Rainwater, greywater and wastewater reuse

Non-conventional sources

Article 3 includes wastewater, rainwater, greywater, brackish water and seawater among sources other than conventional surface and groundwater freshwater resources. These sources do not share one treatment or end-use requirement.

Use the correct denominator

Green NACE: 10% of total water use from non-conventional sources. Green industrial zones: 5%. Turquoise NACE: at least 20% of wastewater recovered and reused. Turquoise zones: at least 25%. Turquoise agriculture: at least 30% non-conventional water as a share of total water use.

Questions for design

• Source availability and daily demand
• Quality criteria, permissions and responsibility for verification
• Separation of potable and reuse circuits
• Storage, level, overflow and backup supply
• Metering of production, storage and actual reuse
• Fluid compatibility of the meter, valve, seals and sensors

Rainwater and greywater footnotes

The relevant annex tables refer rainwater harvesting to the applicable Planned Areas Zoning Regulation provision. Greywater is linked to areas newly designed as of the publication date. These references should not be read as an unconditional identical retrofit requirement for every existing building.