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Home » Water Education & Testing » How to Remove Nitrates from Well Water

How to Remove Nitrates from Well Water

By: Craig Smith
Last Updated:

If you get your water from a private well, you already know that you’ve got to look out for common contaminants – like iron, sulfates, manganese, and even nitrates. While having trace amounts of nitrates is pretty normal in your well water, this contaminant can pose a health risk when you consume excess amounts of it.

Fortunately, there are ways to test your water for nitrates, as well as plenty of techniques for how to remove nitrates from well water – here’s what you need to know.

Nitrates: What Are They?


When plants decompose, or animals leave waste behind, nitrates get produced. These inorganic compounds can be found almost everywhere – in water, soil, or even the atmosphere.

Certain agricultural processes tend to produce a lot of the nitrates that you’ll find in your water, although there are several other ways that nitrates may end up in groundwater (and then your well water).

As inorganic compounds, nitrates are important for growth. Every living creature, from field crops to humans, needs a certain amount of nitrates for healthy growth.

However, like many total dissolved solids (TDS), nitrates can begin to cause problems if you’re consuming more than a healthy or normal amount.

The Dangers of Excess Nitrates

drinking water

Low levels of nitrates in your well water won’t hurt you, but high and concentrated amounts can make you more susceptible to a variety of health risks. Vulnerable groups like infants, small children, or pregnant women are even more at risk for the dangers of excess nitrates in drinking water.

For infants or babies, too many nitrates can affect how the red blood cells in their bodies work and prevent them from transporting oxygen effectively. Left untreated, these underperforming blood cells in babies can lead to a condition called methemoglobinemia, or “blue baby syndrome.” Symptoms of blue baby syndrome include:

  • Blue-ish lips, nail beds, or mouth
  • Diarrhea and vomiting
  • Fever

“Blue baby syndrome,” like the name suggests, is a much bigger concern for infants younger than six months than it is for adults. Adults have enzymes in their bodies that prevent their blood cells from becoming affected, but babies haven’t developed these yet.

However, while adults themselves aren’t at high risk for the condition, pregnant women can still pass it on. When they drink contaminated water with too many nitrates, they can pass this nitrogen on to the fetus, and “blue baby syndrome” may occur.

Still, adults can also be susceptible to certain health risks when their drinking water is full of nitrates. Over time, adults may become vulnerable to certain gastrointestinal disorders, chronic nausea, rapid heartbeat, or recurring headaches. And, if you have an existing condition like anemia, lung disease, heart disease, or other metabolic problems, you have a greater risk of developing these symptoms.

There’s also research that suggests excessive levels of nitrates could be linked to an increased risk of cancer, but the link between the two is still being studied.

While studies do show that high levels of nitrates are a threat to your health, especially for infants, children, and pregnant women, scientists are still uncovering just how dangerous too much nitrates or nitrites can be.

How Do Nitrates Make it Inside Your Well Water?

tap water

As risky as high levels of nitrates can be, how do such dangerous levels of nitrates make it into your tap water?

While nearby damaged septic tanks or sewage plants could produce nitrates that end up in your water, the biggest culprit is rainwater.

In general, rainwater is responsible for both organic and inorganic compounds getting inside your drinking water – but it can also carry nitrate-heavy manure or fertilizers from farms. As a result, high levels of nitrates are a much bigger problem for private wells on farmland or in rural areas than for wells within city limits.

However, it is still possible for dangerous levels of nitrates to get in your well water even if you don’t live in the country. Certain industries, like food processing or ceramic production, use nitrates in their processes. During production, some nitrates may end up in the atmosphere or the soil and make their way back to your well. 

How to Test Your Well Water for Nitrates


Unlike some contaminants, there are no clear signs that your water supply has too much nitrate, so it’s not always easy to detect. Certain contaminants, like sulfur, may give off an odor, but nitrates are colorless, odorless, and tasteless.

Besides the serious health conditions that result from high levels of nitrates, the best way to identify nitrates in your water supply is by testing it at least once a year. There are a couple of ways you can perform testing: with a private laboratory test or an at-home DIY testing kit.

Laboratory tests tend to be more intrusive, and if there are nitrates, they can give you a better idea of just how high the levels are. If you already suspect that your water supply has too many nitrates, you may want to opt for a laboratory test.

However, if you’re just performing a routine test, DIY testing kits can provide faster results, and they’re usually more affordable as well. For DIY kits, you’ll usually dip the testing strip in a glass of water, and the color changes if you have high levels of nitrates. The only downside to a DIY testing kit is that they usually can’t tell exactly how high the levels actually are.

While you’re testing, it’s important to remember that low levels of nitrates are safe and fairly common in rural areas and private wells. But if the test shows that you have more than 10 mg/L of nitrates, your water supply isn’t safe, and you need to remove the excess nitrates.

How to Remove Nitrates from Well Water

Once you know that you need to remove nitrates from your water, the next step is finding the best water filter for well water. There are plenty of options available, but the three systems below are the most common.

Reverse Osmosis

With reverse osmosis, you’ll be using pressurized water through a membrane with tiny pores to remove the contaminants. The membrane acts as a filter, separating the nitrogen and hydrogen ions from the rest of the clean, safe water. The treated water continues to a storage tank until it’s ready to use, and the nitrates left behind get flushed down the drain.

Reverse osmosis is one of the most effective ways to filter your water. Not only can it remove up to 92% of nitrates from your supply, but this system should also eliminate up to 98% of other contaminants as well.

Reverse osmosis systems work well for many private wells – but if you have extremely high levels, you may need to go with a different removal method. For instance, if you have 30 mg/l of nitrate in your well water, an RO system should be able to bring this back down to a safe level easily.

But with an extremely severe nitrate issue (100 mg/l), an RO system wouldn’t be able to eliminate enough of your nitrates.

Ion Exchange


Another effective way to rid your water supply of excess nitrates is through ion exchange. This process happens inside water softeners, which are designed to remove water-hardening minerals like calcium and magnesium.

The exchange process works by using a resin bed full of sodium ions. Your contaminated well water has to pass through the resin bed, and once it does, the contaminants get exchanged for the sodium ions. The softer, treated sodium ions pass through, and the contaminants get left behind in the resin bed.

For lowering nitrate levels, ion exchange works the same way, but it swaps chloride for the sodium ions instead.

An ion exchange can take care of extremely high levels of nitrates, but it won’t be effective if you also have a lot of sulfates in your water. The chloride ions attract both nitrates and sulfates, but it favors the nitrates more – which means you won’t see a ton of sulfate removal.

However, if you decide to go with ion exchange, it’s important to replace the cartridge regularly. The resin bed can get full of contaminants and stop working over time.

Water Distillers

If ion exchange and reverse osmosis can’t take care of your system’s nitrates, a water distiller might. This method works by boiling your well water to remove common contaminants, including nitrates.

The distiller will boil your water until it evaporates, and the contaminants that can’t turn into a gas get left behind. From there, the new, uncontaminated water turns back into a liquid and passes through a carbon filter that takes care of any lingering contaminants.

As effective as they are, distillers are a popular option for a lot of property owners. Not only can they deal with extremely high levels of nitrates, but they’ll also take care of other harmful chemicals or bacteria that may have found their way into your water supply.

But there are a couple of downsides to a distillation system. The distillation process can take hours to complete, which makes it inconvenient if you need water for the entire house or family. If you’re relying on a distiller, you may not always have enough clean, treated water when you need it.

Besides the lengthy process, all the filtration can leave the water supply tasting a little “plain” or “flat” to some homeowners.

Getting Rid of Excess Nitrates in Your Well Water FAQs

Still have questions about how to rid your well water of excess nitrates? We’ve compiled a list of the most frequently asked questions that people have about this topic. 

Will Boiling My Drinking Water Get Rid of the Nitrates?

Since water distillers boil your well water to get rid of contaminants, some people may wonder if they can skip the extra steps and do the boiling themselves. Unfortunately, just boiling your water supply on the stove won’t get rid of the nitrates, and you may even increase the concentration.

Some of the water may evaporate, which means you’re ending up with less water and the same amount of nitrates you started with.

Will a Regular Water Softener Get Rid of Nitrates?

While the ion exchange process borrows a lot of the same steps from water softening, you can’t use your water softener to get rid of nitrates. Traditional water softeners are set up to remove some contaminants, like calcium or magnesium, but not nitrates.

To effectively remove nitrates with ion exchange, you’ll need to make sure you have a resin bed with chloride ions, not the regular sodium ions.

What Should I Do if I Find Out My Water Supply Has Unsafe Levels of Nitrates?

If a test reveals that you have high nitrate levels in your water, you’ll want to stop drinking (and cooking with) your water supply immediately. Instead, stick to bottled water for cooking, drinking, and especially for mixing up baby formula.

From there, it’s a good idea to try and determine the source of the issue. It could be that there’s a damaged septic tank nearby, or the area that you live in has naturally higher levels of nitrates in the soil.

You’ll also need to treat your water with one of three methods above as soon as possible – but even after treating the supply, don’t begin using it again until a second test confirms your nitrate levels are now safe for drinking.

Photo of author
Craig Smith
Craig got his start in water working in the swimming pool and spa industry. Water treatment would grow into his main career but he ended up working in the pool industry for over 26 years where much of his time was spent balancing the water in customer's swimming pools and installing water filtration equipment. Craig offers an abundance of water treatment knowledge after helping homeowners get pure water for 26 years.

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