Chlorine is one of the most widely used disinfectants in public drinking water systems worldwide. For more than a century, it has played a major role in reducing waterborne diseases by helping control bacteria and other microorganisms during water treatment and distribution.
While chlorine has significant public health benefits, many homeowners dislike its taste and odor or want to reduce the amount remaining in their drinking water at the point of use.
This guide explains why chlorine is added to drinking water, how it works, potential concerns, and practical ways to improve its taste and quality.
Looking for a countertop gravity-fed filtration system? The Big Berkey® Water Filter is our most popular stainless steel system for everyday household use.
What Is Chlorine?
Chlorine is a chemical element that has been used for water treatment since the early 1900s. Water utilities add carefully controlled amounts of chlorine to help disinfect public drinking water before it reaches homes and businesses.
Without disinfection, harmful microorganisms could multiply within water distribution systems. Chlorination remains one of the most important public health advances in modern water treatment.
Why Is Chlorine Added to Drinking Water?
Public water systems disinfect water before it enters the distribution system. Chlorine continues to work as water travels through miles of underground pipes, helping maintain water quality until it reaches customers.
Chlorine helps:
- Reduce bacteria and other microorganisms during water treatment
- Provide a disinfectant residual throughout the distribution system
- Protect water quality as it travels through pipelines
- Support public health by reducing waterborne disease risks
Because chlorine gradually dissipates over time, utilities carefully monitor chlorine levels to ensure an appropriate disinfectant residual remains throughout the distribution system.
How Much Chlorine Is Allowed in Drinking Water?
The U.S. Environmental Protection Agency regulates the use of chlorine for drinking water disinfection.
The EPA has established a Maximum Residual Disinfectant Level (MRDL) of 4.0 milligrams per liter (mg/L), or 4 parts per million (ppm), for chlorine in public drinking water systems.
Water utilities routinely monitor chlorine levels to remain within federal requirements.
Can You Taste or Smell Chlorine?
Yes.
Many people can detect chlorine by its familiar "swimming pool" smell or slight chemical taste, even when chlorine levels are well below federal limits.
The strength of chlorine taste and odor depends on several factors, including:
- The amount of chlorine added
- Water temperature
- How recently the water was treated
- Distance from the treatment plant
- Individual sensitivity
Taste and odor concerns are among the most common reasons homeowners consider point-of-use water filtration.
Potential Health Considerations
When used within EPA regulatory limits, chlorine is considered an effective and important drinking water disinfectant. However, some people prefer to reduce chlorine in their drinking water because of its taste and odor.
Another consideration is that chlorine can react with naturally occurring organic matter in water to form substances known as disinfection byproducts, including trihalomethanes (TTHMs) and haloacetic acids (HAA5).
Public water systems monitor these compounds to comply with EPA drinking water standards.
Chlorine vs. Chloramine
Although both are disinfectants, chlorine and chloramine are different chemicals.
| Chlorine | Chloramine |
|---|---|
| Acts quickly | Lasts longer in distribution systems |
| More noticeable taste and odor | Often milder taste and odor |
| Used by many utilities | Increasingly used by larger utilities |
If your water utility uses chloramine instead of chlorine, see our Chloramine in Drinking Water Guide.
How Can Homeowners Reduce Chlorine?
If you prefer to reduce chlorine in your drinking water, consider these practical options:
- Review your local Consumer Confidence Report (CCR).
- Determine whether your utility uses chlorine or chloramine.
- Allow water to stand briefly if appropriate, as chlorine naturally dissipates over time.
- Use a quality point-of-use filtration system designed to reduce chlorine.
- Replace filter elements according to product guidance.
Berkey® Water Filters and Chlorine Reduction
Berkey® countertop gravity-fed water filter systems are designed for everyday household use.
When equipped with Black Berkey® Replacement Filters, Berkey® systems are designed to reduce chlorine and a broad range of other unwanted contaminants.
Many customers also notice improved taste and odor after filtering chlorinated tap water.
For most households, the Big Berkey® Water Filter offers an excellent balance of capacity, convenience, and daily performance.
Choosing the Right Berkey® System
| System | Capacity | Best For | Product |
|---|---|---|---|
| Travel Berkey® | 1.5 Gallons | Singles & Couples | View Product |
| Big Berkey® | 2.25 Gallons | Most Families | View Product |
| Royal Berkey® | 3.25 Gallons | Larger Families | View Product |
| Imperial Berkey® | 4.5 Gallons | High Daily Water Use | View Product |
| Crown Berkey® | 6 Gallons | Large Homes & Offices | View Product |
Related Drinking Water Guides
- Drinking Water Contaminants Reference Guide
- Lead in Drinking Water Guide
- PFAS in Drinking Water Guide
- Arsenic in Drinking Water Guide
- VOCs in Drinking Water Guide
- Chromium-6 in Drinking Water Guide
- Hard Water Guide
Frequently Asked Questions
Why is chlorine added to drinking water?
Chlorine is added to disinfect drinking water and help maintain water quality as it travels through public water distribution systems.
Is chlorine in drinking water safe?
Public water systems regulate chlorine levels under EPA standards. Water utilities routinely monitor disinfectant levels to remain within federal requirements.
Why does my tap water smell like chlorine?
The familiar chlorine smell is usually the residual disinfectant left after water treatment. Some people are more sensitive to the taste and odor of chlorine than others.
Can boiling remove chlorine?
Chlorine naturally dissipates over time, and boiling may accelerate this process. However, boiling is generally not the most practical method for improving the quality of everyday drinking water.
What is the difference between chlorine and chloramine?
Both are drinking water disinfectants. Chloramine lasts longer in water distribution systems, while chlorine works more quickly and often has a stronger taste and odor.
Which Berkey® system is best for most families?
The Big Berkey® Water Filter is our most popular system because it offers an excellent balance of capacity and countertop convenience.
Where can I buy replacement filters?
You can shop genuine replacement elements on our Berkey® Replacement Filters page.
Final Thoughts
Chlorine has played an essential role in protecting public health through drinking water disinfection for more than a century. While many homeowners appreciate the protection it provides, others choose to reduce chlorine to improve the taste and odor of their everyday drinking water.
For households looking for a convenient countertop gravity-fed filtration system, the Big Berkey® Water Filter remains our most popular choice for daily use.