Water Leak Cost Calculator

How the water leak cost calculator works

Modeled monthly litres = constant leak litres per minute × 60 × leaking hours per day × days in the modeled month. Cubic metres = litres ÷ 1,000. Hours must be between zero and 24 and days between zero and 31.

Water and sewer charges each extend the unrounded cubic metres at their entered volumetric rate and round half-up to cents. Their sum is the monthly avoidable charge. The annualized charge is exactly 12 identical modeled monthly charges, not a calculation using actual calendar months.

The repair recovery ratio in months = rounded repair cost ÷ positive monthly avoided charge. It is undefined when the modeled charge is zero. A zero repair cost with positive avoided charge gives zero months. No discounting, repair life, recurring leak or financing model is included.

Use only charges that actually vary with the leaked volume. Fixed account charges remain payable and are excluded. Sewer billing treatment, tiered rates and measured flow can differ by property. EPA WaterSense provides leak detection and water-management context; this calculator does not identify a leak or recommend a repair.

Worked example

A 0.5 L/min leak for 24 h/day and 30 days loses 21,600 L, or 21.6 m³. At illustrative water and sewer rates of 1.8 and 2.2 per m³, the monthly avoidable charge is 86.40. Twelve identical months cost 1,036.80. A 200 repair cost divided by 86.40 is about 2.315 months. A 1 L/min leak doubles the monthly charge to 172.80.

Sources and assumptions

The source material explains the underlying calculation or pricing structure. Entered prices, costs, schedules and scenario choices are your assumptions; this tool does not obtain supplier quotes or predict actual results.

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