Common Contaminants in Well Water and How to Remove Them

Common Contaminants in Well Water and How to Remove Them

Posted by Kenton Jones on May 1st 2024

Over 15 million households in America depend upon water from private wells for drinking, cleaning, bathing, and cooking. While people who live in cities or have their water supplied by the municipality know that their water is subject to strict environmental guidelines, the same is not true of private wells. So it is dependent upon the owners of these wells to make sure that their water is safe.

Ensuring that your drinking water is contaminant-free is essential for your family's health. Regular testing of your well water and the use of an appropriate filter are two of the most important things you can do to verify that your family is getting the best possible water from your well.

Contents In This Post:

Causes and Signs of Contaminated Well Water

Key Contaminants in Well Water

How Often Should I Test My Wells?

When and Why To Test Your Well Water

How To Remove Contaminants From Well Water

How To Choose The Right Filtration System For Your Well Water

Look To Multipure For A Drinking Water Filtration System

Causes and Signs of Contaminated Well Water 

Both environmental factors and human activities can result in well water pollution:

  • Microorganism runoff: Water runoff from rainfall or melted snow can enter private wells, washing microorganisms into the well system or seeping into it from underground.
  • Leakage from storage tanks: Underground storage tanks and septic leach fields can leak waste into water wells, introducing microorganisms into drinking water.
  • Fertilizer runoff: Nitrate is a common contaminant present in chemical fertilizers, human sewage, and animal waste. It may enter private wells through groundwater movement, runoff or seepage.
  • Household plumbing: Heavy metals can leach into drinking water from a home's plumbing and service lines.
  • Household products: Organic chemicals in household products like inks, paints, dyes, and disinfectants can also seep into private wells through waste disposal spills and surface water runoff.

Signs of contaminated well water include:

  • Visible sediment in water
  • Murky or cloud water, indicating the presence of dirt, silt, or rust
  • Oily film on water, indicating the presence of excess organic substances
  • Brown, green, or red stains on sinks, clothes, and appliances
  • Rotten egg, detergent, or chlorine smell
  • Salty, soapy, metallic, or chemical taste

Key Contaminants in Well Water

Common contaminants found in well water, according to the Centers for Disease Control (CDC), include:


While the word arsenic conjures up images of poisoning victims in detective novels, arsenic is another naturally occurring substance. But when arsenic is in your well water, it can be a serious problem.

Arsenic often seeps into well water from agricultural and industrial pollution, including fertilizer runoff, or from natural deposits in the earth. Drinking water with arsenic in it can lead to serious health problems, including cancer, heart problems, and neurological issues. Not every well contains arsenic, but it's important to test your well to see if it is present.

Volatile Organic Compounds (VOCs)

This contaminant refers to industrial chemicals that easily change state through evaporation and are particularly harmful to humans. The VOCs found most often in American wells, according to the United States Geological Survey (USGS), are chloroform, alachlor, atrazine, and benzene.

The location of your home is a key factor in whether you need to worry about VOC contamination in your well water. If you live close to a gas station or manufacturing plant, you need to be particularly vigilant about your well water. MTBE can be found in gasoline, but due to environmental health concerns, its use has declined since 2005. It's important to check for VOCs regularly, particularly if you live close to the structures mentioned above.

Synthetic Organic Contaminants (SOCs)

Unlike VOCs, which derive from naturally occurring hydrocarbons like petroleum, SOCs are entirely human-made. Examples include chlordane and methoxychlor, both pesticides or compounds used in pesticides, as well as synthetic benzene, a chemical used in industrial processes to make resins, plastics, and dyes. They may make their way into groundwater and well water through agricultural and industrial runoff.

Adverse health outcomes associated with ingesting SOCs from well water include elevated cancer risks, damage to the nervous system and kidneys, and developmental delays in children.

Microbial Contamination

While some microbes found in water can be harmless, some bacteria can be extremely harmful to humans. E. coli, crypto, and giardia are three of these more harmful kinds of microbes. They usually are found more often in surface waters like rivers or lakes. But they make their way into wells when there are heavy rainfalls or floods or if you do not properly maintain your well. Once bacteria and other microbes make their way into your well, they live there for a long time, even if the water is extremely cold.

Another form of bacteria that private well owners should be concerned about is fecal chloroform bacteria. If this is found present in your well water, it could be a sign of problems with your septic system.

Additional Contaminants

Additional contaminants that can be found in well water include lead, mercury, radon, microplastics, PFAS, and bisphenol A (BPA).

Health Impacts of Well Water Contaminants

If contaminated, well water can make you sick and lead to various health problems, including gastrointestinal illnesses, neurological problems, and even reproductive issues. Well water contamination can be especially dangerous for infants, pregnant people, and older adults.

Short- and long-term contaminated well water symptoms include:

  • Infectious diseases like hepatitis
  • Chronic, long-term conditions like cancer, when exposed at low doses for long periods
  • Illnesses that cause vomiting, stomach pain, diarrhea, headache, fever, and kidney failure
  • Skin discoloration, nervous system problems, or reproductive effects from chemical exposure

The specific health impacts of drinking contaminated water will depend on the type and amount of contaminant consumed, its concentration in the water, and individual susceptibility.

How Often Should I Test My Wells?

You should check your well every spring for cleanliness, mechanical issues, and the presence of contaminants. More than a few problems with contaminants are caused by poorly maintained systems or ones that have grown old and whose components are failing. You should also test your well in the following circumstances:

  • There are reports of other problems with other wells in your area.
  • There has been extremely heavy rainfall, a flood or some other disturbance to the land in your area, such as new construction.
  • You live near a waste disposal site.
  • You discover you have had problems with your septic system. If it is anywhere near your well, it's a good idea to check to see if any fecal material has seeped into the well.
  • Any part of your well system has been repaired or replaced.
  • If you work with chemicals on your property, keep the water hose outside of any mixing container. If you place it inside the container, it may be possible that chemicals can be siphoned into a household water system.
  • Make sure that the cover or cap for the well is intact. Remember, the top of your well should be at least a foot above ground level.
  • Most wells last about 20 years. When your well has reached the end of its serviceable life, make sure you contact a certified well driller and pump installer to properly close the existing well and drill a new one.

Your state's, your municipality's or your county's environmental or health departments will often do tests for a series of contaminants. These departments will also have a list of licensed laboratories that can test your well water for a variety of contaminants.

The United States Environmental Protection Agency (EPA) also maintains a database of certified laboratories that can test for well water contaminants.

It's also a good idea to get your well tested if you are in the process of selling your home and land. If the buyer later discovers that the well is contaminated or not properly maintained, it could put the sale in jeopardy. Many states require testing before the sale of a property with a private well can go forward.

When and Why to Test Your Well Water

The CDC recommends that you test your well water at least once a year. This includes testing the water both from your tap and from the source. If you have a shallow well, you should probably test your water seasonally, especially if you live in an area with heavy rainfall, floods, or a great deal of agricultural activity. Your local health department can help you test your drinking water. Also, there are many self-testing kits now available either in retail outlets or online.

Testing your water allows you to deal with any problems that may exist in your water supply. Whether your well water is to be used by humans, by livestock or for watering plants, testing yearly or more frequently will help you make the right decisions about your well water and how to fix it if there are any problems.

It is important to regularly test your well water because:

  • It helps you identify any problems.
  • It is the best way to ensure that humans and animals can use your water.
  • It allows you to see how your water supply has changed over time. Are there more contaminants than there used to be? Are there fewer? What could be the reasons for either situation?
  • It shows you how effective your current water treatment regimen is.
  • If you sell your house and property, being able to show a potential buyer the records of your yearly well testing to assure them that the well is in good shape will greatly assist the sale of your property. On the other hand, if you're buying a property that includes a private well, you will want to see the yearly records of water tests. If the current owner has not done regular tests of the water quality, make sure you carry one out before you sign the final contract.

When testing your well water, you need to check for several important factors:

  • Basic potability: This is to check if your water meets minimum levels. This test will look for nitrates, sodium, chloride, iron, total dissolved solids, how hard your water is, and its pH levels.
  • Coliform bacteria: This test looks for microorganisms that can be potentially harmful to humans.
  • Arsenic: As mentioned above, arsenic can seep into well water from industrial and agricultural pollution and, if consumed, can lead to health problems.
  • Other ions: You look for ions not necessarily because they're bad for your health but because they are bad for your water. Chloride, sulfate, magnesium, and other ions make your water taste bad and smell bad.
  • Sulfate: If there is too much sulfate in your water, you will have digestive problems, gastrointestinal discomfort, and diarrhea.
  • Dissolved solids: This checks for the total amount of inorganic substances that can be found in your well water. If you find that you don't enjoy drinking your well water, it could be because there's a high level of dissolved solids.

How to Remove Contaminants From Well Water

Water filtration systems can help treat well water and reduce contaminants in your drinking water. Many can also improve the taste and smell of the water, providing a better drinking experience. You'll find two types of filtration systems to treat well water — point-of-use or whole-house filtration systems.

  • Point-of-use systems: These filtration systems treat water on demand while delivering water to a tap, such as your kitchen or bathroom sink. The Multipure Aquaperform is a point-of-use carbon block water filter system you can install under your sink or on your countertop.
  • Whole-house filtration: These systems are often installed near the water meter and treat most of the water entering a home, including water used to run your dishwasher, shower, or laundry. The Multipure Aquasource is a whole-house system that you connect at the water entry point, reducing particulate matter while delivering cleaner, chlorine- or chloramine-free water to every faucet in your home.

Most household water treatment systems consist of a filtration system that removes impurities through a physical barrier, chemical or biological process.

>How to Choose the Right Filtration System for Your Well Water

It's always a good idea to test your well water so you know if you have any problems. But another excellent way to protect your family is to use a filter. The best type of filter is a drinking water system like the kind you can find from Multipure:

  • Reduces common contaminants:The Multipure Aquaperform is a point-of-use system that provides filtration of the water coming from your kitchen faucet, so your family will enjoy drinking water free from many aesthetic and health-related contaminants. The Aquaperform is certified to reduce arsenic, PFAS and microplastics, protecting your family's health.
  • Provides good water pressure: Anyone who has used a water filter on a kitchen sink knows that one of the most significant problems is a loss of pressure. But Multipure's system of innovative technology and design means you'll still have the water pressure you want, along with the filtration that you need.
  • Uses carbon block water filters: Multipure'scarbon block water filter will also allow you to treat contaminants like bacteria & virus (Aqualuxe only), arsenic, asbestos, lead, mercury, and chloramine. Chloramine can also damage your home's plumbing and, in some cases, lead to additional microbial growth. Chloramine is also toxic to fish and any water-based reptiles.
  • Easy to maintain: Just one filter change each year provides you and your family with the best quality drinking water available for just pennies a gallon.

Look to Multipure for a Drinking Water Filtration System

Certified performance matters. At Multipure, we pride ourselves on providing home drinking water systems that reduce common contaminants to keep your household safe. Check out Multipure's NSF certifications to learn more about the rigorous examination and testing all our products undergo, or peruse the complete list of contaminants the Aquaperform can address.

Multipure has been in business since 1970 to help families find clean drinking water. Our founders and our company believe that all people should have affordable access to the best drinking water — water that is clean, delicious, and free of contaminants. Water that you feel comfortable serving to your family, your pets, and your friends.

Browse our drinking water systems or contact us to learn more.