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Leak cost calculator

"It is only a drip" is the hardest objection to argue with in words and the easiest to settle with arithmetic. Count the drips for fifteen seconds, put your own rates in, and the annual number does the persuading. Sewer is usually billed on water volume, so a leak is charged twice.

How to find it before you price it

EPA WaterSense publishes three screens that cost nothing. First, look at a cold-month bill: a family of four using more than 12,000 gallons in January or February probably has a serious leak. Second, read the meter, use no water for two hours, read it again — any movement is a leak somewhere. Third, put food colouring in a toilet tank and wait ten minutes without flushing; colour in the bowl means the flapper is passing.

The toilet is usually the answer

A silent flapper leak beats every dripping faucet on volume, and it is the one nobody hears. Dye-test every toilet in the house before you chase anything else.

Why sewer doubles the number

Most utilities meter water and bill sewer on the same volume, on the reasonable assumption that what comes in goes out. A leak inside the house is therefore charged at the water rate plus the sewer rate, and on many bills the sewer rate is the larger of the two. That is why the total on this page is usually about double what a customer expects.

Irrigation leaks are the exception: where a separate irrigation meter exists, the sewer charge does not apply. Check which meter the leak is behind before you quote the saving.

The hot-side surcharge

A drip on the hot side is billed three times: water in, sewer out, and the energy that heated it. Raising a gallon from 55 °F to 120 °F takes about 0.159 kWh at perfect efficiency, so a hot leak on an electric heater carries roughly three cents a gallon of energy on top of the utility charge. Over a year that line frequently exceeds the cost of the cartridge that would have fixed it.