge, understanding and critical thinking.
Suggested diagram: Water‑resource cycle showing sources (rainfall, rivers, groundwater, desalination), main uses (agriculture, industry, domestic, ecosystem), losses (leakage, evaporation, pollution) and points of intervention for sustainable management (IWRM, demand‑side, supply‑side, quality protection, recycling).

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