Estimate variable wastewater treatment cost from flow, energy intensity, electricity price, chemical use, residuals disposal, and other volumetric costs. The calculator separates major components, reports cost per thousand gallons, and projects annual operating expense. Use it for scenario screening and budgeting with site-specific inputs.
The main result is annual variable cost at the entered flow. The unit cost excludes fixed labor, depreciation, debt service, and costs that do not change with treated volume unless entered as a volumetric amount.
Flow-only costing may miss pollutant-load effects. High-strength wastewater can change aeration, chemicals, residuals, and disposal costs independently of volume.
At 500,000 gal/day, 1.8 kWh per 1,000 gallons, and $0.12/kWh, energy costs $0.216 per 1,000 gallons. Adding $0.85 chemicals, $0.45 residuals, and $0.30 other cost gives $1.816 per 1,000 gallons. Over 365 days, annual variable cost is $331,420.
Multiply kWh per 1,000 gallons by the marginal electricity price per kWh.
No. The calculator focuses on entered flow-dependent costs and does not add fixed labor automatically.
Yes, if you can express the usage-dependent portion consistently per 1,000 gallons.
Influent strength, temperature, process efficiency, chemical dose, and residuals production can change cost independently of volume.
Enter the number of days the facility will operate during the period, up to 366.
| Component | Unit basis | Included in total |
|---|---|---|
| Electricity | Intensity × $/kWh | Variable energy |
| Chemicals | $/1,000 gal | Variable chemicals |
| Residuals | $/1,000 gal | Variable disposal |
| Other | $/1,000 gal | User-defined variable cost |