Plant Utilities worked example

Utility Water Treatment Cost at 68% water routed through treatment: a worked example

Suppose water routed through treatment falls to 68%. This page works the full calculation at that level so you can see exactly which result moves and by how much. Estimate water treatment cost for softened water, RO, boiler makeup, cooling tower makeup, or process utility water.

The inputs for this scenario

  • Treated water volume: 900 kgal (held at the documented default)
  • Chemical and softener cost: 3.8 $ / kgal (held at the documented default)
  • Water routed through treatment: 68 % (the input this scenario stresses; the baseline uses 95)
  • Lab testing and regeneration cost: 450 $ (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Total utility water treatment cost = treated water volume × chemical and softener cost × water routed through treatment + lab testing and regeneration cost.
  • Total utility water treatment cost works out to 2,776 $ at these inputs, and this is the headline figure for the scenario.
  • Cost per item or period works out to 3.08 $ / item at these inputs.
  • Variable utility water treatment cost works out to 2,326 $ at these inputs.
  • Fixed utility adder works out to 450 $ at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where water routed through treatment sits at 95% and the headline result is 3,699 $, this scenario comes in 24.96% below the baseline at 2,776 $.
  • It computes total treatment cost as treated volume times the per-kgal chemical rate times the fraction of water actually routed through treatment, then adds a fixed lab and regeneration charge. When the numbers land here, the stressed input is the lever to work; the walkthrough above shows exactly how much each output recovers as it climbs back toward the baseline.

Results at a glance

  • Total utility water treatment cost: 2,776 $ (headline result)
  • Cost per item or period: 3.08 $ / item
  • Variable utility water treatment cost: 2,326 $
  • Fixed utility adder: 450 $

Run it with your numbers

  • To rerun this with your own numbers, open the live Utility Water Treatment Cost calculator, set water routed through treatment to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.