The Drinking Water Taste Guide

Why does your water taste funny? Check out our taste guide.

The Taste Guide.png

On our Tips for Taps blog we have addressed strange colored water, odd smelling water, and now it’s time to investigate what it means if your water tastes funny. Whether it’s salty, moldy, or metallic tasting–the flavor of your water can tell you a lot about what’s in it.

My Water Tastes Like….

Mold or Must? Jump here.

Bleach? Jump here.

Bitter / Medicine? Jump here.

Metal? Jump here.

Rotten Eggs? Jump here.

Salt? Jump here.

Sweet? Jump here.

Mold or Must:

We often think of water as “pure“ and “fresh”–so when it tastes moldy and musty, it is pretty easy to deduce that something isn’t right.

One of the most common reasons for a moldy taste flowing from your tap is an algal bloom in the source water. Blooms are more frequent in the springtime, so you may notice musty or moldy water around that time of year. Municipal water is treated with disinfectant, so the algae will be eliminated before it gets to you tap–but the unpleasant (albeit harmless) taste may linger. Bacterial growth within your water system can also cause a moldy flavor. This is frequently from harmless iron-reducing bacteria, but keep an eye out if the musty taste is accompanied with a rotten egg smell.

For more information about algal blooms, take a look at our Tips for Taps piece here!


If your water tastes like bleach, it is probably due to elevated levels of chlorine–a chemical added to 98% of U.S. public water systems as a disinfectant. Small amounts (levels below 4 mg/L) of added chlorine are not harmful to your health. However, chlorine can be smelled (and often tasted) at just 1 mg/L. If your tap water’s bleach/chlorine taste is particularly strong, it may be due to the fact that your water supplier distributes water over vast distances and needs to add extra chlorine in order to keep the water clean over the longer travel time.

There are ways to improve the taste of your drinking water if it has a bleach or chlorine flavor. Measures you can take include:

  • Boiling your tap water for 5 minutes
  • Chilling your water in the refrigerator
  • Using an activated carbon filter (on a faucet, or a as pitcher)

    Bitter or Medicinal:

    Bitterness is most often attributed to copper in the water–usually from the corrosion of copper plumbing. It causes health issues–like stomach cramps or intestinal pain–at levels above 60 mg/L. However, it is rare that copper concentration ever reaches this level, particularly because people can both taste and smell  copper in their water at just 1.3 mg/L. This lower level still may have impacts, albeit aesthetic ones. For example, copper in your shower water can potentially add a green tinge to light colored hair.

    Another possible cause for a bitter or medicinal taste in your tap water is an elevated levels of total dissolved solids (TDS). These dissolved minerals can cause an off-putting taste, especially if they are mostly sulfates. TDS may also induce a laxative effect in humans who are new to drinking water with higher-than-normal levels of dissolved minerals.


    Iron, zinc, and manganese can all cause a metal taste in your drinking water.  While iron and manganese naturally occur in water sources, zinc may enter your tap water when galvanized plumbing corrodes. At high levels, zinc may cause nausea or vomiting. Such a concentration would be far above the threshold where people would tolerate taking a sip.. In sum, the levels of zinc in drinking water may cause a taste, but is not known to have health impacts because when it is in drinking water (which people stand to drink), the concentrations are too low to cause health effects.

    When there are elevated levels of iron and manganese in drinking water, they can cause aesthetic impacts (such as staining laundry, plumbing, and fixtures.) They can also build up in water heaters, which may need to be drained in order to remove the mineral deposits.

    Rotten Eggs:

    The taste of rotten eggs is about as unpleasant as it gets. While it can be quite alarming, a rotten egg (i.e. sulfur) taste and smell is not generally a health hazard–especially at levels commonly found in tap water. This is because at even well below dangerous levels, the taste and smell would be so offensive that most people couldn’t palate it. The causes of this off-putting taste are sulfates or hydrogen sulfide gas. For more information about these two forms of sulfur–check out our “everything-you-need-to-know” guide to sulfur!

    Ways to remove the taste of rotten eggs from your tap water include:

    • Chlorination
    • Aeration
    • Activated carbon filters


      If your water tastes salty like the ocean, the most likely reason is that it contains a high concentration of chloride ions. You’ve definitely heard of sodium chloride (it’s your everyday table salt: NaCl), but other commonly occurring chlorides are potassium chloride (KCl) or calcium chloride (CaCl). Common causes for elevated chloride levels may be due to:

      • Seawater entering your local water supply
      • Industrial waste entering the water supply
      • Melting snow and rain carry road salt into local reservoirs

        While chloride ions are the most likely culprit if your water tastes salty, sulfates may also be to blame. Because many sulfates occur naturally in certain soil and rocks, and as groundwater moves through the earth, these sulfates can make their way into the local water supply. 
        Finally, if sewage enters the water supply, sodium and chloride levels can spike, causing your tap water to taste salty.

        Water with a salty taste is not only unpleasant to drink, it can damage your pipes. Salty tasting water is not likely hazardous to humans, but in some cases it can cause diarrhea. People who are on reduced-sodium diets may want to take extra-precautions.


        Does your water have a sweet taste? Oftentimes this is due to a high concentration of naturally occurring minerals–such as calcium or iron. Sweetness may also be attributed to an imbalance in your water’s alkaline or pH levels.

        Common methods to tackle a sweet taste or odor include:

        • Aeration
        • Activated carbon filters
        • Neutralization (for pH adjustment)

          If none of these methods solve the problem, our Tap Score home water testing packages can help you find the source of the contamination, as well as provide treatment recommendations. If you have any questions regarding taste, smell, or color of your water–send our water experts an email at and they’d be happy to help you out!