Greywater Reuse Calculator — Formula
## How to Calculate Greywater Reuse
Greywater is wastewater from showers, sinks, and laundry (not toilets or kitchen sinks) that can be safely reused for irrigation.
### Formula
**Reusable Greywater = (Shower + Laundry + Sink) * Reuse %**
### Sources
- Showers: 20-40 gal/day per household
- Laundry: 15-30 gal/load
- Bathroom sinks: 5-15 gal/day
Greywater can reduce household water consumption by 30-50%.
Greywater is wastewater from showers, sinks, and laundry (not toilets or kitchen sinks) that can be safely reused for irrigation.
### Formula
**Reusable Greywater = (Shower + Laundry + Sink) * Reuse %**
### Sources
- Showers: 20-40 gal/day per household
- Laundry: 15-30 gal/load
- Bathroom sinks: 5-15 gal/day
Greywater can reduce household water consumption by 30-50%.
Exemplo Resolvido
A household generating 40 gal shower, 15 gal laundry, 10 gal sink daily, reusing 60% at $5/1000 gal.
- Total greywater: 40 + 15 + 10 = 65 gal/day
- Reusable: 65 * 60% = 39 gal/day
- Annual: 39 * 365 = 14,235 gallons
- Annual savings: 14,235 * $5 / 1,000 = $71