If you’ve never experienced smelly water, consider yourself lucky! It’s one of the most common complaints we get from our customers before they switched to Quench. It doesn’t matter if you have city water or well water, turning on your faucet and smelling a foul odor can be unpleasant…and alarming. Whether your water smells like bleach, rotten eggs, fish, or just smells ‘off,’ your initial reaction may be to think your water supply has been contaminated. That might not be the case. Don’t despair—your Quench water experts are here to help identify common drinking water smells, determine their cause, and give general recommendations on how to rid your water of unwanted odors (and taste) for good.

Locate the Source of the Odor

The first step to solving a smelly water problem is determining where the smell is coming from. Here’s a chart that can help you locate potential sources.

Common Water Odors, Causes, and Solutions

Bleach or Chemical Odor

The smell of bleach in your tap water is undoubtedly unnerving. Nobody wants the water they drink to smell and taste like a swimming pool! This smell is likely caused by high levels of chlorine, which is usually not harmful but can be unpleasant. Some of the most common reasons for chlorine odor are:

1. Public water suppliers (PWS) chlorinate water to prevent bacterial growth

The EPA (Environmental Protection Agency) requires PWS to add small amounts of chlorine to disinfect the water before it is distributed to offices and homes. Typical levels of free chlorine in drinking water are 0.2 – 2.0 parts per million (ppm), though levels can be as high as 5.0 ppm. Follow these steps to remove the odor:

  • Test your tap water to measure the free chlorine in your drinking water.
  • If it measures over 2.0 ppm, contact your water supply authority or county health department.
  • If it measures less than 2.0 ppm, your water is safe to drink but may be unpleasant to smell. Fill a pitcher of tap water and put it in the refrigerator. The odor will dissipate over a couple hours in the cool temperature.

2. Shock chlorination of a well or plumbing system

Sometimes, typically after large storms, public water suppliers will shock the municipal water supply by adding more chlorine than usual to prevent bacteria growth in the system. This practice can produce a strong chlorine odor. The bleachy smell stops when the chlorine completely dissipates within the system in your office or home. You can speed up this process by:

  • Turn on all the faucets and let the water run until the smell goes away.

3. Chlorine interacts with organic materials built up in the plumbing system

Public water suppliers add free chlorine to water to bind with contaminants (organic materials) to disinfect and prevent biofilm growth in the drinking water. Yes, biofilm is as gross as it sounds— it’s a slimy combination of bacteria, fungi, and algae. Once free chlorine combines with the contaminants, it attaches to things like bacteria in the water and generates what are called chloramines, which give off a strong chlorine odor. And the more organic materials in the water, the worse the odor will be! Remove this terrible smell from your drinking water by:

  • Run the water faucet for a few minutes and the odor should disappear.
  • If it doesn’t and you’re on a public water supply, the problem appears to be the water supply line and you should contact your water supply authority.
  • If it doesn’t and you’re on a well, the problem appears to be in your plumbing and/or well system and your entire water system should be flushed, preferably by a licensed well driller or pump installer.

Rotten Eggs or Sewage-Like Odor

Generally, a rotten egg or sewage-like odor in your water is a result of sulfur bacteria that has found its way into your water supply. This can happen in three ways:

1. Bacteria growing in the drain

Bacteria growing in the drain is the most common reason for this smell. Over time, organic matter, like food waste, will accumulate on the walls of the drain and act as a nutrient for bacteria to grow. The bacteria can produce a gas (sulfur) which smells like rotten eggs or sewage. Address this problem by following these steps:

  • Fill a glass with water from the sink that has the smell, then step away from the sink and swirl the water around inside the glass a few times. If the problem is in the drain, the tap water in the glass should not have an odor.
  • Flush and disinfect the drain by pouring half a cup of baking soda down the drain, then pour half a cup of vinegar. Wait 15 minutes, and then pour in hot tap water.

2. Bacteria growing in the water heater

Bacteria growing in the water heater can also produce a rotten eggs or sewage-like smell. Frequently, this occurs if the hot water is unused, if the water heater is turned off for a long period of time, or if the thermostat on the heater is set too low. Generally, the bacteria that produce this problem are not a health threat, however, the taste and odor can be very unpleasant. To address this problem, the following actions are recommended:

  • Make sure that hot water smells, but cold water does not. Often, the smell originates from a magnesium heating rod in the hot water tank.
  • If the heater has a magnesium rod, a licensed plumber can replace it with an acceptable alternative such as an aluminum rod.

3. Bacteria growing in the water source

If problems with the drain or water heater are ruled out, the odor may be coming from the water source. Do not use the water because it may contain harmful bacteria. To address this problem, the following actions are recommended:

  • If you have your own well, the natural groundwater chemistry may be supporting bacterial growth in the well. Shock chlorinate the well and pump out water until the chlorine odor disappears.
  • A defective or improperly located septic system may be present near your well. Contact your county health department.
  • If you have city water, contact your water supply authority or county health department immediately.

Earthy or Fishy Odor

Although earthy/fishy odors are harmless, many people are sensitive to this smell, even at a minuscule level. These kinds of odors may be due to:

1. Decaying organic matter in the drain

By far, the most common cause of this type of odor is the decaying organic matter deposited over time in the drain. Follow these steps to eliminate a fishy smell from your drinking water:

  • Fill a glass with water from the sink that has the smell, then step away from the sink and swirl the water around inside the glass a few times. If the problem is in the drain, the tap water in the glass should not have an odor.
  • To flush the drain, pour half a cup of baking soda down the drain, then pour half a cup of vinegar. Wait 15 minutes, and then pour in hot tap water.

2. Decaying organic matter in the well storage/pressure tank

The well storage/pressure tank may also be the source of the odor. Certain types of algae, fungi, and bacteria can grow in the tank, especially during warm weather, and may affect water odor. Here’s a simple step to avoid this from happening:

  • Cleaning and maintaining the storage/pressure tank periodically can prevent bacteria from growing to levels that cause odor in the water.

3. Pollution of well water from surface drainage

If the problem is in the well, shock chlorinate the well and pump out plenty of water until the smell of chlorine disappears. If the problem persists, consider installing:

If you have city water and insufficient chlorine is being used to disinfect the water, certain types of bacteria may grow in the supply line and cause these kinds of odors. Contact your water supply authority or county health department.

Gasoline or Fuel-Like Odor

While gasoline or fuel odors are rare, they are potentially very serious. If you are on a public water supply, contact both your water supplier and county health department immediately. Fuel-like odors may be due to:

1. A leaking fuel tank or underground fuel storage tank near your well

2. Discharge from factories or landfills contaminating the water supply

3. Run-off from agriculture contaminating the water supply

Stop drinking the water immediately because it may cause several adverse health consequences including anemia, increased risk of cancer, and/or liver and kidney problems. Remedial actions include:

  • Report the problem to your county health department
  • Eliminate the source of the problem
  • Install an activated carbon filtration system after determining the type and source of the chemical contaminant

Unsure of what your water smells like, but it still doesn’t smell right?

If you have city water, contact your water supply authority or county health department for steps on how to get your water professionally tested, and if needed, treated.

If you have well water, contact a licensed well driller or pump installer.

Get the Quench Fix

Drinking water odors may come from a variety of sources – most are harmless, but all are unpleasant. If the above solutions seem too complicated or time-consuming, we have one quick and easy solution – switch to a Quench filtration system!

Quench uses advanced filtration and sanitization technologies to ensure that your drinking water is free of sediment, bacteria, viruses, parasites, chemicals, and odors and off-tastes. So, stop worrying and let Quench’s state-of-the-art filtration system do the work to make your water fresh, clean, and great-tasting. Click here to learn more about our filtration advantages and to see which product is right for you.