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The Sweet Truth: 5 Reasons Your Water Tastes Sweet

Written by: James Smith

Updated: April 25, 2023

The Sweet Truth: 5 Reasons Your Water Tastes Sweet

Filling up glass with tap water

Does your sweeter-than-usual-tasting tap water have you worried or confused? There are a few reasons why this might happen and in this guide we explain the causes and exactly what you can do to solve the problem.

Reasons for Sweeter Tasting Water

If your tap water tastes sweet, there are a wide range of reasons that could be causing the issue. By eliminating each cause you can hopefully get to the bottom of the underlying issue affecting your water supply. These are the main issues that need to be investigated:


1. High Mineral Content

Water that has a high concentration of minerals like calcium and magnesium can taste sweet. Minerals in water are more commonly known to be responsible for "mouth feel" but in a 2007 journal titled 'Minerals in drinking water: Impacts on taste and importance to consumer health' it is stated that "...minerals can add salty, sweet, or bitter tastes to water..."

Calcium and magnesium ions in water can give it a slightly bitter or mineral-like taste, but at the same time, they can also suppress the perception of other tastes like sourness and bitterness, making the water taste sweeter by comparison.

Additionally, some people may perceive the taste of minerals in water as slightly sweet because these minerals can stimulate the same taste receptors on the tongue that are responsible for detecting sweetness. This is because the receptors for sweetness are also sensitive to metallic and mineral tastes.

It's worth noting that not everyone may perceive water with high mineral content as sweet, and individual taste preferences can vary. However, the presence of minerals like calcium and magnesium is probably the most common cause of slightly sweet-tasting water.

Well water, which commonly contains higher levels of minerals, usually has a naturally sweeter taste than municipal water.

minerals found in water

2. Algae Blooms

In some cases, sweet-tasting water may be caused by an algae bloom in the water supply. Algae can release organic compounds that have a sweet taste and odor, which can affect the taste of the water. These algae blooms are typically more common in the summer.

Some species of algae produce organic compounds called geosmin and methylisoborneol, which can give the water a sweet or earthy taste and odor.

Geosmin, in particular, is known to have a sweet taste and can be detected by the human nose even at very low concentrations. When an algae bloom occurs, the increased concentration of geosmin and other organic compounds can affect the taste and odor of the water, making it taste sweet or musty.

It's worth noting that not all algae blooms produce geosmin or other organic compounds that affect the taste of water. However, when an algae bloom does produce these compounds, they can be difficult to remove through traditional water treatment processes, which can make the water taste sweet or earthy even after treatment.

algal bloom

A dense algal bloom on a lake

3. Contaminants

This is the answer you didn't want to hear but unfortunately, in rare cases, sweet-tasting water may be caused by harmful contaminants like ethylene glycol, ethanol, formaldehyde, or glycolic acid.

  • Ethanol: Ethanol is a chemical compound found in alcoholic beverages (alcohol), but it can also be present in water due to industrial or agricultural activities. Ethanol has a slightly sweet taste, so water that contains it can taste sweet.
  • Formaldehyde: Formaldehyde is a chemical used in the production of resins, plastics, and other materials. It can sometimes be present in water due to industrial pollution. Formaldehyde has a sweet taste, so water that contains it can taste sweet.
  • Glycolic acid: Glycolic acid is a chemical used in many industrial processes, including metal cleaning, leather tanning, and textile processing. It can sometimes be present in water due to industrial pollution. Glycolic acid has a sweet taste, so water that contains it can taste sweet.
  • Ethylene glycol: This is a chemical commonly used in antifreeze, and it is toxic if ingested.

It's worth noting that water that tastes sweet is not always a sign of contamination. However, if you suspect that your water may be contaminated, it's important to contact your local water utility or health department to have it tested and treated as necessary.

Drinking water contamination


4. Chlorine

Chlorine is a chemical commonly used to disinfect water. At low concentrations, chlorine can give water a slightly sweet taste, similar to the taste of table sugar.

However, at higher concentrations, chlorine can make water taste bitter, metallic, or like bleach. The taste and odor of chlorine in water can also vary depending on factors like temperature, pH, and the presence of other chemicals in the water.

Chlorine can be reduced in water using a specialist water filter.


5. Medical Conditions

There are certain medical conditions that can alter our perception of taste, in particular our sensitivity to sweetness.

  1. Diabetes: Diabetes is a condition characterized by high blood sugar levels. People with diabetes may have an altered sense of taste and perceive foods and drinks as sweeter (or less sweet) than they actually are. This can include water, which may taste sweeter to someone with diabetes.
  2. Hyperglycemia: Hyperglycemia is a condition characterized by high blood sugar levels that can occur in people with or without diabetes. Like diabetes, hyperglycemia can alter our perception of taste and make water taste sweeter.
  3. Hormonal changes: Hormonal changes may also affect our perception of taste. For example, during pregnancy, some women may experience a heightened sense of taste and perceive foods and drinks as sweeter than usual.
  4. Certain medications: Certain medications can also alter our perception of taste and make water taste sweeter. For example, some antibiotics, antihistamines, and blood pressure medications can cause changes in taste perception.


What Steps Can Be Taken To Fix Water That Tastes Sweet?

If tap water tastes sweet, it could be an indication of an underlying issue with the water source or the plumbing system. Here are some steps that can be taken to fix tap water that tastes sweet:


1. Identify the Source

The first step in fixing sweet-tasting tap water is to determine the source of the problem. Sweet taste can be caused by a variety of factors as we discussed in the last section. Try and discount one of these at a time to identify the source.


2. Test the Water

You can test the water to identify any potential issues. You can purchase water testing kits online or contact a professional to test the water for you.

If you receive municipally treated water then your local water authority is obliged to publish tests periodically.

Just remember that these tests are only accurate for the water at the treatment plant. It still needs to make the journey through pipes to your faucet.


3. Install a Water Treatment System

Depending on the results of the water test, you may need to install a household water filter system. There are various water treatment options available, including activated carbon filters, reverse osmosis systems, and distillation systems.


4. Clean the Plumbing System

Sweet-tasting tap water can also be caused by bacteria, mineral build-up, or other contaminants in the plumbing system. It is recommended to clean the plumbing system regularly to prevent buildup and contamination.

Here's a quick guide to flushing your household water pipes.

  1. Turn off the water supply: Before you start cleaning or flushing your plumbing system, turn off the water supply to your home. This will prevent any water from flowing through the system while you're working.
  2. Open all faucets: Next, open all the faucets in your home, including the ones outside. This will allow any water that's already in the system to drain out.
  3. Drain the water heater: If you have a water heater, turn it off and let it cool down. Then, connect a hose to the drain valve at the bottom of the tank and run it outside or to a floor drain. Open the valve and let the water drain out of the tank until it's empty.
  4. Flush the system: Once the water heater is drained, turn it back on and let it fill with fresh water. Then, go to the highest faucet in your home (usually in an upstairs bathroom) and turn it on. Let the water run for several minutes until you can feel it getting colder, indicating that all the hot water in the system has been flushed out. Repeat this process with all the faucets in your home, working your way from the highest to the lowest.
  5. Clean fixtures and aerators: While you're flushing the system, remove and clean any faucet aerators and showerheads. These can become clogged with sediment and mineral buildup over time.
  6. Replace filters: If you have any water filters in your home, replace them after flushing the system. This will ensure that you're getting clean, filtered water throughout your home.
  7. Turn the water supply back on: Once you've flushed the system and cleaned your fixtures, turn the water supply back on and let the system fill up. Check all your faucets for any signs of leaks or other issues.


5. Contact Your Water Provider

If the issue is with the water source, such as high mineral content, it is best to contact the water provider to address the issue.

If you receive well water then high mineral content (especially iron) is a common occurrence. You can use a specialist water filter to target the offending minerals.

About the Author James Smith

James is the chief water geek here at His mission is to empower the consumer and allow people to take control of their health. His passion for water health is contagious, hopefully unlike your tap water!

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