Estimate the volume of wastewater your home, business, or facility generates per day and per month — essential for septic, sewer, and treatment plant sizing.
Typical residential water use is 60–80 gallons per capita per day in the U.S. About 80–90% of indoor water use returns to the sewer as wastewater (outdoor irrigation, evaporation, and consumption account for the rest).
| Source | Gallons/day |
|---|---|
| Single-family home | 200-300 |
| Apartment (per unit) | 100-200 |
| Office (per employee) | 15-20 |
| Restaurant (per seat) | 25-50 |
| Hotel (per room) | 100-200 |
Accurate wastewater estimates are essential for sizing septic tanks, leach fields, lift stations, sewer pipes, and treatment plant capacity. Undersized systems back up; oversized systems waste capital and accumulate solids.