Well Testing: 12 Things (2024) You Need To Know

If a well is the primary water source to a home or parcel of land that you’re interested in purchasing, you’ll want to be sure to have well testing done ahead of time.

After all, when using well water, you can’t make any assumptions about its purity.

You need to test the well to ensure that it’s safe for you and your family to use and consume.

In this blog, we’ll discuss the top things you need to know about well testing.

Let’s get started.

1. What is a well test?

A well test is a test that measures the presence and number of certain germs and contaminants in the water.

2. What does a well test check for?

Well testing checks for several water quality indicators (WQI) and contaminants.

WQI are biological or physico-chemical indicators that are easy to test for and may indicate the presence of toxins or disease-causing germs.

Fortunately, WQIs by themselves do not cause illness in most cases.

That said, you do want to test for them and make sure your water is safe.

You can visit the CDC’s page on Water-Related Diseases and Contaminants in Private Wells to read more about the germs and chemicals in drinking water wells and the illnesses that they cause.

3. What are some examples of well water quality indicators (WQIs)?

Here are some examples of water quality indicators that you may want to look out for…

bulletTotal Coliforms:

Coliform bacteria comes from animal feces, soil and plant material, and surface water that infiltrates the well.

While most coliform bacteria do not make you sick, testing for specific disease-causing microbes can be difficult since they are usually present in small numbers.

As a result, the total coliform bacteria count is tested instead.

If the count is high, then it’s a good possibility that harmful germs or parasites might be found in the water as well.

bulletFecal Coliforms / E. Coli:

Fecal coliforms are a type of coliform bacteria originating in the feces and digestive systems of animals (including humans).

E. coli is one of these fecal coliforms and may be tested for by itself.

As with other coloforms, fecal coliforms are typically harmless, but they do indicate that the water may be contaminated by sewage or feces, which can cause diarrhea, dysentery, and hepatitis.

It is important not to confuse this test for the usually harmless WQI E. coli with a test for the more dangerous breed, E. coli O157:H7.


The pH level of your water will tell you how acidic or basic it is.

Well owners like to test the pH level of the water because it can change how the water looks or tastes.

Additionally, if the pH of your water is too low or too high, then it could damage your pipes and eventually make you sick.

4. What are some examples of well contaminants?

Here are some examples of contaminants that you may want to look out for…


This is naturally found in a variety of foods.

High levels of nitrates in drinking water, however, can make you sick.

In well water, nitrates will come from private septic systems, wastewater, animal waste, flooded sewers, polluted stormwater runoff, fertilizers, agricultural runoff, and decaying plants.

This type of test is recommended for all wells, and if your nitrate level is higher than EPA standards, then you should look for other sources of water or ways to treat your water.

bulletVolatile Organic Compounds (VOCs):

VOCs are industrial and fuel-related chemicals that are harmful to your health.

The type of VOCs you’ll encounter ultimately depends on where you live.

Some examples include benzene, carbon tetrachloride, toluene, trichloroethylene, and MTBE.

bulletOther contaminants:

Other contaminants depend on your local area.

They may include lead, arsenic, atrazine, and other pesticides.

Check with your local health department to see what contaminants are an issue in your region.

5. What isn’t included in a well test?

It’s important to note that radon is typically not on the list of materials that are tested for in a standard well test.

But it’s very important to test for radon in your water supply as it is dangerous to your health.

Be sure to check whether radon is included in your test.

If not, it’s worth paying for an additional radon test.

6. When should you have your well tested?

You should have your well tested at least once a year for total coliform bacteria, nitrates, total dissolved solids, pH levels, etc.

If you suspect other contaminants, then those should be tested for as well.

A local expert from your health department will be helpful in this case.

They can help you identify whether you just need a routine check or if any local contaminants are of particular concern.

You may also need your well tested if:

bulletThere are known problems with well water in your area

bulletYou have experienced problems near your well (flooding, land disturbances, nearby waste disposal sites, etc)

bulletYou replace or repair any part of your well system

bulletYou notice a change in water quality (taste, color, odor, etc.)

7. Who should test your well?

State and local health or environmental departments will often offer to test private wells for nitrates, total coliforms, fecal coliform, volatile organic compounds, and pH.

To find someone to test your well, visit your local health or environmental department’s website or county government’s website to find out how to submit a water sample for testing at a state-certified (licensed) laboratory.

8. What should I know if I’m buying a property with a well?

If you’re buying a property with a well, you may be in some new territory.

Don’t worry!

We’ve collected some frequently asked questions, and we’re compiling them here, so you can read up on what you may want to know.

bulletIs well water safe to drink?

Yes! Water from a private well can be just as safe (if not safer) than municipal water.

To ensure its safety, you’ll need to regularly test the water.

bulletHow can I tell if my well water is safe?

The only way to know for sure if your well water is safe is to have it tested.

Note that some contaminants will change the appearance, smell, or taste of your water.

If this is the case, then you’ll want to send a sample to your state health department or call an inspector immediately to come out and have your water tested.

bulletCan I test my water at home?

Do-it-yourself test kits are available for you to test your water at home.

However, these tests will never be as accurate as those performed in a state-certified lab.

For the best results, utilize the services of a certified lab in your area.

bulletHow often should I have my well tested?

The government generally recommends having your water tested annually for coliform bacteria and nitrates.

Other contaminants should be tested for once every five to ten years.

bulletHow long will it take to get the results?

It depends on the tests you’ve ordered.

For typical results, you may see your results as quickly as three to five business days.

However, some labs can take as long as two weeks to return your results.

bulletHow much property do you need if you require a well?

If your property has a well, then it may also have a septic system.

Because of this combination, you’ll want at least a half acre of land.

However, you will also want to check with your local planning department to see if they have additional lot size requirements.

For example, many New York towns require a minimum of two acres when a well and septic system are used.

This is because septic systems can leak and contaminate the well if they’re too close together.

bulletHow old is your well?

On average, a well typically lasts around 30 to 50 years.

If you’re purchasing a home with a well that’s over 20 years old, you should factor in replacing the parts of the well that will eventually fail into your budget.

For example, it’s common for well pumps to only last around 10 years or so.

Make sure you ask the owner how old the well is, and if they aren’t sure, get a well inspection.

Inspections often show some clear signs of age!

bulletWhat type of well is acceptable?

You should try to buy a home with a drilled well.

A drilled well typically goes down 100 feet or more and is built with special equipment.

A drilled well is preferred over a dug or bored well as they are more reliable and less prone to contaminatio

You can recognize a drilled well because there will be a pipe sticking up out of the ground at least a foot or more with a thick cap on the end of it.

bulletHow far apart should the well and the septic system be?

A well and the septic system should be at least 100 feet apart; however, every jurisdiction has slightly different regulations.

If you come across a home where the septic system and the well are close together, then it’s best to avoid buying this home.

bulletWhere should the well cap be?

A well cap should always be located uphill or on level ground.

As contaminants (like oil and grease from your driveway or manure from your livestock) fall on the ground, they can flow downhill and contaminate the well where water pools on the ground; thus, you always want your well to be located on a level surface or uphill so contaminants can’t accumulate on top of it.

9. What should I know before I get a well inspection?

You shouldn’t buy a home with a well without testing that well first.

Well testing will check for two things: water quality and water quantity.

For water quality, a water sample will be taken from the tap and sent to a qualified lab where tests are performed.

The lab will run the test analysis and return your results letting you know if you’ve passed the limit for each element.

In some cases, you may be told that your water is “unsafe.”

Check out #11 if you want to know why.

There’s an indefinite number of possibilities for why your water quality may be unsafe, and you should consider all of them as you address the problem.

For water quantity, most locations require that the well produces 3-5 gallons of water per minute.

Generally, you’ll see a 3-gallon minimum is required for older homes and a 5-gallon minimum for new homes.

It’s important to note that just because a well has clean and safe drinking water does not mean that it has a large enough quantity to meet the needs of your household.

When you get your well inspected, a professional inspector will help you check the flow rate.

If the test finds the well doesn’t have the capacity to handle your water needs, the most common fixes are:

bulletDrilling a new well

You can drill a new well in a different spot that has better access to water.

Just keep in mind that this will cost between $4,000-$15,000 depending on the soil and the depth of the water.

Keep in mind that if you decommission the existing well on your property, there are usually regulations governing the proper procedure.

Typically, the well will need to be professionally filled and sealed.

This way it does not drain, contaminate or otherwise harm the groundwater.


This method injects high-powered water into the rock formation around the well.

The idea is to widen the fractures in the rock to increase the network of water-bearing fissures that supply water to the well.

10. How much does well testing cost?

A full well inspection ranges from $250 to $550.

The ultimate cost will depend on the inspector and the type of water test they must conduct to check the water quality.

11. What is causing my water sample to test as “unsafe”?

Water contamination can be caused by a wide variety of reasons.

The following list details possible problems.

bulletPoor sampling technique

I.e. dirty hands, sample bottle cap set on ground or countertop, sample water poured from another container to sample bottle, water splashing off floor or bottom of sink while taking a water sample

Note: Bacteria testing is very sensitive, and you’ll want to make sure you’re careful, so there’s no cross-contamination.

bulletDirty sampling faucet

bulletLeaking or dirty swing tap

bulletPlastic parts on sampling faucet

If the faucet has a plastic throat, don’t use it!

bulletSample was taken through a faucet aerator

bulletFaucet not sterilized

bulletInsects in a frost-free hose bib

bulletSampled through a garden hose

Never take a sample from a hose!

bulletGarden hose water line was left under pressure

Bacteria love garden hoses and can move backward through a water system

bulletStagnant water in an unused well

If it hasn’t been used, flush the water prior to sampling

bulletBad pressure tank

bulletBuried pressure tank with a pinhole leak

bulletStandard pressure tank with contamination (bacteria) above the waterline

Always waterlog a standard tank when chlorinating a system

bulletBladder or diaphragm in the pressure tank leaking

bulletBladder in the captive air pressure tank fouled and the bacteria have turned anaerobic (septic)

bulletThe well hasn’t been cleaned in 20 years and just needs a good well cleaning (read the next section about well cleaning!)

bulletCrack in the well casing or a bad weld at a seam

bulletUnused, off-line water softener that is fouled

What a great place to grow bacteria

bulletWell casing too close to the ground

Keep them 12” high

Note: A lawnmower can blow dirt in the well

bulletBroken well cap causing insect/vermin problems

bulletNo well cap at all or a pail or coffee can over the well casing

bulletInsects in the well

Anything crawling across the ground can contaminate it!

bulletEarwigs in the well

The only way to clear earwigs is to “vacuum” and aggressively clean (chlorinate) the well

bulletBroken (leaking) lateral between the well and the house

bulletIron or sulfur bacteria that has built up a heavy biofilm which is hiding and growing coliform bacteria

bulletLeak at the pitless adapter

bulletPour grout job at the well casing or no annular space seal

You’ll see surface water running down along the outside of the well casing if this is an issue

bulletDepression at the well casing

Surface water will gather here and saturate the soil as it runs down next to the well casing

bulletWell casing has lifted with the frost and needs to be pounded back down

bulletNo backflow prevention device between the boiler (hot water heat) and the water system

bulletAn electrical problem in the well

A skinned wire can provide an environment to enhance bacteria growth

If you fix the electrical problem, then you’ll resolve the water issue

If you have “red” water coming out of the tap, then that’s another flag for an electrical problem in your well

bulletNo air gap at the dishwasher

bulletBuried suction line

Jet pump with no conduit or standard seal-cross fitting

bulletSample not taken at the sampling faucet

Sample the water as close to the well as possible!

bulletRain gutter downspout directed at the well casing

bulletSump pump discharge directed at the well casing

bulletWell housed in a non-complying well pit

bulletNo overflow for seasonally flowing well

bulletNo airgap at flowing well

Overflows discharge – bacteria, vermin, fish, etc. can swim up the discharge pipe into the well

bulletAn abandoned well in the vicinity of the present well

bulletA second, unused well on the property

bulletHome-made plumbing or plugs in the water system

bulletLaboratory error

Very rare!

And on the list goes!

There is a never-ending list of well problems, but this gives you an idea of what you could be working with.

If your water test is coming back as “unsafe,” be sure you exhausted all possibilities, and keep in mind that it’s unlikely that the laboratory got it wrong.

It’s more likely that you have an issue in or around your home that’s causing unsafe water.

12. Do I need a professional to clean my well, or can I clean it myself?

You can clean your well yourself with household chlorine bleach, garden hoses, leather gloves, five-gallon pails, and tools to remove your well cap.

It will require time and effort, and it will leave you without usable water for 8 to 30 hours.

You can read detailed instructions about Well Cleaning/Disinfecting Instructions here.

If you have any concerns about doing it yourself, call a professional to clean your well.

Final thoughts

Don’t skip out on the crucial home inspection tests!

Purchasing a home with well problems (i.e. one that has a well and septic system too close together) will cause you major issues down the road.

Well testing is part of your due diligence, and you won’t be sorry you did it.

Would you like to receive weekly emails with our latest blog/properties?

Subscribe Now

Erika Gokce Capital

Disclaimer: we are not lawyers, accountants or financial advisors and the information in this article is for informational purposes only. This article is based on our own research and experience and we do our best to keep it accurate and up-to-date, but it may contain errors. Please be sure to consult a legal or financial professional before making any investment decisions.


3 thoughts on “Well Testing: 12 Things (2024) You Need To Know”

  1. It’s look like dream come true 🤗

  2. VERY informative article. Brought up some things I never would have thought of. Thank you so much!

    • Thank you, Aubrey. I’m so glad our article was helpful!


Leave a Comment