Well Water: Contamination, Treatment, Purification & Filter Systems

What’s In My Home Well's Drinking Water?
Well, the obvious answer is…WATER! However, there’s more to it than that. People on the outskirts of cities, in small communities and in rural areas depend on wells for their drinking water. If your well is located and constructed correctly, it can be a source of good drinking water for decades. However, unlike water supplies in large municipal and urban centers, there are often no regulations pertaining to the quality of private water supplies like a well. Often times the only requirement for testing is in the event of a real estate transaction, for insurance purposes, or for other administrative reasons. Beyond this and unless there is unexplained illness, the majority of well owners never even think to test their well for water contaminants that could be present in every glass of water. Microbiological contaminants in well water, such as E.coli, Giardia, or Cryptosporidium, are invisible to the naked eye. Clear water from your well does not always mean safe water, so that's why you need to consider a UV systems to purify and filter your wells water before entering your home.

Well Water Contaminants
How Do Contaminants Get Into My Homes Well Water? Contamination of groundwater wells can occur from both above and below the surface. Heavy rainfall, spring runoff, or flooding events can overwhelm even well-constructed, newer wells, and introduce surface water (such as agricultural run-off) into the aquifer below. If you have an older well for your homes water, there is greater potential for contamination from surface water. Your well was likely constructed to less stringent requirements and may not include elements that have since been demonstrated to provide better protection such as a sanitary well cap, proper grout seals, or a well casing that extends above the surface. And with every passing year, there is more risk from structural deterioration. Your local well drilling professional can conduct a thorough assessment of your well and help you to minimize the risks of bacterial contamination in your drinking water.

Septic Tank System
Septic Tank System
The majority of homes using a private water supply will also be relying on a private waste-water (septic) system. According to the EPA, improperly used or maintained septic systems can be a significant source of ground water contamination that can lead to waterborne disease outbreaks. Make sure your septic system is checked annually and well-maintained to avoid contaminating your water.
Wells Aquifer
Wells Aquifer
Even if your own well is in good shape and not contaminating the aquifer nor your drinking water, you can’t be sure that is true of all wells connected to the same aquifer. Aquifers can be connected through fissures and cracks in the bedrock, and water can flow through from one to another, taking contaminants with it. Its best to proactively treat the water coming into your home to ensure any potential contamination is removed before the water is used.
Abandoned Well
Abandoned Well
In long-established rural areas, many generations have built homes and drilled wells over the years. Back in the day, there was no requirement to register wells when put into or taken out of service. Abandoned or improperly decommissioned wells can be a problem in many rural areas and are a significant conduit for surface water to infiltrate and contaminate aquifers and as a result, any wells currently in use.

Recommended For Well Water Treatment: Home UV System
Recommended Home UV Systems For Well Water Treatment
UV Systems for Small Homes
Small Home
Viqua Sterilight SC 200 has a 8 gpm flow rate, and is a compact sized UV system for treating well water for small homes.
» See Details
UV Systems for Medium Homes
Medium Home
Viqua Sterilight S12Q-PA has a 15 gpm flow rate, low maintenance system well water treatment system ideal for medium size homes.
» See Details
UV Systems for Large Homes
Large Home
Viqua Sterilight SC-600 has a flow rate of 32 gpm, a high-output UV lamp that is suited large homes and
» See Details

Browse Home UV Well Water Treatment Water Systems
For The Tap
For The Tap UV systems for point-of-use well water treatment, typically at a single tap or faucet. Plus systems offer additional features.
» Tap Water UV
» Tap Plus Water UV
For Your House
UV systems for point-of-entry or whole house well water treatment with multi water outlets. Plus systems offer additional features.
» Home UV Systems
» Home Plus UV Systems
Professional Systems
UV systems designed for point-of-entry well water treatment in larger homes. Plus systems offer additional features.
» Professional Systems
» Professional Plus Systems

Well Water Testing
How Do Contaminants Get Into My Homes Well Water? Have you ever been sick and weren’t sure why? Felt like you had the flu, or had stomach problems, or just felt awful? Sure. But sometimes, it’s not the flu – it’s the water. Unless you do a water test, you can’t know that your water isn’t going to make you or your family sick. Unfortunately, beyond the times when a water test is required like when selling your home, remarkably few well owners test their water annually as recommended by public health authorities. You can’t deal with a problem you aren’t aware is even there. Having your water tested can confirm any issues and allow you to take the necessary actions to protect yourself and your family. For your own peace of mind, water testing is a good idea. It’s also an important part of responsible well stewardship. Check your local regional health authority website, or other municipal resources, for local regulations, sampling procedures, water testing facilities (accredited testing labs) and any associated fees.
Well Water Testing
When Should You Be Worried About Your Well Water Test?
Most labs will have call-outs at the bottom of the test report that indicate if you should be concerned about a particular result. Use Table 1 as a guideline regarding Total Coliforms and determining if follow up actions are required.

According to a recent study in the US, as many as 19.5 million cases of illness every year can be attributed to contaminated drinking water.
(This information was found in the "Boil Water Advisories: What can you do?" article from Viqua.com.)

What Does My Well Water Test Numbers Mean? Your well water test results can be confusing but don’t have to be difficult to interpret. Presentation of results may vary by lab or locale. Regarding microbiological contamination, the most important measurement result is Total Coliform Bacteria (TC). Coliform bacteria occur naturally in soil and decaying vegetation. They are associated with the presence of human or animal fecal contamination. While many coliform organisms are completely harmless, some like E.coli, can make people sick and can even be deadly. E.coli is found in Giardia and Cryptosporidium are usually considered surface water issues and are not usually part of a well water test. However, this does not mean that they can’t or won’t be present in your well water. Both of these microbes live in the intestines of warm-blooded animals, and can be present wherever there is fecal contamination or surface water infiltration into a well or the intestines of warm-blooded animals like cattle, dogs, and humans. When a water test indicates a high “Total Coliform” count, it may or may not include illness-causing strains such as E.coli. BUT when present, coliforms are a strong indicator that your water source has already or can easily become contaminated with fecal matter.
Well Water Test Numbers

My Well Water Tested Positive For Bacteria. What Now?

Total Coliforms
0 or ND (not detected)
Your water is safe for drinking
Your water is safe for drinking if it tests negative for fecal coliform or E. coli.
6 or higher*
Your water is not safe for drinking unless you boil it.
Your water is not safe to drink unless you boil it. Sometimes, your test results will say “O/G” or “overgrown” instead of listing the number of total coliforms. This means there are so many other types of bacteria in your water sample, the lab technicians couldn’t see whether there were any coliform bacteria.
*If you see “est.” or “estimate” next to your test results, it means there were coliform bacteria in your water. However, because there were so many other bacteria as well, the lab technicians couldn’t accurately count the number of coliform bacteria. Your water is not safe to drink unless you boil it.

The first line of defense is to “shock” the well with a high dose of chlorine. Specific instructions detailing the amount of chlorine needed for the depth of your well, the pH of the water and the presence of slime or biofilm are available online. If you proceed yourself, keep in mind that chlorine is corrosive and should be handled with care. Leave the chlorine in the well for at least 12 hours and then purge the water. Highly chlorinated water is not safe to drink! Better yet, call in a water treatment professional. An expert will know exactly how to proceed and can also identify deficiencies in your well that may contribute to contamination. It’s important to remember that shocking your well doesn’t offer a long-term solution for ongoing contamination issues. It’s a quick fix that is best paired with long-term disinfection.

Generally Giardia and Cryptosporidium are considered surface water issues and are not part of a well water test. They can be present wherever there is fecal contamination or surface water infiltration into a well or aquifer.

Phew – glad that’s over with. Now I don’t have to worry, right?
If you’ve shocked your well, re-tested, and received a clear test, you would think you shouldn’t have to worry about it again. THINK AGAIN! If a well has been contaminated once, it means it can become contaminated again. Water quality is NOT static and changes throughout the year. Unless you are willing to restrict yourself to bottled water for cooking and drinking, which can be expensive and creates waste, you will want to consider continuous disinfection of your water supply.

Top 6 Causes - Outbreaks in Individual
(Private) Water Systems - Wells
Top Causes of Outbreaks in Wells According to The CDC.
  1. Hepatitis A
  2. Giardia
  3. Campylobacter, E. coli (tie)
  4. Shigella
  5. Cryptosporidium, Salmonella (tie)
  6. Arsenic, Gasoline, Nitrate, Phenol, Selenium (tie)
For a complete listing of water-related surveillance data, see The CDC's Surveillance Reports for Drinking Water-associated Disease & Outbreaks.

For More Information, Visit One of the Links Below

Well Water Information Based on Where You Live (United States Environmental Protection Agency)
State Certified Drinking Water Laboratories (United States Environmental Protection Agency)
Private Ground Water Wells (Centers for Disease Control and Prevention)
WellOwner.org (National Ground Water Association)

What Are Some Whole-House Well Water Filter & Treatment Options?

There are various approaches to disinfect your water, and a UV system for well water is a great Eco-friendly option. Additional considerations would be if you want to treat all your water as it enters the home (Point of Entry or POE), or if you want to have a disinfection system under your sink or on top of the counter (Point of Use or POU). A water treatment professional can help you determine which disinfection system is best suited to your water conditions and assess any need for pre-treatment (reducing hardness, ferric iron, etc.), which is very important for thorough disinfection.

Point-of-Entry and Point-of-Use System Definition
Which of the systems you need depends upon what you hope to accomplish with your filtration needs. What's the difference?

Point of Entry (POE) POE systems welcomes water into your entire home. Its purpose is to treat all of the incoming water before it goes into the individual supply lines that feed your laundry, toilets, bath, outside faucets, and sinks.

Point of Use (POU) POU systems provide filtered water only where you need it. Typically they are installed at a single water connection like under the counter of a kitchen or bathroom sink. These lower capacity, smaller systems will filter water at the actual "point" where it is being used.

Whole-House System If you are looking for a complete solution for drinking, cooking, and bathing water for your family, you should elect to install a Whole-House System.
A combination of both POU & POE systems, Whole-House treatment filters the water for your entire home.

Well Water Treatment Method: UV Systems
Well Water Treatment Method: Ultraviolet Light (UV) Systems
- Requires no chemicals
- No disinfection by-products
- Easy installation
- Effective against Cryptosporidium
- Does not alter the taste or odor of your water*
- Usually requires pre-treatment (e.g. softeners in hardwater areas)
- Some viruses require high UV dose
- Yearly lamp replacements
- Occasional quartz sleeve cleaning or replacement
Well Water Treatment Method: Chlorine
Well Water Treatment Method: Chlorine
- Reduces some disagreeable taste/odor
- Provides residual disinfection
- Can help remove iron/ manganese from water
- Requires storage/use of noxious chemicals
- Requires ongoing monitoring of chlorine levels
- Cryptosporidium and Giardia are highly resistant
- Often requires contact tank
- Requires professional installation
- Can alter taste/odor of water
- Corrosive
- Can produce harmful by-products
- Checking for loose, worn, missing, or broken parts
- Cleaning the entire system semi-annually
- Cleaning all surfaces showing corrosion
- Refilling chlorine supplies
- Cleaning any clogged injectors
Well Water Treatment Method: RO Systems
Well Treatment Method: Reverse Osmosis Systems

- Filters many contaminants from water
- No chemicals required
- Can produce 2–4 gallons of waste water for every gallon of treated water
- Can demineralize water
- Reduces pH
- Can require pre-treatment
- Often requires professional
- Water filter replacement
- RO Membrane replacement
*Most RO units are not specified to remove microbiological contaminants. Check the manufacturer’s specifications.
Well Water Treatment Method: Water Filters
Well Water Treatment Method: Water Filters

- Can remove some disagreeable tastes odors
Not a stand-alone solution
- Yearly lamp replacements
- Occasional quartz sleeve cleaning or replacement
*Filters can remove some large microbes, but do not thoroughly disinfect.
Well Water Treatment Method: Water Softener
Well Water Treatment Method: Water Softener Systems
Used as pre-treatment for hard water or other water treatment conditions
Requires a professional to install the system
Salt replacement as required