Where does the treatment cost per gallon come from?

Use the permit rate, the surcharge schedule, or a prior invoice divided by its metered gallons. Enter the rate on the same basis the bill uses, then keep sampling and surcharge bills in the adders.

Why does cost per gallon fall when volume rises?

The volume times rate part is constant per gallon, but the sampling and surcharge adders spread over more gallons. At the defaults, 18,000 gal costs 4.02 cents per gallon and 45,000 gal costs 2.69 cents.

Does the target compare the total or the rate?

It compares cost per gallon, the same quantity on both sides. A total against a per-gallon target is a unit mismatch, so the share here is always per-gallon against per-gallon.

Can a small batch pass the target cost?

Rarely: the sampling and surcharge adders are the same dollars on 9,000 gal as on 45,000 gal, so the small batch carries them over fewer gallons. At the defaults, 9,000 gal costs 6.24 cents, above the 4.5 cent target.

Process Manufacturing calculator

Process Wastewater Cost Calculator

Find what a treated wastewater stream costs per gallon and in total, then compare it with the target you set. Volume drives the variable treatment cost, while sampling and surcharge adders are dollars per campaign.

What this calculator does

Loaded cost of a wastewater stream per gallon and in total, checked against the target cost you set.

Formula used

Variable treatment cost = wastewater volume × treatment cost per gallon
Total cost = variable treatment cost + sampling and labor + surcharge and overhead
Cost per gallon = total cost ÷ wastewater volume
Share of target = cost per gallon ÷ target cost per gallon × 100

Inputs explained

Wastewater Volume: Gallons sent to treatment in the period, from the flow totalizer.
Treatment Cost: Permit rate or prior bill divided by its metered gallons.
Sampling and Labor: Sampling, handling and labor dollars for the period.
Surcharge and Overhead: Surcharge, permit and overhead adders for the period.
Target Cost per Gallon: Target or budget cost per gallon for this stream.

How to use the result

Best suited to pricing an effluent stream, comparing pretreatment options, allocating treatment cost by line.
Strength-based surcharges change with pollutant load, which this volume model does not see; keep them in the adders. Blending, reuse or pretreatment projects change both the volume and the rate, so rerun with the new pair.

Current U.S. benchmarks

The producer price index for industrial chemicals stands at 336.006 (BLS, Aug 2026), up 13.3% from a year earlier. Quotes priced off last quarter's material cost miss this move.
The U.S. has 14,543 chemical manufacturing establishments employing about 911,245 workers (Census County Business Patterns, 2023).

Common questions

Where does the treatment cost per gallon come from? Use the permit rate, the surcharge schedule, or a prior invoice divided by its metered gallons. Enter the rate on the same basis the bill uses, then keep sampling and surcharge bills in the adders.
Why does cost per gallon fall when volume rises? The volume times rate part is constant per gallon, but the sampling and surcharge adders spread over more gallons. At the defaults, 18,000 gal costs 4.02 cents per gallon and 45,000 gal costs 2.69 cents.
Does the target compare the total or the rate? It compares cost per gallon, the same quantity on both sides. A total against a per-gallon target is a unit mismatch, so the share here is always per-gallon against per-gallon.
Can a small batch pass the target cost? Rarely: the sampling and surcharge adders are the same dollars on 9,000 gal as on 45,000 gal, so the small batch carries them over fewer gallons. At the defaults, 9,000 gal costs 6.24 cents, above the 4.5 cent target.

Last reviewed 2026-10-01.