Water Quality Tests: What To Consider And How To Do It

Drinking enough water has great health benefits, but it depends on the quality of water you drink. It’s important to test your water for specific contaminants like heavy metals, microorganisms, and other chemicals, which can cause health risks. Fortunately, there are lots of options to test you water.

Water quality can be tested using DIY home kits, send-away kits, or by hiring water professionals. Send away kits and water professionals provide more comprehensive, reliable, and readable results, while in-home kits are inexpensive and quick.

In this article, I discuss how, why, and when you should test water quality. Each method has its own pros and cons so that you can make an informed decision.

I’ve also detailed the common contaminants that you find in water, and how they affect you.

Water Quality Testing Methods

Do-It-Yourself Home Kits

A DIY water testing kit is a quick, budget-friendly way to test your water, especially for lead contamination.

These tests consist of color-changing paper strips that you drip and shake in water for a few minutes.

Then you can compare the color change against a chart to determine how contaminated your water is.

It is very important to follow the manufacturers’ instructions to the T when it comes to DIY kits.

DIY kits are best used as the initial step in identifying the contaminants in your water. This can then be followed up with a more detailed professional report so that you can choose the best purification system if required.

For bacteria, lead, pesticides, nitrates/nitrites, and chlorine

The First Alert WT1 Drinking Water Test Kit from Amazon is a great all round home test kit that is well-trusted.

For water hardness

The JNW Direct Water Hardness Test Strips (Amazon link) help you determine how hard your water is. You can use this to test the performance of your water softener.

For well water

The Health Metric Well Water Test kit checks the level of nitrates, alkalinity, and hardness.


  • Most inexpensive option
  • Results are instantaneous
  • Most preferred to detect lead


  • Not very detailed
  • Results can be difficult to read or interpret correctly
  • Results can be subjective – not interpreted by professionals
  • Prone to user error
  • Usually needs a follow-up by a professional

Lab Test Kits

Lab test kits are send-away kits – here you collect water from your home in sample tubes and ship them to a certified lab.

Some kits also come with a mailing label so you can ship them the samples easily.

Each kit comes with multiple sample tubes to collect water so that you can test for multiple contaminants like heavy metals, microorganisms, and organic compounds.

These test reports are more detailed than at-home kits because they have more information about the health risks associated with contaminants in YOUR water (as opposed to a general list in in-home kits).

Some kit providers like SimpleWater Tap Score also provide online support.

If your on a public water supply, you can buy the SimpleWater Advanced city Water Test on Amazon.

However, you can get the same Advanced test cheaper by following my link below:

Test Your City Water Today!

If you use well water:

Test Your Well Water Today!

The Safe Home Ultimate Drinking Water Test Kit tests over 200 contaminants, including organic, inorganic, and heavy metal contaminants. This kit from Amazon also comes with an in-home coliform test. This test can be use on city water or well water.


  • More comprehensive than home tests – tests 60-200 contaminants
  • More accurate than home tests
  • Less expensive than professional water experts


  • More expensive than home-tests
  • Results take more time than DIY tests
  • Samples may be contaminated if taken incorrectly
  • May require a visit to the post office if your kit doesn’t come with a paid shipping label
  • Some reports may be hard to interpret unless you know what it all means

Water Professionals

Water professionals are locally available experts that conduct home visits. While they are expensive to hire, they provide comprehensive testing services.

They collect samples themselves and send you a detailed report after assessing your environment to determine the possible sources of contaminants.

Water treatment representatives can be hired to provide aesthetic water solutions, while certified water specialists help you with issues related to contaminants.

A master water specialist is a go-to for advanced water treatment issues. These professionals can also be hired by organizations to solve their commercial water treatment issues.

You can find certified water professionals from the Water Quality Association, a non-profit guide for consumers and organizations.


  • Comprehensive, customized solutions
  • Personal accountability
  • Site visits to assess the environment


  • More expensive than lab kits or home kits

How to Collect a Water Sample

Be it with an in-home test kit or a sample sent to a lab, here’s what you should know about collecting a water sample from your tap or well.

  • Collect the water at the source, before it passes through any filtration or purification system inside your house. This helps you get an idea of what contaminants your water has so that you can invest in the most suitable water treatment plan. So, collect the water at the source line before bypassing additional home treatment systems.
  • If you are collecting water from the tap, make sure to collect only cold water, because hot water trapped in the collection flask may develop bacterial colonies.
  • Some collection flasks will already contain chemicals that help stabilize the water sample, so don’t wash the containers out before filling unless it specifies to in the instructions.
  • If you do wash the collection flask with detergent or bleach, make sure you rinse and wipe it completely – trace chemicals on the flask can give you incorrect test results.
  • If there are water stabilizing chemicals in the container, try and avoid losing any by filling the bottle slowly. You can even use the lid to pour in the last amount more carefully.
  • Air bubbles can interfere with some water analyses. Generally, you will need to fill the sample container all the way up – unless specified otherwise. Fill the container so there is a convex meniscus at the top of the bottle before putting the lid on. You may also find tiny bubbles trapped on the side of the container, so give it a gentle tap to release them.

Why Should You Test Water

While the USA has one of the safest water supply systems in the world, the quality of the water differs across the country.

Public water supply quality is regulated by the SDWA (Safe Water Drinking Act) of 1974, but even then, your water may be contaminated due to faulty plumbing fixtures or leaks.

Not all tap water is drinkable – public water treatment facilities in some cities may not be adequate to purify and filter water.

This interactive tap water contamination map by the National Drinking Water Alliance can give you more insight into any media reports relating to the public water supply of your city.

Private wells are not regulated by the SDWA, which means that it is up to you – the owner and consumer – to test the quality of well water.

Well water may be contaminated by agricultural runoff, sewage seepage, bacteria, or corrosive plumbing, so it is recommended to test its quality regularly.

When Should I Test My Water?

While the SDWA requires public water systems to send a yearly Consumer Confidence Report (CCD) detailing water quality, it is recommended that you test your water at the point where it reaches your home. This is so that you can rule out the possibility of in-house contamination.

As a rule of thumb, test your water every time you move into a new living space. Having a clear picture of the most common contaminants in your water helps you pick the best filter and treatment system.

Test your water any time you find a change in the color, taste, odor, and feel.

If your building has plumbing that was installed before 1987, make sure to test the water for heavy metals – particularly lead.

If your living space is close to agricultural land, your water may be more prone to chemical contaminants and pesticides.

When it comes to private water supplies, aquifers, and wells, test your water at least once a year. If you have to get someone out for a well repair or maintenance visit, get them to test the water quality while they are at it.

We highly recommend testing well water if anyone drinking this water experiences gastrointestinal issues, headaches, nausea, or itchy skin.

Additionally, you should consider testing your well water in case you find any spillage of fertilizer, gasoline, or pesticides within 500 feet of your well.

You should also test your water if the area around the well has been flooded, or you find a human waste disposal/septic system field within 100 feet of the well.

Types of Contaminants

Heavy metals

Heavy metals are naturally found in the earth’s crust. These metals are toxic to humans – they bioaccumulate in the body over time and cause serious health problems.

While a few of these metals may be present in trace amounts in groundwater naturally, most heavy metals dissolve into the water due to leakage from waste disposal sites and corrosion of plumbing.

Test your water for heavy metals especially if your plumbing is more than 40 years old.

  • Arsenic: Arsenic usually dissolves into the water from natural deposits or pesticides. Ingesting too much arsenic may cause skin issues, diseases of the circulatory system, and an increased risk of cancer. The EPA recommends a maximum of 0.01 mg/L concentration of arsenic.
  • Lead: Lead in drinking water comes from corroded plumbing. The EPA has determined that there is no safe level of lead in drinking water. Children and pregnant women are most vulnerable to lead poisoning – lead can cause neurological, behavioral, and gastrointestinal problems.
  • Mercury: Mercury may be present in water as a result of landfill runoffs and discharge from factories. Mercury buildup in the body causes renal and nephrotic issues. The EPA does not allow more than 0.002mg/L mercury in drinking water.
  • Iron: While high amounts of iron in water do not pose a health hazard, it may cause dark stains on laundry and fixtures. It may also give the water a metallic taste. So, a level not exceeding 0.3 mg/L is recommended. 
  • Copper: One of the most common heavy metals in water, copper may leach from corrosion of plumbing fixtures and pipes. Short-term exposure to copper may cause gastrointestinal issues, while long-term exposure may lead to grave kidney or liver damage. The EPA allows a maximum reading of 1.3mg/L of copper.
  • Cadmium: Cadmium is found in galvanized pipes and plumbing fixtures and may leach into the water due to corrosion. Cadmium poisoning leads to kidney damage and other nephrotic issues. The EPA allows a maximum of 0.005 mg/L cadmium in water.


The most common bacterial test is for coliform bacteria. While coliform bacteria rarely cause diseases, their presence in the water should be a cause for concern. This is because coliform may signal the presence of other harmful pathogens (like E.Coli, salmonella, etc.) and fecal matter.

No amount of coliform bacteria is acceptable. Your test report will indicate an absence or presence of coliform.

In case the report shows coliform in your water, stop drinking it immediately, identify the sanitary defects, and disinfect your water.

Other bacteria tested include Giardia, Cryptosporidium, and Legionella. No amount of bacteria present in water is acceptable.   


  • Nitrates: Nitrates find their way into your water through agricultural and lawn runoff, as they are found in fertilizers and manure. Water high in nitrates may cause miscarriages in pregnant women and blue-baby disease in infants. The level of nitrates in water is measured in mg/L, and the EPA lists the safety level as 10 mg/L. However, a reading of less than 2 mg/L is optimal. 
  • Fluoride: Fluoride is artificially added to make teeth stronger, but too much of it in the bloodstream can cause bone and tooth disease. The EPA allows a maximum of 4 mg/L of fluoride in water.
  • Sulfates: Sulfates reach the water from dissolved mineral deposits and agricultural runoff. Sulfates may cause laxative effects, especially if you are unaccustomed to it. Water rich in sulfates may also lead to scaly buildup. A sulfate concentration reading less than 250 mg/L is optimal.
  • Chlorine compounds: Chlorine compounds may be found in water as a result of leakage from septic systems, landfills, fertilizer, and road salts. They may also be added to water during the disinfection process. Ingesting too many chlorine compounds may cause anemia, disorders of the nervous system, eye irritation, stomach troubles, and nose irritation.
    • Chlorides that leach from pipes may make your plumbing more corrosive. This in turn can cause heavy metals to leak into your water.
    • The amount of permissible chlorine compounds in drinking water are as follows:
Chlorine compoundPermissible levels in drinking water
Chlorite1 mg/L
ChlorineMaximum Residual Disinfectant Level 4 (4 mg/L)
Chlorine DioxideMaximum Residual Disinfectant Level – 4 (4 mg/L)
Vinyl chloride0.001 mg/L
  • Asbestos: Asbestos finds its way into water from asbestos cement fittings and fixtures. Ingesting asbestos may cause intestinal polyps and benign stones. The EPA recommends a maximum reading of 7 million fibers per liter


The Total Dissolved Solids (TDS) refers to the amount of organic and inorganic matter dissolved in the water solution. This includes mineral salts that may lead to scaly buildup in plumbing fixtures and humidifiers.

While drinking water with more than 500 mg/L TDS is not dangerous, the EPA recommends opting for less mineralized water.


This refers to the ability of the water to neutralize acids. Alkalinity results from dissolved carbonate and dolomite salts in the water. Usually, naturally hard water is highly alkaline. If your water shows high alkalinity but low total hardness, it has likely been treated with a water softener.

Alkalinity values are not indicative of health benefits, but highly alkaline water is flat and not very tasty.


Hardness is a measure of magnesium and calcium salts in the water. While hardness does not impact health, hard water can cause scaly buildup in plumbing fixtures and purifiers. Hard water also makes it difficult to clean and lather water. On the other hand, naturally soft water may be corrosive.

Your test report indicates hardness in mg/L. A reading less than 150 mg/L indicates soft water while one above 200 mg/L is hard water. The EPA recommends a maximum reading of 270 mg/L. 


pH measures the amount of hydrogen ions in water, indicating if it is acidic or basic. The more acidic the water, the more corrosive it is. A pH between 6 and 9.5 is acceptable.  


Turbidity refers to the cloudiness of water – how transparent and clear it is. Turbidity is an indicator of the amount of suspended solids in the water. Higher the turbidity, the higher the chance of finding disease-causing parasites. A reading of 1 Turbidity Unit (TU) is the maximum accepted value. 

Here is a contaminant cheat sheet summarized in a table.

ContaminantEPA Guidelines for Maximum Permissible Limit)Treatment Method
1Arsenic0.01 mg/LRO, UF, distillation
2LeadZeroRO, distillation, carbon filters
3Mercury0.002 mg/LRO, coagulation, carbon filters
4Iron0.3 mg/LWater softener, iron removal filter
5Copper1.3 mg/LRO, carbon filters
6Cadmium0.005 mg/LRO, distillation, carbon filters
7BacteriaZeroUV, distillation
8Nitrates2-10 mg/LRO, distillation
9Fluoride4 mg/LRO, activated alumina
10Sulfates250 mg/LRO, distillation
11Chlorite1 mg/LDistillation, RO
12ChlorineMaximum Residual Disinfectant Level 4Distillation, RO
13Chlorine dioxideMaximum Residual Disinfectant Level 4Aeration, distillation, RO
14Vinyl chloride0.001 mg/LRO, distillation
15Asbestos7 million fibers per literCarbon filter, RO
16TDS                  500 mg/LRO, distillation
17Hardness270 mg/LWater softeners, RO, distillation
18pH6-9.5Water softener/neutralizer
19Turbidity1 Turbidity UnitDistillation, UF, carbon filters

The Bottom Line

It is important to check your water for contaminants regularly. We recommend testing your water with inexpensive at-home kits at least twice a year. If your results are at all concerning, you can follow-up with a send-away kit or a water testing professional. This helps you stay healthy and hydrated!

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