Home water filtration: Understanding the basics

Are you concerned about the taste and safety of your drinking water and therefore considering water filtration? Lots of people are, but that’s not new. What is new, however, are all the ways you can now improve your tap water with in-home technology.

The possibilities have improved lately, mostly because we’re worried. Is our water as safe as we once thought? Maybe, but lots of us aren’t entirely convinced. That’s where the water filtration steps you’ll find here can help.

Water filtration step #1: Find out what you’ve got

Many local governments provide access to basic, microbial water testing services through district health units, though the emphasis here is on the word “basic.” Government testing is typically for bacteriological contamination only, not chemical contamination.


While bacteriological insights certainly are useful, a sample of, say, sterile water laced with arsenic would still get a potable rating according to these simple tests. Yes, bacteria can hurt you, but most of the public anxiety about drinking water these days springs from possible chemical contaminants, doesn’t it? The knowledge most of us have of chemical hazards is incomplete, so we’re especially nervous.

water filtration steve maxwell faucet running water
Water filtration is often a part of providing an optimal source of water for your family. Photo courtesy Steve Maxwell

More complete testing for a range of substances is available through private labs, with costs ranging from $50 to $400 per test. Google the name of the area where you live, plus “water testing” and you’ll find the most important local testing options. But even then, such tests will only provide a snapshot of current water purity. Water quality will change over time, and old test results can’t necessarily warn you of new dangers.

If you have reasons to be concerned about your drinking water now, how long will a safe test result ease your mind? Drinking water analysis is useful but, for most of us, it isn’t the complete answer to our concerns, even when the results are apparently reassuring.


Water filtration step #2: Protect against chemical contaminants

If you’re connected to a large municipal water supply, your primary concern is probably about chemical contaminants, not micro-organisms. Sure, microbes can and do get into municipal water, but the systems that deliver safe water are designed to eliminate these critters at source and, by-and-large, constant monitoring and public announcements will usually keep you informed if micro-organisms enter your municipal supply.

Ironically, chlorine is the tool most often used to purify water municipally, and chlorine is now one of the leading causes of health concerns (and taste concerns) among the discerning water-drinking public. Just consider the popularity of carbon filter jugs and you’ll see what I mean. In fact, chlorine has become a real source for concern, and for good reason.

A growing list of scientific findings suggests that when chlorine reacts with organic substances (such as bacteria) in water, it produces a family of chemical by-products called trihalomethanes. Water drawn from surface sources, such as lakes and rivers, is most likely to contain organic substances. In high enough concentrations, trihalomethanes have been linked to serious health problems.


At first these studies were easy to ignore, but as similar findings arise from more and more studies, it’s getting difficult to dismiss them. Even the steam from chlorinated showers has received scientific scrutiny as a source of inhalable trihalomethanes that are even greater than those ingested from drinking water.

Water filtration step #3: Choose your equipment

Whole house carbon filter

This option is for eliminating (or greatly reducing) chemical contamination of your water, and the presence of chlorine and fluoride. A whole-house carbon filter is also one of the easiest ways to get rid of those by-products of chlorine — namely trihalomethanes — that affect the safety of showers and bathing.

water filtration steve maxwell carbon filter
This is a whole-house carbon filter. Granulated carbon is stored inside. As water flows through this carbon, chemical impurities, odours and tastes are removed very effectively. Photo courtesy Steve Maxwell

The filter above is what I have at my place. Whole-house units like these can be installed to treat all the water you use for about $1,500. The granulated carbon inside the filter needs to be replaced every two to three years at a cost of $150 to $200.


Carbon derived from coconut shells is regarded as the most effective type for water filtration purposes, but even with this premium stuff on your side, you won’t necessarily get rid of dissolved substances such as sulphur that lead to a rotten egg smell. More on this later.

The carbon filter you see in the photo above is large and effective. It requires automatic backwashing every few months to stay effective. You can set units like this to backwash on a schedule automatically.

At-tap water filtration

If your aim is the most chemically pure drinking water you can get from a given water tap, you’ve got two main options: distillation and reverse-osmosis filtration. Neither of these choices are practical for whole-house applications because of their low daily outputs. Both are designed to treat only one or two taps in a house.


Distillation systems ($500 to $3,000 plus installation costs) use electricity to boil then condense water to purify it. Everything is removed by this process, except volatile chemical components that boil and condense along with the water. You’ll need to add a carbon filter to get rid of these.

Distillation plus a carbon filter is a practical way to get absolutely pure drinking water. This is the system we use at our place and I’ve found that drinking distilled water is an excellent health booster in several ways.

Reverse-osmosis (RO) systems ($1,000 and up), use a very, very fine filter membrane to remove everything that’s not water. Even substances held in solution are removed by this process. Moderately hard water will clog up a reverse-osmosis system quickly, though, as will any kind of sediment, however small.


For this reason, RO systems often come bundled with other filter components that keep things working. You may also have to add a water softener to your household water system if your water is hard. Maintenance of an RO unit involves changing the membrane every few years at a cost of about $200.

Whole-house microbe control

If you draw water from a well, lake or river, or you get it from a questionable municipal supply, you may have legitimate concerns about micro-organisms in the water that comes out of all your taps. Send in samples and find out what’s happening. The most vulnerable time of year is spring and fall, when rainwater sloshes down freely into the underground aquifer.

Home-based options for microbial treatment include small chlorination or iodination units and ultraviolet systems that kill critters with light. Chlorination, iodination and ultraviolet systems can treat all the water that flows through your house.

steve maxwell h2o2 pump hydrogen peroxide
This injection pump puts 35 per cent hydrogen peroxide in drinking water as it comes from a well. It’s energized every time the water pump switches ON. Photo courtesy Steve Maxwell.

Hydrogen peroxide injection is one way to treat water for bacteria and odours. I’ve lived with this system in my own house for more than 20 years and I like it a lot. Besides killing germs, hydrogen peroxide (which is just an ordinary water molecule with an additional oxygen atom tacked on) also has the effect of transforming odour and taste-producing components into forms that can be filtered out easily.

Sulphur water, a condition that makes some well water smell like rotten eggs, can be effectively treated with a hydrogen peroxide/carbon filter combination. This is one of the only options for effectively eliminating the smell of sulphur water.

The largest municipal use of hydrogen peroxide technology for odour control of sulphur water began several years ago in southern California. Various oxygen-based systems (such as ozone treatments) are used in about 60 per cent of European municipal water supplies. The drawbacks of chlorination have been a public concern for a long time in that part of the world. Take a video tour of the hydrogen peroxide water system I run at my house.


Got a water well?

There’s a lot more to getting great water from a well than when treating a municipal supply.

  • Got a weak well that doesn’t provide enough water? There’s a fix for that (and it really works).
  • Want to save big money installing and maintaining your own water pump and pressure tank?
  • Got a failing septic system that looks like it might need an expensive replacement? Chance are there’s a much easier (and less expensive) way to get things going again without replacement.

I cover all these things and more in two of my most popular online courses. Want to learn about maintaining and troubleshooting your water well and septic system without expensive, professional help? Check below for the two in-depth courses I offer on this — 100 per cent satisfaction or your money back, so there’s no risk.

Course #1: Reliable water from your well: Build a safe water system and maintain the flow.


Course #2: Septic system Rescue: Revive your own septic and restore performance.

About the Author

Steve Maxwell

Steve Maxwell

Steve Maxwell has been helping Canadians with home improvement, gardening and hands-on living since 1988. Visit for videos, stories and inspiration.



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