My Water Stinks! What Can I Do?

First, You Must Learn a Little About Your Nose

Once you smell certain things, your sense of smell is dulled for a short while, making it difficult to make accurate judgements. For example, if you were blindfolded, smelled gasoline, ate a piece of onion, and were told it was an apple, you likely wouldn’t be able to tell the difference because your sense of smell would not be functioning properly. (Your sense of taste wouldn’t work well either—smell and taste are closely related and influence each other!)

Step 1: Play Detective

The best time to locate the source of an odour is after you’ve been away from home for a few hours—this allows your nose to “reset” and become sensitive to the smell again.

Test your untreated outdoor water:
Go to an outdoor spigot where raw, untreated water flows. Turn it on, let it run for a few minutes, and then smell the water.

  • If it smells, you’ve found the source.

  • If it doesn’t, the odour may be coming from inside your plumbing system.

Test your indoor cold, treated water:
Turn on a cold tap inside, let it run for a minute, and then smell the water.

  • If this water smells but the untreated outdoor water didn’t, you likely have a device (such as a cartridge filter or water softener) that needs to be cleaned and sanitized.

Step 2: Address the Cause

Cartridge or String Filters: Replace the element and sanitize the housing.

Water Conditioners: Contact your supplier for sanitization instructions. If you rent, call the provider. You can sanitize the unit by pouring hydrogen peroxide or chlorine bleach into the brine well of the salt tank and regenerating the unit. Always confirm the correct dosage with a professional.

Step 3: Check Your Hot Water

If the cold water smells fine, test the hot water.

  • If it smells, the likely culprit is the sacrificial anode in your water heater. A deteriorating anode can release hydrogen sulphide gas, causing a “rotten egg” smell.

  • Solutions include replacing the rod with an aluminium-alloy version or removing it entirely (note: removing the rod may void your warranty).

To replace the anode:

  1. Locate it on top of the heater (under a tin cover and insulation).

  2. Shut off heat and water supply.

  3. Use a 1 1/16" socket to remove the plug while someone stabilizes the tank.

  4. If the rod is mostly intact but corroded, replace it. If part of it has fallen into the tank, fish it out.

  5. Before sealing, pour ~2 pints of chlorine bleach into the tank to kill any remaining bacteria.

Step 4: If the Raw Water Smells

Determine the cause and severity:

Minor, Musty Smell

  • Install a point-of-use carbon filter on your drinking water line, or a whole-house carbon filter.

  • Carbon removes odours through adsorption—ensure you maintain the correct flow rate for effectiveness. Replace filter media regularly to prevent bacterial growth.

Strong, Rotten-Egg Smell

  • Caused by hydrogen sulphide gas from decomposing organic deposits.

  • This gas can tarnish silver, is toxic to aquarium fish, and is flammable in high concentrations.

Treatment Options:

  1. Specialty Filters – Designed for hydrogen sulphide removal, must be recharged with chlorine or potassium permanganate.

  2. Chlorine Feeders – Inject small amounts of chlorine to oxidize sulphides before filtration.

  3. Aeration Systems – Vent gas into the air before storing and filtering water. No chemicals required, but requires more space and an extra pump.

Bottom line:

By methodically testing each source and applying the right treatment, you can pinpoint and solve most water odour issues—restoring fresh, clean-smelling water throughout your home.