The Ultimate Tap Water Taste Guide

The taste of your water is remarkably significant. In fact, aesthetics—taste, smell, color—are one of the leading reasons people choose not to drink their household tap water. But as with odor and color, aesthetic changes do not always mean your water is unsafe to drink. Understanding why your tap water might taste weird is an important part of being water wise. 

Another ultimate guide to round out our series on aesthetics, we’ve got the taste of your water covered—from bitter, metallic, plastic tasting and more—to what you can do about it.

The Complete Guide to Discolored Tap Water
The Ultimate Tap Water Odor Guide

Table of Contents:

• Why Does My Tap Water Taste Metallic?
• Like Chlorine?
• Bitter?
• Salty?
• Like Plastic?
• Dirty Moldy or Musty?
• Sweet?
• Like Rotten Eggs?
• When Should I Be Worried About Tap Water that Tastes Bad?
• When Should I Test Tap Water that Tastes Bad?
• What’s the Takeaway?

Why Does My Tap Water Taste Metallic?

Tap water that tastes metallic typically has an elevated presence of metals such as iron, zinc, and/or manganese. Additionally, low pH levels can impart an unpalatable metallic taste to your water.

Metallic Contaminants

• Iron and manganese
  Elevated iron levels are one of the most common causes of metallic tasting to your water, particularly for well owners. Iron and manganese (often in tandem) occur naturally in water sources. High levels of iron can also cause rust when it oxidizes inside your pipes, which can be visually noticeable—like leaving stains on your laundry and plumbing fixtures, or rust in your water heater.*
  
  
• Zinc
  Usually, zinc enters your tap water when galvanized plumbing corrodes. At high levels, zinc can cause nausea or vomiting, but those levels are very uncommon in drinking water. However, if you find elevated levels of zinc, you might want to look into the state of your plumbing system.
  
  
• Other Metals
  Sometimes other metals, like copper and nickel, can get into you water supply from pipe material and impart a metallic taste. However, by the time copper and nickel start affecting the taste (or color, in the case of copper) of your water, it's likely your pipes need professional attention.

*Additionally, elevated iron levels often lead to the presence of iron bacteria, particularly for well owners. While iron bacteria are not harmful to your health, they commonly cause metallic tasting water, yellow or brown colored water, and black buildup on fixtures and plumbing.

Low pH levels

Your water’s pH also plays a part in how it tastes. While a higher pH can give water a more slippery, baking soda-like alkaline taste, lower than normal pH levels (<6.5) can give water an unpleasant, sour or metallic flavor. Furthermore, acidic (lower pH) water can eat away at your plumbing, potentially causing pipes to leach metals into your water.

Is Tap Water that Tastes Metallic Safe to Drink?

Water that tastes metallic is not necessarily unsafe to drink, but it all depends on which metals are in your water. Left unchecked, certain metallic contaminants at elevated levels—like manganese, nickel, or copper—can cause health problems over time.

Similarly, elevated metals in your water could be signs of plumbing issues that will only worsen if left unchecked. Plus, the presence of metals that contribute off-tastes to water could indicate the presence of toxic metals that don’t have a flavor, like lead.

Furthermore, low pH levels in water have been linked to dental problems.

What Can I Do About Tap Water that Tastes Metallic?

Most home filtration systems (like reverse osmosis, nanofiltration, etc.) are designed to remove metal contaminants from your water. But it’s important to test your water before treating it so you can better understand the contaminants you’re facing and their filtration requirements.

You can also run your tap for a few minutes (also known as fully flushing your water system) to see if the metallic taste clears up. If so, your plumbing is likely leaching metals into your water and should be tested and inspected.

Why Does My Tap Water Taste Like Chlorine?

If your water tastes like chlorine or bleach, it’s probably due to elevated levels of chlorine (or chloramine, an alternative disinfectant compound made by combining chlorine with ammonia). Chlorine is the most common method of disinfection for public water systems in the United States.

Is Tap Water that Tastes Like Chlorine Safe to Drink?

Small amounts of chlorine (levels below 4 PPM) are not harmful to your health. Levels of free chlorine in public water supplies are typically between 0.5 and 2.0 PPM.[1] However, chlorine can be smelled (and often tasted) at just 1 PPM.

• Total Chlorine v. Free Chlorine
  Free chlorine is the amount of chlorine available to disinfect your water. Total chlorine is the sum of free chlorine and combined chlorine, or the chlorine that has combined with contaminants and their byproducts.

If you’re concerned about levels of chlorine in your water, there are strips you can use to measure the presence of free chlorine in a sample.

• Public Water Supplies
  You can call your local utility if free chlorine levels are too high or if total chlorine levels are making your water consistently unpalatable.
  
  
• Private Well Supplies
  Usually, chlorine or bleach-tasting well water has recently been shock chlorinated. Be sure to flush your system thoroughly until any odor of chlorine is no longer detectable.

What Can I Do About Tap Water that Tastes Like Chlorine or Bleach?

Pretty much any household pitcher filter that uses activated carbon will improve the taste of water that tastes like chlorine or bleach.

To remove the flavor of chlorine you can also:

• Boil your water for 5-15 minutes
• Place your water in the refrigerator for 24 hours

Why Does My Tap Water Taste Bitter?

Tap water that tastes bitter is most often attributed to elevated levels of copper. Copper usually enters drinking water supplies as a result of corroded copper pipes, fittings or fixtures. Copper can begin to alter water’s taste at around 0.4-0.8 PPM.

Some people might find bitter-tasting water attributed to copper to be more metallic tasting, which we covered above. In any case, a high presence of metals (including copper) has a direct impact on the taste of your water.

A high amount of total dissolved solids (TDS) is also associated with bitter tasting tap water. Some of these dissolved minerals can impart an off-putting, bitter, metallic, or even salty taste—especially if they are composed mostly of sulfates.

Is Bitter Tasting Tap Water Safe to Drink?

For the most part. While copper at elevated levels (above 60 PPM) can cause health issues like stomach cramps, it is rare that copper concentrations will reach 60 PPM or more in a household setting. (Your water would also be bluish or green, and it’s highly likely you would have already noticed bluish-green staining in your sink or around your fixtures.)

Meanwhile, elevated TDS levels don’t necessarily mean your water isn’t safe to drink. It all depends on what specific dissolved solids are in your water.

What Can I Do About Tap Water that Tastes Bitter?

If you suspect your bitter tasting water is the result of copper corrosion, have your pipes and fixtures inspected.

If you’re looking to use a household pitcher filter, make sure copper is listed among the contaminants certified for removal. Otherwise, more advanced treatment systems (like reverse osmosis) are often certified to remove copper.

Likewise, TDS levels can only be reduced by filtration technologies that are certified to reduce them, like reverse osmosis and nanofiltration. Always research your treatment options to confirm they are certified to remove your target.

Why Does My Tap Water Taste Salty?

Tap water that tastes salty most likely has a high concentration of chloride ions. Not only a key part of table salt (sodium chloride), chloride is a part of common compounds like potassium chloride and calcium chloride that also impart a salty flavor to water.

Chloride is present in rainwater, streams, groundwater, seawater, wastewater, urban runoff, geologic formations, and animal waste streams. Common causes for elevated chloride levels in water supplies include:

• Snowmelt and rainfall washing road salts into local water supplies 
• Seawater entering your local water supply
• Agricultural waste or runoff entering the water supply

While chloride ions are the most likely culprit if your water tastes salty, sulfates may also be to blame. Sulfates occur naturally in certain soils and rocks, and as groundwater moves through the earth, these sulfates can make their way into the local water supply.

Is Tap Water that Tastes Salty Safe to Drink?

Depending on the source, tap water with elevated chloride levels is not harmful to your health, although those on low sodium diets will want to investigate the situation (as high sodium levels may accompany high chloride levels). On the other hand, elevated chloride levels can be bad for your pipes and may promote corrosion (especially road salt runoff that has entered private well supplies).

Elevated chloride levels from industrial waste or wastewater contamination is a more serious issue and should be investigated further. The results of a laboratory water test will help determine the proper course of action.

Sulfates are not harmful to your health, although elevated sulfate levels have been known to cause diarrhea.

What Can I Do About Tap Water that Tastes Salty?

Unfortunately, household filters that use activated carbon do not remove chloride or sulfates.

• For chlorides
  Reverse osmosis and distillation remove chlorides
  
• For sulfates
  Reverse osmosis, anion exchange, distillation, and deionization remove sulfates

Why Does My Tap Water Taste Like Plastic?

The most likely cause for tap water that tastes like plastic is the leaching of contaminants from plumbing made of PEX, PVC, or another plastic polymer material. Cheap and easy-to-install polymers have taken over the tap water plumbing market in recent years.

There are many types of plastic pipes, and all of them are stronger and more durable than the plastic in your typical water bottle. Alongside PVC, chlorinated polyvinyl chloride (CPVC), high density polyethylene (HDPE) and cross-linked polyethylene (PEX) are the main types of plastic pipes in circulation.

Is Tap Water that Tastes Like Plastic Safe to Drink?

There isn’t a straightforward answer to that question. PEX and HDPE are touted as safer than PVC and CPVC because there are fewer solvents and glues. The actual long-term safety of plastic pipes remains understudied and uncertain.

In lieu of any federal standards for plastic piping, the National Sanitation Foundation (NSF)’s NSF/ANSI Standard 61: Drinking Water System Components-Health Effects is the standard for testing and certifying plastic pipes. Earning certification means a product has met the NSF’s specifications, but without adequate industry-wide research, it cannot necessarily certify that there are absolutely no health risks associated with plastic piping.  

Researchers have found over 100 compounds in drinking water associated with plastic pipes. The health impacts of plastic on tap water quality is highly dependent on which water treatment (chlorine vs. chloramine) is used and how the treatment impacts each pipe material.

What Can I Do About Tap Water that Tastes Like Plastic?

To really pinpoint the appropriate treatment method, you would have to know what compounds are making your water taste like plastic. If you are detecting a plastic flavor, it is likely that there are plastic leachates in your water. It’s highly recommended you test your water for the presence of plastic leachates. Lab tests help you better understand the potential for health impacts and how to best treat your water supply.

The first line of defense in reducing a plastic taste in your water is flushing out your pipes as per manufacturers’ recommendation (especially for a new plastic pipe install). If that doesn’t solve the problem, activated carbon is an effective way to treat many taste issues caused by VOCs, potentially including the taste of plastic.

Reverse osmosis is another potentially effective option depending on the source of the taste. You can also have your pipes inspected if you suspect your plastic piping is old.

Why Does My Tap Water Taste Dirty, Moldy or Musty?

Tap water that tastes moldy, musty, or even dirty is usually due to the presence of algal blooms, sediment, or the growth of harmless, naturally-occurring bacteria.

Algal Blooms

Most common in the spring and summer time, algal blooms are the rapid growth or accumulation of microscopic algae and cyanobacteria (which produce cyanotoxins, some which can be very toxic) in freshwater or saltwater sources. Algal blooms discolor the water and form a surface scum in the process. Some algae produce chemicals that cause water to taste moldy or musty.

Municipal water systems are treated with disinfectant, which eliminates any algae or bacteria before it gets to your tap, but a moldy or musty flavor may linger.

• Do Algal Blooms Affect Well Water?
  Wells that are within approximately 100 feet of a water source experiencing an algal bloom can be affected. Algal blooms can also cause water to appear green or murky.[4]

Bacterial Growth

Bacterial growth in your water system can also cause a moldy or musty flavor to develop. Most commonly, these are harmless iron-related bacteria that feed on trace levels of iron in water. Because municipal water is treated and monitored, iron bacteria growth is largely an issue for private well owners.

Sediment

Also largely a problem for private well owners, actual dirt or sediment can get into your supply if you have issues with your catchment or well casing. If you notice sediment (your water will be murky or have particles floating in it) you might want to inspect your well setup.

Is Tap Water that Tastes Dirty, Moldy, or Musty Safe to Drink?

Those on public water supplies will want to reach out to their utility as contaminants that make water taste dirty, moldy, or musty should not appear in municipal water. While unpleasant, most of the contaminants responsible for water that taste moldy or musty do not cause serious illness. 

It’s recommended to treat the source of the problem as soon as possible. Furthermore, we recommend private well owners near an algal bloom event (within 100 feet) to avoid drinking their water.

What Can I Do About Tap Water that Tastes Dirty, Moldy, or Musty?

• Public Water Supplies
  If your tap water comes from a public utility, you should reach out and see if there’s been an algal bloom event that impacted a nearby reservoir or water source.
  
  Sediment or iron bacteria should not be issues for those on city water and should be reported right away if noticed.
  

• Private Well Owners
  The source of moldy, musty, or dirty-tasting water should always be remedied in place of band-aid filtration or treatment.
• In the event of an algal bloom, it is recommended to have your water tested for cyanotoxins, and to have your well casing inspected. Algal blooms are temporary occurrences. Shock chlorination can help.
• If you suspect your water has iron bacteria, consider shock chlorinating your well system and testing your water’s iron levels.
• If sediment is getting into your well water, have your well system inspected and repaired.

Why Does My Tap Water Taste Sweet?

The flavor of your tap water can take on a sweetness when it’s rich in certain minerals (like calcium and magnesium). Some people have associated water that is higher in alkalinity with a sweeter flavor.

Is It Safe to Drink Tap Water that Tastes Sweet?

Water with a slightly sweet flavor from mineral content is not a cause for concern.

What Can I Do About Tap Water that Tastes Sweet?

If a somewhat sweeter, more mineral rich glass of water isn’t your thing, there are filtration options that can help reduce the mineral content in your water.

• Filtration
  Reverse osmosis systems filter most minerals from your water; activated carbon filters (from pitcher filters to more complex whole-home filters) are commonly used to treat taste issues, but they won’t remove calcium, magnesium or alkalinity; water softeners are used to help treat water hardness and high alkalinity levels.
• Flushing
  You can also flush your water system out by running the tap at full for upwards of 5 minutes to use the pressure to help clear your pipes out.

It’s worth noting, however, that your drinking water should contain minerals in order to maintain a healthy, balanced diet.

Why Does My Water Taste Like Rotten Eggs?

Water that tastes (and smells) like rotten eggs is likely the product of sulfur-reducing bacteria which can grow in your drain, your water heater, or your well. These bacteria use sulfur as an energy source, chemically changing natural sulfates in water into hydrogen sulfide (H₂S), which emits that distinct, rotten egg odor. 

What Is Hydrogen Sulfide?

Hydrogen sulfide (H₂S) is a colorless, flammable gas most known for its trademark rotten egg odor. H₂S can form naturally underground as organic matter decomposes, but is most often produced by sulfate-reducing bacteria that convert sulfates in water into hydrogen sulfide.

Sulfate-reducing bacteria live in oxygen-deficient environments (like landfills and deep wells) and can form in water treatment devices (like water softeners and water heaters). H₂S most commonly affects well owners. Warmer temperatures bring hydrogen sulfide odors out more intensely.

Is It Safe to Drink Tap Water that Tastes Like Rotten Eggs?

While unpleasant, sulfur (“rotten egg”) taste and smell is generally not a health concern at levels typically found in tap water.

It is worth mentioning that, apart from the unpleasantness of the odor, hydrogen sulfide left unmanaged in a well supply can be corrosive to iron, steel, stainless steel, copper, and brass, leading to greater unwanted problems with your plumbing—including the possible leaching of other harmful chemicals.

What Can I Do About Tap Water that Tastes Like Rotten Eggs?

You can remove the taste of rotten eggs from your tap water via:

• Shock chlorination
• Activated carbon filtration (which include common pitcher filters)

When Should I Be Worried About Tap Water that Tastes Bad?

While the majority of mild cases of funny or unusual tasting water are nothing more than an annoyance, there are a few cases that are cause for concern.

Public Water Supplies

If you source your water from a municipal or public utility, your tap water is carefully monitored and treated. It’s a good idea to reach out to your utility anytime your tap water experiences a sudden change in taste, color, or smell. You should investigate matters further with your utility if your tap water:

• Tastes more intensely of chlorine than usual for more than a few days
• Tastes moldy or musty for more than a few days

Private Well Owners

As a private well owner, your water quality is your responsibility. It’s recommended that you test your well water at least annually, and after any significant events that may have impacted the environment nearby (like natural disasters or industrial accidents).

Because nobody else is monitoring your well setup, variations to taste, color, and smell are important signs you should inspect your system. These are some warning signs that something may be going wrong:

• Tap water that is suddenly saltier than usual could be a sign that your well has been compromised by runoff
• Tap water that tastes moldy, musty, or dirty is a sign that your well has been impacted by an algal bloom or some disturbance and needs disinfection
• Tap water that tastes or smells like rotten eggs is also a sign that your well setup could use another round of disinfection

When Should I Test Tap Water that Tastes Bad?

Testing your water is never a bad idea, especially when your tap water has undergone a sudden aesthetic change (like changes in taste). While there might not be direct health impacts for some of the items we covered above, there may be risks of damage to your plumbing, which can cause costly problems—and health complications—down the line.

What’s the Takeaway?

Aesthetic issues (taste, smell, color) with tap water are leading reasons people opt for more expensive—and environmentally harmful—options for their daily hydration. Understanding why your water may appear unpalatable is the first step to knowing what you can do to go back to trusting your tap water.

• The flavor of your tap water is not often a cause for alarm, although well owners should pay close attention to aesthetic changes in water quality.
• There are a variety of treatment options available to help improve the flavor of your tap water, but it’s vital to know the cause behind the changes before opting for treatment. 
• Even if what’s causing funny or off-tasting water is not harmful to your health, it may be harmful to your plumbing and is worth investigating to save you time and money in the future.