How to Remove Nitrates from Well Water: 2021 Ultimate Guide

How to Remove Nitrates from Well Water

If you own a private well and you live in a rural area, there’s a good chance that your water contains traces of nitrates. Nitrates are a common contaminant and are tasteless, colorless and odorless, but can cause health problems in humans and animals that consume them in excess.

It’s recommended that you get your well water tested regularly, preferably once a year, to check for nitrates in drinking water and respond as needed. There’s no need to drink water that’s laced with nitrates nowadays, and you really shouldn’t, for the sake of your own health. In this guide, I’ll be discussing the importance of clean, nitrate-free water and sharing the most effective methods for removing water nitrates.

💡 What Are Nitrates?

Nitrates are a type of inorganic compound that often occur naturally in the environment, including the soil, the atmosphere, and water. They may also occur synthetically as a result of human activity.

Because nitrates are highly water-soluble, they can almost fully dissolve in water. They’re produced when plants decompose, and can also be found in animal waste. Nitrates in water may be produced from agricultural processes. There are several ways that nitrates can get into groundwater: flooding, soil erosion, and, most commonly, rainwater and snow. If you have a shallow well, you’re more at risk of a small amount of nitrate entering your water.

Nitrates are made from one part nitrogen and three parts oxygen. The reason why nitrates are often associated with farming activity is because nitrogen is essential for crop growth, as it’s needed by chlorophyll, which stimulates photosynthesis – a process that all plants must carry out to survive. Because of this, nitrates are typically used in fertilizers, which are sprayed on plants to encourage them to grow. When it rains or floods, these fertilizers may be transported into bodies of water, increasing groundwater nitrate levels. They may ultimately pass into wells through aquifers.

Every living creature needs nitrogen for healthy growth, but consuming excess nitrates can be dangerous.

nitrates from agriculture fertilizers

🩺 Health Risks Associated with Nitrates

Consumption of water that’s contaminated with nitrate may make humans more susceptible to public health risks, especially in babies, children, infants, and pregnant women. Concentrated, high levels of nitrate may affect the red blood cells in infants, preventing them from being able to adequately transport oxygen to the different parts of the body.

Infants whose red blood cells underperform because of nitrogen may experience a condition known as methemoglobinemia (or “blue baby syndrome”). In this condition, the hemoglobin in infant blood cells may be converted to methemoglobin, which, unlike hemoglobin, can’t carry oxygen. Adults are more protected because their bodies have enzymes that prevent this from happening, but babies and the elderly don’t have this defense mechanism against methemoglobin.

Methemoglobinemia is known as “blue baby syndrome” because infants with the condition have blue nail beds, and a blue nose, mouth and lips. This is usually accompanied by a fever, diarrhea, and vomiting. Pregnant women should avoid drinking untreated water with excessive nitrate as the nitrogen might pass on to their infants. Baby formula that contains high-nitrate water also poses a serious concern.

Adult men and women are generally less at risk of methemoglobinemia, but that doesn’t mean it’s safe for them to drink tap water carrying larger levels of nitrate and nitrite. Nitrates in water may be linked to a number of health conditions, making adults more susceptible to nausea and headache, rapid heartbeat and gastrointestinal disorders.

Research by the World Health Organization (WHO) suggests that nitrate is likely carcinogenic in adults and children, though it’s thought that only excessive nitrate levels have the potential to cause increased risk of cancer. Ultimately, more research needs to be carried out before scientists can properly understand the dangers of drinking trace levels of nitrates in tap water.

🤔 How Do Nitrates Get Into Drinking Water?

Nitrates and nitrites typically enter into water supplies through industrial and agricultural (farm) runoff. They may also enter water through damaged disposal or septic tanks or a sewage plant. Rainwater is the biggest cause of nitrates and other organic and inorganic minerals in drinking water; it carries manure from farm livestock containing nitrates, and fertilizers from crops, into lakes and streams and down through the earth. Here, nitrates present in groundwater can enter wells through aquifers.

It’s unlikely that you’ll find dangerous levels of nitrates within city drinking water supplies. They’re a much more common problem in wells, especially in rural areas with high levels of agricultural activity and high use of fertilizers. Farming processes, such as the use of fertilizer and septic systems and rearing livestock, are two key causes of nitrate in drinking water. Many people in rural communities don’t have access to city water, which makes it even more important that the water from their wells isn’t contaminated with more than the maximum contaminant level of nitrogen, and, if so, this impurity is removed.

Additionally, industrial activity may feed nitrogen into groundwater. In several industrial processes, such as ceramics production and food processing, nitrates are used as oxidizing agents.

nitrate in groundwater

What is a Safe Level of Nitrates in Drinking Water?

The Environmental Protection Agency (EPA) sets out Maximum Contaminant Levels (MCLS) for a number of common drinking water contaminants that could affect health when consumed in excess. As per the EPA’s recommendations, your well water should contain no more than 10 milligrams per liter (mg/L) of nitrates. If your water contains less than this amount of nitrates, you’re fine to drink it, as it’s considered “safe”.

10 milligrams per liter may also be measured as 10 parts per million (PPM). 1 PPM is equal to 1 mg/L, so whichever reading you get can easily be converted into the other.

How Can I Prevent Nitrates Getting Into My Well Water?

There are several ways that you can protect the area around your water source from nitrates, but if you’ve already built a well, it may be a case of building an entirely new well or looking at the systems you can use to control or remove nitrates, rather than trying to prevent it from contaminating your water in the first place.

If you have an old well, make sure the casings are watertight and aren’t damaged in any way, as this could make it especially easy for nitrates to feed into your water.

If you are building a new well, make sure it isn’t shallow, and, if possible, don’t install it in a sand aquifer. Both of these factors can make a well more vulnerable to nitrate contamination.

Other ways to avoid nitrate contamination are to construct your well nowhere near irrigation applications, septic systems and animal waste, inspect your well regularly for damage, and test once a year for nitrates within drinking water.

🧪 How to Test for Nitrate in Well Water

There are two ways to test for well water nitrates: private laboratory testing and DIY testing kits.

If you want to have a proper understanding of your water quality, private laboratory testing is the best solution for you. A laboratory test can indicate not only whether your drinking water contains nitrates, but also exactly how much. If your water supply contains more than 10 mg/ L of nitrates, you’ll need to think about nitrate control and removal pretty quickly. But even if your water does include less than the maximum nitrate contamination that’s considered safe, you might still want to see that nitrate in your water supply is removed.

In between your laboratory tests, you can also periodically test for concentrations of nitrates in drinking water sources yourself, to check for any unnatural increase in the contaminant. You can buy test kits online that can be dipped into a stagnant water source to determine whether it contains specific contaminants. In a test that detects nitrate, a high nitrate level will cause the testing strip to change color. If the color indicates that you have too much nitrate contamination, you should arrange for another laboratory test and switch to bottled water for the time being.

✅ How to Remove Nitrates from Water

Not all water filters can remove nitrate, so before purchasing a water treatment solution, it’s wise to do your research and know your options. The best systems for nitrate removal are highlighted below.

Ion Exchange

Ion exchange is a process that takes place inside water softeners, installed at your home’s point of use for whole-home softening benefits. Though water softeners are typically used to eliminate hard water issues, they don’t only treat calcium and magnesium ions – they can also remove nitrate.

Water softeners feature a resin bed that’s packed with sodium (salt) ions. When water flows through the tank containing these resin beads, hard water minerals are exchanged for sodium ions, producing softened, treated water. This is known as ion exchange.

Ion exchange works in the same way to remove nitrate from water, except the system uses chloride instead of sodium in the resin bed. When water flows through the tank, the resin bed releases the chloride ions and attracts the nitrate ions to its surface in a process called anion exchange.

You will need to make sure you keep an eye on the ion exchange resin bed and check that it’s regenerating frequently enough to make room for new nitrates, as the surface of the media will become too saturated with contaminants eventually, and will need to be flushed. Eventually, the ion exchange cartridge will require replacing. The worse your water quality, the quicker the media cartridge will reach the end of its lifespan.

The most effective ion exchange can only happen when you have high levels of nitrate and low levels of sulfate ions in your drinking water. That’s because this type of ion exchange typically attracts both contaminants together, favoring sulfate over nitrates, which means if you have high sulfate levels, you may not benefit from complete nitrate removal.

Reverse Osmosis

Another popular means of eliminating nitrates in water, reverse osmosis water treatment can effectively eliminate more than 99.9% of all total dissolved solids. A reverse osmosis filtration system is typically installed at a specific point of use in your home, or you might prefer to install a whole house system. Reverse osmosis systems typically consist of several filters, including a sediment filter and a carbon filter, and the highly effective semi-permeable membrane.

RO systems force water through each filter and membrane stage at a high pressure. The filters trap specific contaminants, such as sediment and chlorine, but the RO membrane is responsible for the reduction of nitrates. It has tiny pores that only allow water particles to pass through, while nitrates, nitrites and hundreds of other contaminated water culprits are unable to get any further, including bacteria, lead and chlorine. These contaminants are then flushed from the RO system with waste water.

Reverse osmosis filtration can help to greatly reduce nitrates, but it won’t eliminate them entirely. These water systems require fairly regular maintenance – you’ll usually need to change the reverse osmosis filters every six months to one year to ensure long-term adequate filtration, and the reverse osmosis membrane will need replacing every two years. Many RO systems have storage tanks to allow for access to water immediately.

You need a fairly high pressure to operate reverse osmosis systems – it’s recommended to consider buying a pressure pump if your incoming pressure is naturally quite low. RO systems cost around $200-$600, depending on the system you go for. Keep in mind that RO does produce some wastewater, so it may have a reduced efficiency compared to other methods.

reverse osmosis system example


Distillation technology uses something called a distiller. It carries out the traditional process of boiling for the removal of a whole host of problem contaminants, including nitrates in your water. In this process, water is boiled in a chamber until it evaporates, leaving behind the impurities that can’t turn into a gaseous state. Water then travels out of the boiling chamber and condenses into a liquid state in a carafe. It must pass through a carbon filter before it leaves the distillation system, which eliminates any contaminants that have been able to evaporate and condense.

Distillers are an incredibly powerful and cost-effective treatment solution. They don’t only get rid of nitrite and nitrate – they can also eliminate a high concentration of other naturally or artificially occurring impurities that can be found wells or a city water source, including illness-causing bacteria, chemicals, and heavy metals like lead. These systems reduce nitrate contaminants and are also intended for complete contaminant removal, helping to improve overall water quality.

The only real setback of a distillation system is that, because this type of treatment removes such a high concentration of contaminants from a water source, it can leave water tasting a bit “flat” or “plain”. Distillation is also a very lengthy process, taking up to 6 hours to provide a single 1-gallon batch, and up to a day to produce enough gallons for your family, so it’s not the best nitrate removal solution to consider if you’re looking for on-demand water or water for whole-house use.

water distiller

❔ Frequently Asked Questions

Does a Water Softener Remove Nitrates?

No, your typical salt-based softener systems with a brine tank can’t provide nitrate or nitrite removal. This technology might reduce concentrations of nitrate ions, but only systems that have a special chloride resin bed can be used to eliminate nitrates at present.

Does boiling water remove nitrates? 

No. Boiling water actually increases the concentration of nitrates present in a water source, so you can’t use it for removing this impurity. That’s because when you boil water, some of it evaporates, so you’re left with the same concentration of contaminants in a smaller amount of water. This means the nitrate levels actually “increase” slightly.

I have more than 10 PPM of nitrate in drinking water. What should I do?

For the time being, stop drinking your water and switch to bottled water for cooking and drinking, especially for use with baby formula. If you can, try to find out how high concentrations of nitrates have found their way into your groundwater. Is there human commercial or industrial activity such as food processing in nearby areas that could be responsible? How about manure, sewage, wastewater or improper disposal of animal waste? You might be located near to farming fields, and rain or irrigation may be sending nitrates and other inorganic chemical pesticides and herbicides across the fields towards your home. Some areas around the United States may also have higher levels of natural, organic nitrate deposits in the soil than others.

No matter why the water in your home might contain nitrates, it’s important that you get your water treated as quickly as possible with a method that effectively reduces the contaminant and improves water quality. Once you begin to treat your water with a nitrate removal solution, test it again to ensure that your nitrate problems have been resolved. If you need more help, contact your local authority for support.