4.2.6—Domestic water conservation
- Syllabus
- First assessment 2026
- Objective
- 4.2.6
- Level
- HL
Match Household Conservation to the Use
Each household measure works through a different lever: metering reveals use, rationing limits it, low-flush toilets reduce service demand, grey-water reuses suitable water and rain capture substitutes local supply.
Effectiveness depends on leakage, behaviour, building design and maintenance. Protect essential-use allowances and affordability so conservation does not punish households with least flexibility.
Grey-water from showers may irrigate gardens, but it should not be connected to drinking taps without treatment.
Metering; information is needed before a tariff can change behaviour fairly.
A device’s rated saving is not its real saving if leaks, maintenance or rebound use are ignored.