Industries can conserve water by reducing demand, improving process efficiency, repairing leaks, recycling wastewater and changing water-intensive production methods. In IB ESS Subtopic 4.2, these strategies are studied at both SL and HL, with HL requiring additional evaluation of industrial water use and impacts.
How Industrial Water Conservation Works
Water conservation reduces the volume of freshwater withdrawn and the amount of polluted wastewater discharged. Industries should first identify major water inputs, storages, flows and outputs through a water audit, then target the least efficient parts of the system.
| Strategy | Mechanism and example |
|---|---|
| Closed-loop recycling | Cooling or process water is treated and circulated repeatedly instead of being discharged after one use. |
| Wastewater reuse | Treated effluent replaces high-quality freshwater where potable water is unnecessary. Singapore's NEWater supplies highly treated reclaimed water to industries. |
| Efficient equipment | Low-flow nozzles, water-efficient washing systems and dry or recirculating cooling reduce withdrawals. |
| Leak detection and maintenance | Smart meters, pressure monitoring and regular inspections identify losses from pipes, valves and storage tanks. |
| Process redesign | Dry cleaning methods, counter-current rinsing and less water-intensive production reduce demand at its source. |
| Sustainable food production | Drip irrigation, soil-moisture sensors, rainwater harvesting and drought-resistant crops reduce agricultural water use. |
The most sustainable approach follows a hierarchy: prevent unnecessary use, improve efficiency, reuse water and treat remaining wastewater. However, implementation may involve high initial costs, energy use and technical requirements. A technocentric perspective may favour advanced recycling technology, while an ecocentric perspective may prioritize reducing production and protecting environmental flows.
