How to Test a Well for Contaminants: A Homeowner’s Guide

Laboratory technician holding a flask and testing water quality in a laboratory setting.

If you own a property with a private water well, congratulations! A healthy well can be a wonderful source of pure water for your whole family and all your pets. But a private water well must be maintained properly to provide that healthy water, and that includes a regular schedule of water quality testing. 

There are no local, state or federal agencies that control the quality of your well water. Therefore, your water quality is entirely up to you. If you are new to owning a private water well, then we can help you learn about the importance of well water testing and what contaminants can be dangerous for your family. This guide will provide you with the basics you need to know to maintain a fresh, healthy water supply. Use this guide as a starting point to keep your well healthy!

Which Harmful Contaminants Could Be in Your Well Water? 

Some contaminants affect the taste or smell of your water and others can cause health issues ranging from digestive irritation all the way to cancer. A household with new babies, elderly individuals or someone who is immunocompromised must make a greater effort to provide pure water. There are even some contaminants that can cause problems with your plumbing system. When you’re starting out, it’s important to get familiar with common contaminants, the problems they can cause and how they can be removed from your well water. 

Professional water testing is the best way to tell you if any of the following harmful contaminants are in your well water. 

Microorganisms: Well water can be a home for a variety of microorganisms. Some are harmless but can provide an indication of a more serious contamination. Here are the microorganisms you should check for in your water.

  • Coliform bacteria and E. coli. These are two large groups of bacteria, most of which are harmless. However, if you find coliform or E. coli bacteria in your water, it is typically a sign of some kind of fecal contamination. The source could be animal waste making its way to your well during heavy rains, or septic system leaks on your property or one that is nearby. 
  • Viruses and parasites. These can also come from surface flooding or septic failures. Bugs or small animals making their way into your well through small openings can also introduce viruses and parasites into your well. You’ll need to disinfect your well but also look for and repair any ways that pests can make their way in. 

Nitrates and Nitrites: Nitrates like potassium nitrate and ammonium nitrate can enter your well in runoff from agricultural operations. Both fertilizers and animal waste can release these toxic substances that interfere with the body’s ability to carry oxygen. Please note: This contaminant is particularly dangerous for new babies. Leaking septic systems can also release nitrates into groundwater, which then makes its way into your well. There are also natural sources of nitrates in soil. Once nitrates reach groundwater, they dissolve easily and can be carried for miles until they reach your well. 

Heavy Metals: These metals in your drinking water can come from natural deposits or even from your own plumbing system. The types of heavy metals you might find in your water include lead, arsenic, cadmium, chromium, copper, mercury and selenium. Heavy metals can be toxic, even if they are only present at low concentrations. They can cause kidney and liver damage, anemia, developmental delays in babies and children, and cancer. If your water is acidic, it is more likely that your water will leach metals like copper or lead from your pipes. 

Organic Chemicals: Organic chemicals are those chemicals that contain carbon atoms bonded to other elements. This class of chemicals includes substances like these:

  • Pesticides
  • Herbicides
  • Solvents
  • Industrial chemicals
  • Petroleum products

Obviously, you wouldn’t want any of these chemicals in your well water but they can make their way into your well due to agricultural runoff, industrial spills, underground storage tanks that are leaking and improper disposal. Many of these chemicals are cancer-causing or toxic to the nervous, reproductive or immune systems. 

Radionuclides: Included in this class are:

  • Radium
  • Uranium
  • Radon

These are all naturally occurring radioactive materials that are found in bedrock across the country. Very small quantities are not problematic, but higher concentrations are a cause of lung cancer. 

What Other Water Contaminants Are Not as Harmful But Still Cause Problems?

Sulfates, iron, calcium and magnesium are not as likely to cause health problems but can cause problems in your home. 

  • Sulfates: These minerals can change the taste and odor of your water. They can also cause diarrhea, which can be harmful for babies who might become dehydrated. 
  • Iron: Elevated levels of iron are not usually harmful but can cause water to have a metallic taste. Laundry and dishes can be stained. A few people with a genetic condition called hemochromatosis should avoid high iron levels. 
  • Calcium and magnesium: These minerals enter groundwater as it passes through mineral deposits. Once they are in your plumbing system, they can build up inside pipes and on plumbing fixtures in your home. This buildup can necessitate plumbing or appliance replacement. These minerals can also cause cloudy deposits on dishes and shower walls. Laundry will gradually look less clean. 

How Can Acidic Water Affect Your Home or Plumbing System?

Some contaminants cause your water to be more acidic, which then, in turn, can cause plumbing system problems. As water picks up carbon dioxide, iron and manganese, the pH is lowered, which makes the water more acidic. Also, if the water passes through decomposing plant material, it can become more acidic. Fertilizers and pesticides can also make water more acidic.

As acidic water passes through your pipes, the water will leach metals out of the components of your plumbing system. Copper, iron, lead, zinc, manganese and even nickel may be added to your drinking water and, therefore, to your family’s bodies. 

What Harm Can Alkaline Water Do To Your Plumbing System?

Alkaline water typically contains high levels of calcium and magnesium. These minerals can end up deposited on the inside of the pipes that are part of your plumbing system or your appliances. Mineral deposits in your appliances can shorten their lives or require expensive repairs. Alkaline water is typically not harmful but can cause digestive upsets if the pH is too high or too much of this water is drunk. 

How Can You Use Water Testing to Improve the Quality of Your Water? 

When you find out exactly which contaminants are in your water, you can design a filtration or water treatment system that will remove the specific contaminants in your well. There are no filters that correct every problem your water can have. You might need a multi-step process to give your family healthy water all year round. If you don’t test your water before designing your system, you could waste money on the wrong types of filters that won’t remove the harmful contaminants found in your groundwater or plumbing system. 

How Should You Choose a Water Test?

You might be tempted to choose an inexpensive water test from a home improvement store. These tests will only look for a dozen or so contaminants. Additionally, there won’t be an accurate measure of the quantity of each contaminant. Therefore, you can’t judge the seriousness of contamination. 

Instead, look for a professional water testing company that also provides water tests for municipalities and industries that rely on pure water. A professional lab will have the equipment and expertise to provide accurate results for 200 or more possible contaminants. At ETR Laboratories, we have more than 100 different water tests that provide accurate test results for the wide variety of substances that could be in your well water.

What’s the Best Way to Schedule Your Water Testing? 

If you have never tested your well water, your first test should be as comprehensive as possible. This test will tell you what you need to remove from your well and will guide you as you plan a filtering system. After the initial test, plan an annual test so you can detect any changes to your water quality. Your well water can be damaged by industrial chemical spills, changes in agricultural operations, damage to the well head, floods, snow melt, nearby construction, a leaking septic tank on your property or one nearby and a dozen other causes. A more limited, basic water test annually will let you know if there have been any changes to your water quality. 

How Should You Plan Your Water Treatment System? 

Once you have the results of your comprehensive water test, you will need to match up the contaminants you need to remove with the type of filter that will remove those specific substances. When planning your system, consider these filters or water treatment processes. 

Carbon-based filters: This is the most common type of commercial filter. Activated carbon filters will remove: 

  • Organic compounds such as pesticides, herbicides and industrial solvents
  • Chlorine and the byproducts of disinfection with chlorine
  • Radon (some carbon filters)
  • Compounds that affect water taste and odor
  • Lead, mercury and copper (depending on the design—check its specifications)
  • PFAS (per- and polyfluoroalkyl substances), industrial chemicals of growing concern

Reverse Osmosis: This is a highly effective purification technology. But be forewarned that there is a lot of wasted water that could increase your water bill.

  • Dissolved salts and minerals like sodium, calcium, magnesium, potassium and chloride
  • Heavy metals like arsenic, lead, mercury, cadmium, barium, chromium, copper, iron, manganese, aluminum and zinc
  • Nitrites and nitrates
  • Radionuclides, including radium and uranium
  • PFAS
  • Many pesticides, herbicides and other organic compounds
  • Cysts, parasites and some other microorganisms
  • Suspended particles that cause cloudiness

Ultraviolet Water Treatment: This is a disinfection process that works by exposing the flow of water to ultraviolet light. These microorganisms are either killed or inactivated by ultraviolet light:

  • Bacteria
  • Viruses
  • Fungi
  • Parasites and other microorganisms

Ion Exchange Systems and Water Softeners: These systems remove calcium and magnesium before they can damage your plumbing and appliances. Barium and radium can also be reduced by these systems. However, a water softening system will add sodium to the drinking water. Anyone on a low-sodium diet may need to add another type of filter to remove it. 

Distillation: Distillation systems are not very common. They will remove minerals, many bacteria, viruses and some chemicals. Substances that may only be partially removed are chlorine, byproducts of disinfection and organic compounds. 

ETR Laboratories Is Your Trusted Source for Accurate, Professional Water Testing

Thousands of private well owners, municipalities and industries that need pure water rely on ETR Laboratories to ensure the quality of their water supply. When you order a water test from ETR Laboratories, you are ordering directly from the lab that does the testing. A water test selected from a website you search for online may simply be a middleman that sends its tests to ETR Laboratories for processing. Order from the experts with years of experience helping professionals like real estate agents and well drillers ensure the quality of their transactions. 

If you are testing your well water for the first time, the right test for you is the comprehensive water test that will check for 249 contaminants or water attributes. Once you have these results, you will know exactly what needs to be filtered out of your water. 

When you are ready to run an annual water test to check for changes in your water quality, choose the basic water test. ETR Laboratories also offers more than 100 other tests for individual contaminants or tests that may be needed in specific situations. 

To ensure that your family always has the freshest, purest water possible, consult ETR Laboratories today.