Is There Chlorine in Tap Water?

Cities and municipalities have chlorinated the public water supply for more than 100 years. This well-researched water treatment solution is an important disinfection tool, but in some cases, it can also cause a distinct chlorine smell or taste from your tap.

In general, most tap water that comes from a city supply contains chlorine. However, the amount depends on various factors, including what the water utilities are treating, your home’s distance from the treatment plant and more.

While chlorination is intended to make tap water safe to drink, you may want to treat the chlorine odors and flavors. Here’s what to know and how water filtration can help.

Why Is Chlorine in Tap Water?

Water chlorination is a solution for preventing waterborne diseases and ensuring water meets the applicable safety standards. As a disinfectant, chlorine kills the bacteria and viruses responsible for these diseases. Chlorination of water was initially developed to address typhoid fever and dysentery, which were common causes of death in the late 1800s and early 1900s.

For example, one of the earliest chlorination efforts was in 1897, when a bleach solution was used after a typhoid outbreak in the U.K. The first continuous application was likely in Belgium in 1902, and countries like the U.S. and U.K. followed over the next several years. Today, most public water systems are chlorinated — and according to the Minnesota Department of Health, chlorination is the most common type of drinking water disinfection.

However, chlorination is not ubiquitous. Private well water isn’t treated by a city water department or utility, so any introduction of chlorine would be added as part of a water treatment system initiated by the homeowner. Single-serve bottled water is also less likely to contain chlorine than municipal water because bottlers typically use ozonation rather than chlorine disinfection.

What Is Chlorine?

Chlorine is a common element naturally found as a gas. Public water systems often use its processed liquid form to kill germs responsible for diseases such as hepatitis and salmonella. They may also use chloramines, which are chemical compounds containing both chlorine and ammonia.

What Are Disinfection Byproducts?

According to the Minnesota Department of Health, disinfection byproducts (DBPs) are chemicals that form when chlorine reacts with organic materials in water. This is more common when surface water is the primary source of the public water supply. That’s because surface water sources such as rivers and lakes are more likely to contain the organic materials that create the interaction.

According to the Environmental Protection Agency (EPA), there are multiple potential health effects from long-term exposure to DBPs. These include nervous system effects, liver and kidney problems, anemia and an increased cancer risk. To balance these potential risks with the many benefits of chlorinated water, the EPA has set Maximum Contaminant Levels (MCLs), which are enforceable limits on the DBP levels allowed in public drinking water. These limits help ensure that DBPs are not at levels that should cause a significant health concern. Cities must test their water against the limits, take action when necessary and notify the public.

How Much Chlorine Is in Tap Water?

Many factors influence the amount of chlorine present in drinking water. The first is applicable regulations.

The EPA has established guidelines for safe levels of chloramine and chlorine in drinking water, setting both at an enforceable limit of 4.0 milligrams per liter (mg/L). The World Health Organization (WHO) guideline for chlorine is slightly higher at 5.0 mg\L. However, the Guidelines for Canadian Drinking Water Quality state that no limitations are required for either chlorine or chloramine concentrations.

Other factors influencing the chlorine level in your water supply are related to the water treatment process. For example, chlorine concentrations may be higher the closer you live to the city’s treatment plant. It’s also important to consider the levels of bacteria or other issues originally present in the water; these also can change seasonally and can impact chlorine levels. Locations and/or times of year that see more water quality issues can require greater amounts to be used for disinfection.

Signs of High Chlorine Levels in Tap Water

Because limits are in place for chlorine’s presence in municipal drinking water supplies, the main reasons homeowners may choose to address high chlorine levels are generally related to the taste and odor of your drinking water supply rather than health concerns.

It’s important to note that there are some possible health effects in certain contexts. According to the EPA, long-term exposure to high levels of chlorine can potentially cause eye and nose irritation or stomach discomfort. Chloramines have the same effects, with the addition of anemia.

However, these are not the most common signs of high chlorine levels in tap water, nor are they the easiest to diagnose. For many people, it’s easier to consider odor and taste.

As the WHO explains, some people can taste or smell chlorine in their water at concentrations between 0.3 and 5 mg/L. There’s more variation among chloramines, with certain types identifiable at concentrations as low as 0.02 mg/L.

Address water quality problems with our Water Solutions Finder.

Note that these numbers are mostly below both the EPA and WHO guidelines. This means that you may pick up on chlorine taste or “pool water” odor even when the chemical levels are meeting every drinking water regulation. For many people, these are the main reasons to consider removing chlorine from tap water.

Can You Safely Reduce Chlorine Levels?

Cities purposefully add chlorine to the water supply to prevent waterborne disease outbreaks. Is it safe to reduce the chlorine or chloramine levels in your water if these chemicals play an important role in public health?

Initial disinfection occurs at the treatment plant. As the water travels to your tap, the chlorine remains effective and continues killing germs. This means that the chemicals have already disinfected the water supply and are generally safe to remove at home.

Testing and Treating Chlorine in Your Water

While you can often identify chlorinated tap water, it’s difficult to measure the specific amount of disinfectant present. DIY tests are available, but they can be difficult to use or interpret. That’s why it’s important to have an expert perform a professional water test to provide details on the exact chlorine concentration in your water supply.

A Culligan water test is free and happens in your home in 30 minutes or less. This test can identify chlorine, iron, total dissolved solids (TDS) and more, including water hardness. Your local water expert will walk you through the results and make personalized recommendations for the next steps.

For example, if your test results indicate the presence of other contaminants, you may choose a reverse osmosis filtration system. These systems treat your drinking water; some can target more than 90 different contaminants.

Learn more about reverse osmosis filtration systems.

If chlorine levels are causing issues throughout your home, you can choose a whole house system that specifically addresses chlorine. These filtration solutions treat all the water that comes into your home, meaning you won’t taste chlorine at your kitchen tap or smell it when you’re cleaning, bathing and cooking.

Learn more about whole house filtration systems.

Learn More About Your Tap Water Quality

Drinking water chlorination is a well-researched, long-utilized solution for preventing waterborne disease. While it can have mild health effects after long-term exposure to high concentrations, chlorine is not typically a health concern in the water supply at regulated levels.

To treat odors and tastes, you can choose between drinking water and whole home filtration systems. However, you won’t know which system is best until you learn more about your tap water quality.

Get started today by scheduling your free, in-home water test and consultation.

*Contaminants may not be present in your water.