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How to Test Drinking Water Quality in Your Home: The 2020 Definitive Guide

How to Test Your Drinking Water Quality

This is a complete guide to home drinking water testing in 2020.

If you are concerned the tap water in your house might be contaminated, use this guide for actionable tips on how to test your water quality and what to do with the results.

Let’s dive in.

Is my drinking water safe?

The popularity of home water improvement systems has soared over recent years, with more and more homeowners opting to install a water filter, reverse osmosis unit, ionizer, softener or distiller in their home.

This might have left you confused – why do so many people feel the need to improve drinking water that’s supposed to be safe already? What’s the problem?

There should be no real problem with drinking water that has been processed at a water treatment plant… right?

how to test drinking water

After all, the purpose of water treatment is to remove contaminants and make your tap water safe to drink. This includes some chemicals, metals, and microorganisms that could make you ill.

However, that’s not to say that water treatment does a thorough enough job to completely remove these contaminants, which is why so many of them remain in our drinking water in trace amounts.

Remember also that water needs to travel to your home from these treatment plants, where it’s got a high chance of picking up metals and bacteria from pipes along the way.

There’s a lot of controversy around whether or not drinking small traces of contaminants is a health risk. Some research suggests that chemicals like chlorine might cause health problems like cancer, while lead can cause long-term harm like high blood pressure and kidney damage.

Which brings us back to the question at hand: “how can I test drinking water in my home?”

Lets start with some free data

EPA consumer confidence reports

The EPA, otherwise known as the Environmental Protection Agency, is a US body that requires all community water systems send out a water quality report, or consumer confidence report, on an annual basis.

Understanding how to read this water report will help you to get a better idea about exactly which contaminants are present in your water.

Need the consumer confidence report (CCR) for your area? Find your local CCR here

The tool can be a bit cumbersome to use.

You would think if you type the name of your city the results will show up. Not so much.

I found it easier to identify my local CCR using these steps:

  1. At the initial search, just select your State, but don’t specify any other search criteria
  2. When results are displayed, sort the ‘Population Served’ column in descending order
  3. Look in the ‘Water System Name’ column for your municipality
  4. Click the link in the ‘CCR Website’ column to see your local CCR report

Find your local ccr

A consumer confidence report can be presented in various formats, but the information given lists the different contaminants, chemicals, and by-products that your water contains after treatment.

These contaminants will have been identified through the municipality’s own water quality testing process.

denver water quality report

The report will detail the units of the contaminants, letting you see the total quantity in your water, usually in ppm (parts per million). It should also show the MCLG, or maximum contaminant level goal. This is the maximum level of a particular contaminant that can safely exist in water for drinking.

Another key item to look out for is the “violation” column of you table, which shows whether your local area’s water supplier produced water that contained a contaminant that surpassed the MCLG.

The “source” column is also useful for finding out where a particular contaminant came from, whether it was naturally occurring, added during treatment or a result of industrial contamination.

When do i need to test my water?

The issue with water quality reports is that they only indicate the level of contaminants in water at the time of treatment.

These reports can’t take into account the journey your water has to go on to reach your home, through underground pipes and plumbing systems that don’t get replaced in years.

It’s during this journey that water can pick up additional contaminants in potentially harmful levels, including lead and microorganisms like bacteria. The only way to really know whether these contaminants are present in your water is to test your water quality.

drinking water pipes
Water can become contaminated after treatment on its way to your home

Even if you’re not worried about the addition of contaminants to your water on its journey to your home, you might just want to test your water quality yourself for assurance that your water quality report is accurate, or even just because you’re interested to know how your home’s water compares to a friend’s or a family member’s.

You might be particularly interested to test your water quality if your water has an unpleasant taste or smell that suggests it’s high in a contaminant like iron or sulfur.

These contaminants aren’t harmful in traces, but their impact on water taste is one of the biggest motivators for people to ditch the bottled water alternatives and buy their own water filter.

How does drinking water become contaminated?

Drinking water can be contaminated at any stage of the water treatment process, including before and after.

The very first time your water will come into contact with contaminants is when it exists naturally in a river, stream or reservoir.

Think about all of the elements this water is exposed to – environmental pollutants, animals, sediment like soil and other organic material, and even surface runoff, which may add nitrogen, bleach, salts, pesticides, herbicides, metals and toxins to the water.

how to test water quality
Runoff in cities contributing to water contamination

Water is then taken into a treatment plant, where the majority of these contaminants will be reduced, but not fully removed. During the treatment process, chemicals like chlorine are added to water as a disinfectant.

Treatment plants rely on chlorine to remove pathogens like bacteria, viruses and protozoans, which could cause disease if they were left in drinking water. The problem is, this chlorine is never removed from the water, which only results in further contamination.

drinking water treatment plant
Drinking water is treated with chlorine

Once it’s been treated for drinking, water travels through metal pipes underground, which sometimes contain materials that may leach into water.

If your tap water is coming out slightly brown, it’s a sign that it contains iron from the pipes leading to your home. Lead and microorganisms can also contaminate water from plumbing pipes.

Common drinking water contaminants

There are several types of contaminants that are commonly found in drinking water. A contaminant is defined as any physical, chemical, radiological or biological substance in water – essentially anything other than water molecules.

Here is a breakdown of the different contaminant types and how they affect water:

Physical substances

Physical substances usually affect the appearance or make-up of water. They’re larger in size and may be noticeable to the human eye.

Examples of physical substances include soil, rust, dirt, sand and organic material from soil erosion.

These substances are usually not harmful in water, but they don’t taste great, and can reduce the quality of water. The water treatment process should remove the majority of them, but many water suppliers still provide water which contains traces.

Mud and dirt are physical contaminants

Chemical substances

Chemical contaminants in water may be naturally derived or man-made. They can make their way into water from surface run-off, or when added to water during the treatment process.

Examples of chemical substances include pesticides, metals, salts, nitrogen, toxins, bleach and chlorine.

There is debate over whether certain chemicals are too harmful to be allowed in drinking water at all. Chlorine, for instance, is thought to cause a number of illnesses, and is particularly harmful when breathed in. However, you will usually find traces of all of these chemicals in your home’s water supply.

chemical water contaminants
Pesticides pose risk of chemical contamination

Radiological substances

Radiological substances are unstable atoms that emit radiation into water. In most areas of the United States, low levels of radiological contaminants are found in drinking water. Usually, these substances aren’t present in high enough quantities to produce radioactive effects, but there is concern over the chemical effects they may display.

Examples of common radiological substances in drinking water include isotopes of radium, uranium and radon, as well as cesium and plutonium.

Biological contaminants

Biological contaminants are microorganisms that live and reproduce in water.

They’re present in most natural water sources, like rivers and lakes, and are reduced in the water treatment process. However, water treatment doesn’t remove all biological contaminants, and there’s a good chance that more contaminants will enter water on its journey to your home.

Examples of the biological contaminants found in water include

  • Bacteria, like Shigella, E-coli, Vibrio, and Salmonella
  • Viruses, like the rotaviruses
  • Protozoans, such as Entamoeba and Giardia.
biological water contaminants
Bacteria and viruses can contaminate drinking water

Heavy metals

It’s worth also being aware of the numerous heavy metals that most drinking water contains. The common heavy metal pollutants are arsenic, cadmium, chromium, copper, nickel, lead and mercury.

These are introduced into water naturally as a result of weathering and volcanic eruptions, or from human activities like mining and processing.

How to test drinking water in my home?

There are a number of different ways to test your home’s drinking water, whether you choose to do it yourself or entrust the job in a professional organization. Most water testing methods are quick and simple to carry out, although some processes do require more time or cost more money.

Knowing how to test drinking water is a good place to start before you take any further steps for water improvement.

Here are some of the most popular methods of testing your home’s drinking water:

Send Water samples to a lab for testing

If you don’t know what contaminants you want to test for in your water, or you just want to test for everything, the best thing to do is to send a sample of your water to a reputable local laboratory for testing.

These lab results will indicate a wider range of elements in your water when compared to home testing kits, which often just test for certain contaminants.

Laboratories that offer water testing usually require that you follow specific instructions to ensure your water can be tested to the highest accuracy. You’ll normally need to refrigerate your samples before you send them off, and get them to the lab within 24 hours.

Most labs provide their own sample containers, which will be sent out to you ahead of time. The best thing to do is to give your chosen laboratory a call and discuss the process of sending in a sample, as all labs work slightly differently.

laboratory water testing
Lab testing is the most comprehensive method

Hire a professional water analysis company

If you’re using a water source of your own, such as a well water source, you can hire a professional to visit your home and carry out in-depth well testing to ensure your water is safe to drink.

Well water testing is essential if you want to make sure your water source doesn’t contain contaminants that might cause serious illness.

You’ll need to factor in for regular well water inspection to ensure that your water remains clean and contaminant free.

Regular private water supply testing is recommended every 12 to 14 months.

A well water inspector can use specialist equipment to monitor the levels of specific contaminants in your water, and determine whether these are present in safe or dangerous quantities.

Your well water inspector might choose to send your water samples to a lab, where they can be examined in more detail. It’s worth requesting this from your inspector if you want to know exactly what your water contains.

If you don’t use water from a private source, but are considering a home water treatment unit, getting your water tested professionally is still a good idea. You’ll be able to find out what’s in your water and decide what you might want to remove, which will help you make more informed decisions when it comes to purchasing the best water filtration system for your needs.

Water test kits

One of the simplest methods of testing your water is to use an at-home water testing kit.

Different kits are designed for testing for different elements in your water. Some kits test your water’s pH, while others test for particular contaminants like lead, bacteria, sulfur, chlorine and dissolved solids.

Many kits test for a number of contaminants in one, but keep in mind that no testing kit will be able to inform you of the full range of contaminants in water. It’s thought that a single sample of drinking water contains hundreds of different contaminants, and most home water testing kits aren’t advanced enough to detect them all.

If you’ve never used a home water testing kit before, it’s a good idea to start with a standard kit that tests for anywhere from 6 to 10+ contaminants. Usually these are the most common contaminants found in drinking water, like lead and chlorine, so this sort of testing kit should give you a good insight into your water quality.
drinking water test kit

Another option is to choose a testing kit that’s designed for testing for a specific contaminant in your water.

If you think that your water contains high quantities of sulfur or iron, for example, which both affect the taste of water, you can use a testing kit to give an indication of exactly how much of these specific contaminants your water contains.

Keep in mind that water testing kits don’t give the most accurate representation of what’s in your water, but they’re a good place to start.

Let’s look in more depth at the most common contaminants that a testing kit can test for:

  • Bacteria – which may be harmful or disease-causing.
  • Iron – can affect water taste and leave stains or rust on surfaces.
  • Chlorine – which affects water taste and is harmful in larger quantities.
  • Sulfur – either naturally occurring or caused by bacteria. Gives water a rotten egg taste.
  • Lead – toxic in larger amounts, can give water a metallic taste.
  • Hard water minerals – calcium and magnesium, responsible for limescale issues.
  • Sediment – such as sand or grit, which affects the overall quality of water.

Test strips

Test strips are most commonly used for determining your water’s contaminant levels. Directions for how to use these strips may vary from kit to kit, so read your instruction manual carefully, even if you’ve used a testing kit in the past.

You can use test strips to test for chlorine, water hardness, water pH, water bacteria, and more general water analysis.

A testing kit will usually come with several strips that are designed for indicating different contaminants in your water.

To use the strips, you’ll need to dip them in a sample of your water (the fresher the better), and wait for it to turn a certain color shade. This usually takes several seconds to several minutes, although you should keep your strip submerged for the length of time advised in your kit’s user manual.

You’ll then compare the shade of your strip to the color chart provided with your testing strips. The chart will display a range of colors, which each indicate different quantities of the contaminant in your water. This gives an indication of how much of a contaminant your water contains, but isn’t the most reliable, especially as we all see colors slightly differently.


drinking water test strips

Color disks

Another low-cost, simple way to test your water quality is to use a color disk.

Color disk kits usually contain a liquid or powder reagent and a reusable plastic tube.

You’ll need to add the appropriate amount of reagent to the tube, along with a sample of your drinking water.

The water will slowly start to change color.

When this happens, leave it for a minute or two, then place the tube inside a clear viewing box.

This viewing box contains a plastic color wheel displaying a variety of colors. You should rotate the wheel until you find a shade that is most similar to the color of your water. This will indicate the concentration of the contaminant you’re testing for in your water.

Color disk kits are a little pricier than testing strips, but are generally the more accurate of the two. However, there’s still the issue of varied human eyesight, and you might not be able to precisely match up a water shade to a shade on the color disk.


drinking water test color disk

Digital instruments

If you want to get slightly more technical with your drinking water testing, you can use a handheld digital instrument to give you an electronic reading of any contaminants found.

They provide the most accurate reading out of all the at-home water testing kits available, and are more commonly used at an industrial level. However, there are cheap at-home digital water testing instruments available as well.

Common forms of digital testing include portable digital meters, colorimeters, and photometers. They require the most delicate use, but their more precise results make them worth the extra effort.

You’ll usually need to calibrate your digital water tester before you can use it. Most testers also require batteries or some form of electric charge. To maintain your water tester over time, you might need to replace certain components according to your kit’s instruction manual.


digital water tester

How do I remove contaminants from my tap water?

Now that you’ve tested your water, there’s a good chance that you want to remove certain contaminants from your drinking supply. Luckily, there are plenty of options available today for doing just that.

Thanks to the wide variety of home water improvement methods available, you’ll be able to find a treatment that suits the needs of your household the most.

We’ve covered the main filtration methods below:

Point of entry (POE) Whole House Water Filters​

Point of entry filtration allows you to filter your water at its earliest entry point into your home. This style of water filter is connected to your main water pipe before it splits off to the different areas of your home, and comes in a number of different filtration types.

The type of point of entry filter you opt for depends on your budget and your filtration needs.

Reverse osmosis systems, for example, can cost up to $3,000, but offer the most thorough contaminant removal – although they are the only filtration method to waste water during the process.

Whole house carbon filters are a lot more wallet-friendly, at around $1,000, but don’t work quite as efficiently.

Next generation filter technology is a good mix of the two, but is still quite high in price, at around $2,000.

water purification process

Carbon based systems

Whole house carbon based filters are the lowest cost point of entry filtration option, and combine several filters, including an activated carbon filter, to reduce common contaminants from water.

In a carbon filtration system, water enters the unit and passes through a pre-filter, which removes larger particles and sediment.

It then flows through an activated carbon filter, which has a large surface area for trapping a wide variety of contaminants in its pores, including chlorine, pesticides and copper.

Finally, water travels through a post filter, which polishes water and removes any remaining sediment before it passes through to the rest of your home.

Reverse osmosis systems

Reverse osmosis filtration is one of the costlier water improvement methods, but is also one of the most thorough.

In the reverse osmosis process, water passes through a number of different filters, as well as a semi-permeable reverse osmosis membrane, which can remove up to 99.9% of total dissolved solids from water.

Reverse osmosis systems usually include a pre filter and a carbon filter, for removing larger sediment, chemicals like chlorine, and some metals from water.

Water is then forced through an RO membrane at a high pressure, which traps contaminants in the membrane, only allowing water particles to pass through.

Finally, water passes through a post carbon filter to remove any particles that may have been small enough to pass through the RO membrane.

reverse osmosis filter

Next-generation filter technology

The final water quality improvement method for the whole home is next generation filter technology.

A next generation filter normally uses three stages of filtration: a pre-sediment filter, an electro-charged sub micron filter, and a catalytic carbon filter.

These filters combined remove a broad spectrum of contaminants from water, including microorganisms, pesticides, chemical compounds, rust, dirt, and heavy metals.

Point of use (POU) water filters

Point of use water filters are designed for use in a certain location within your home.

As most people prioritize clean water for drinking, you’ll normally always find that point of use filtration systems connect up to your kitchen sink faucet.

There are three main types of point of use filters:

They’re all designed to remove contaminants from water, but vary in price and efficiency.

Water filter pitchers are the cheapest option of the three, costing around $30 to $70, but usually contain only one carbon filter, making them a less efficient option.

Countertop systems are slightly more expensive, costing several hundreds of dollars, but do a better job at contaminant removal.

Under sink systems work similarly to countertop systems but can cost slightly more money, especially if they use a reverse osmosis membrane.

Under sink systems

An under sink water filter is a system that’s installed underneath a kitchen sink and connected to the sink via the cold water line.

This type of filter removes contaminants from water before it can reach your kitchen faucet. Some systems require that you install a separate faucet for dispensing the system’s filtered water.

An under sink filtration unit combines a number of filters to produce cleaner, safer drinking water.

These systems usually include a pre-filter for removing sediment, one or two carbon filters for removing chemicals and organic compounds, and a post filter for polishing water before it reaches the faucet.

Some under counter systems include a reverse osmosis membrane, which can remove up to 99% of all total dissolved solids.

Normally, an under sink water filter uses a storage tank to hold filtered water until you turn on the faucet.

under sink water filter reviews

Countertop systems

Countertop filtration systems are designed for setting on your kitchen countertop near your kitchen sink.

You’ll need to connect a countertop filter up to your water line, either at the faucet or the cold water line, to divert water into the system for filtration.

Some countertop water filters are connected to a separate faucet at your kitchen sink, while others dispense water straight from the unit itself.

These systems usually contain pre-filters, carbon filters, and post filters, which work to remove chemicals, heavy metals, microorganisms, and other compounds from water.

Countertop Filtration System

Water filter pitchers

Water filter pitchers are a type of jug that filter water when it’s added, making it cleaner for drinking.

Filter pitchers contain a carbon filter, which has a large surface area that acts as a sponge, absorbing contaminants like chlorine, heavy metals, pesticides, and other organic compounds that might be present in water.

When you add water to a water filter pitcher, you’ll need to wait for around five minutes for the filtration process to take place.

As a filter pitcher isn’t connected to a faucet, you can take it with you around your home – but keep in mind that you’ll need to manually refill the pitcher every time you empty it out.

Brita 10 Cup Grand review

Point of entry vs Point of use: Which is right for me?

If you don’t know whether a point of entry or point of use water filtration system is best for your needs, it’s worth considering what really matters to you.

A point of entry water system will give you the same benefits as a point of use system, plus a few more.

If you just want to enjoy clean, better tasting drinking water, without the additional benefits around your home, a point of use filter should be fine for you.

With a water filter that’s connected to your kitchen sink, you’ll be able to use clean water for drinking and cooking. You can also connect many kitchen sink systems to your refrigerator, ice machine and coffee maker for extra convenience.

If you want to enjoy clean drinking water and reap the filtered water benefits while you’re taking a shower, doing the laundry, cleaning your home, washing the dishes and boiling the kettle, a point of entry water filter is for you.

This produces filtered water that you can use throughout your home, which can help your appliances to last longer, prevent damage inside your plumbing, eliminate limescale, and enable your home to run more efficiently.

Obviously, there’s a significant difference in price between the average point of entry system and the average point of use system. You’ll need to factor in a bigger budget for a whole home water filter.

No matter which filter type you choose to buy, they all have things in common. All systems, for example, will require regular filter replacements to ensure they continue to run properly.

The lifespan of your unit’s filters depends on the specific product and filter type, but generally, you can expect to change most filters after a maximum period of 6 months.

Some filters, like the carbon filters in water filter pitchers, will require changing even more frequently – normally once every 4 weeks.

Ultimately, choosing a water filter for you comes down to your own specific needs. It’s important not to get sucked into a clever marketing strategy that makes you feel like you need a filter system even if you really don’t. Make sure to read up on impartial reviews before you make a buying decision, and get in touch with a filter’s manufacturer if you want to know more about the product they’re selling.

How to test your water: Final thoughts

Testing your water quality, no matter which method you choose to go with, can help you to determine which contaminants you want to remove using a water filtration system. Knowing how to test your water quality will give you more freedom when it comes to choosing a method of testing that you think will offer the best results.

Many types of water testing are low in cost and can be carried out at home. While they don’t give the most accurate or thorough results, water testing kits and color wheels are great methods to start with if you’ve never tested your home’s water before.

From there, if you’re looking for something more specific, you can request professional testing or send a water sample off to a laboratory.

Remember that you’ll always have free access to your local authority’s water quality report, which can give more detailed information on the contaminants your water contains.

If you notice there’s a specific contaminant that your water contains a lot of, you can then decide on a filtration method that’s most effective at reducing this contaminant from water.

If you’d like more information about your water quality, or you’ve noticed a change in your water, you can get in contact with your public water utilities company. If you have a private water supply, like well water, it’s your responsibility to ensure that your drinking water is safe for use.