Since we’re in the business of water filters, we often get asked some variation of the question posited in the title: “Why isn’t tap water ok?”, “Why should I filter my water?”, “What’s so bad about drinking unfiltered water anyway?”

Water filters have become the gold standard in home water treatment solutions and their increasing popularity is contributing to the steady decrease of bottled water consumption both in UK homes and offices.

But with great popularity comes increased scrutiny, and some still question whether water filtration is absolutely necessary, especially considering that UK water suppliers already treat municipal water supplies.

If you’re still wondering whether you should filter your tap water or continue drinking unfiltered water, this article will provide answers to your burning questions about water filtration.

What is Unfiltered Water?

Filtering water means passing it through a filter medium (which can be anything such as sand, gravel, a semipermeable membrane, an absorbing medium, etc.) that allows water molecules to pass through, but traps, absorbs or rejects water ingredients that are undesirable in drinking water.

These undesirable ingredients are referred to as contaminants, which can cause illnesses and health problems if they’re left in drinking water and they’re subsequently consumed by drinking water that contains them.

Municipal water treatment already puts water through a large-scale filtration process by using sand and/or gravel of various dimensions, plus it also disinfects water by using a disinfection agent (chlorine or chloramine) to kill off pathogenic bacteria.

Therefore, strictly speaking, tap water isn’t unfiltered. Water that you would source from a spring or stream and consume it “as is” would better fit the “unfiltered” description.

While you can drink tap water as it comes out from your tap, drinking water sourced from an untested and untreated source (e.g. a private well) is not only inadvisable but also dangerous.

While water is highly nourishing and indispensable for our survival, it’s also very good at picking up trace amounts of contaminants and transporting them with it.

Water can carry viruses, bacteria, cysts, and other disease-causing pathogens along with many other unwanted water ingredients such as heavy metals, pesticides, herbicides, industrial solvents, and so on.

Municipal water treatment is great at dealing with most of these issues, however, water can still pick up contaminants on its way from the treatment sites to your home.

Therefore, municipal water treatment should be viewed only as a first line of defence against water contamination.

When it comes to unfiltered “raw water” such as the water sourced from a private well, the situation is different.

While drinking tap water won’t cause an immediate danger to your health, drinking water from a well is problematic at the very least.

Since these sources haven’t been put through any treatment or filtration process, water filtration is indispensable in these cases.


The Case for Filtering Water

There are many reasons why you should consider filtering your tap water and why you should add that extra layer of protection on top of municipal water treatment.

So, here’s why you shouldn’t drink unfiltered water and why filtering your tap water is a good idea regardless of whether it’s coming from the municipal water supply or from a private well:


Water is a universal solvent that can pick up contaminants even after it’s been treated by your water supplier

Whether it’s sediments, rust particles, copper or other metal that gets into your water as a result of corrosion, once water gets out of the treatment process and it’s distributed, your water supplier will no longer monitor it while it’s in transit to your home.


The water treatment process itself adds undesirable contaminants to water

Chlorination is currently the easiest and most affordable way of killing off disease-causing pathogens in water.

While chlorine levels are closely monitored, some at-risk categories might still want to take measures to remove chlorine from their water supply.

People with asthma, people with skin conditions that are made worse by chlorine as well as people with small children may want to avoid any contact with chlorinated water.

Filters that can help in chlorine removal:



Despite municipal water treatment taste and odour issues can persist

Even if municipal water treatment does an excellent job at removing contaminants, taste and odour issues can still make your tap water unpalatable.

To remove strange flavours and odours from your drinking water, you can install taste and odour filters at your kitchen sink.


At-home water filtration significantly reduces the need for bottled water

Once you have contaminant-free and great-tasting water flowing from the tap, you will no longer need to bother with bottled water.

While this is convenient and significantly reduces your costs, it’s also a great thing for the environment — it reduces plastic pollution and your carbon footprint.


Water filters are affordable and easy to service

Water filters cost less than always relying on bottled water, plus, once they’re installed, they’re so easy to maintain that anyone can do it.

Filter changes are the only thing you’ll need to take care about and even that you’ll have to do no more than 2-3 times a year.


Finding the Right Filter for You

So, you’re on board with the idea of installing a water filter, but a quick glance at any water filter shop in the UK or elsewhere, and you’ll soon be scratching your head.

There may be a lot of filter types and brands, but at the end of the day, there are only two major categories that you should be focusing on:


  • Point-of-use filters (e.g. under-counter filters or on-the-counter filters);
  • Point-of-entry filters (e.g. whole house filters).


Point-of-use filters are installed at a single water outlet in your home, which is usually the kitchen tap. Point-of-entry filters filter your entire water supply before it gets distributed in your entire home.

It’s very easy to choose between the two. Simply ask yourself: “Do I want filtered water for drinking purposes only? Or do I also want filtered water for bathing and washing too?”

If it’s drinking water filtration you’re after, go with a point-of-use filter. If you also want to bathe and wash your clothes in filtered water, then you should go with a whole house filter.

Regardless of which type you decide on, here are some further tips in choosing the best filter system for you:


  • Know your contaminants!

It’s hard to find a suitable filter without knowing what’s in your water. A laboratory analysis or an at-home testing kit will help you find out the type and level of contaminants in your tap water.

Water filters contain filter media that are designed to remove these contaminants, but not all filter systems are built the same.

Choose one that can tackle the exact issues you’re having with your water supply.


  • Opt for filters with multiple filter media inside

Water filters can have a single type of filter medium (e.g. activated carbon) or multiple types (e.g. reverse osmosis membrane and activated carbon).

Generally, the more types of filter media, the more complex the filtration. Therefore, choose multi-media filter systems for better filtration outcomes.


  • Look for well-established brands that have been around in the business for quite a while

Picking the brand of filter can also be difficult since they are so many. Research brands and look for a long-standing presence in the business.

Opt for standard housings and filter sizes, so you can upgrade your system as newer and better filter cartridges are released by manufacturers.


  • Check maintenance requirements and costs

The initial purchase costs of a filter may be low, but maintenance, i.e. replacing filter cartridges, can be costly. Therefore, you should check the yearly costs of replacing filters in your filter system.

In a nutshell, these are the main points you should consider when choosing a filter. Other aspects that are also important is finding a filter with a daily filtered water output that meets your daily water consumption needs as well as aspects related to ease of installation.

Once you find the filter that’s most suitable for you and you start using it, you’ll be happy you’ve decided to stop drinking bottled water or unfiltered tap water.


Water Filtering vs Water Softening

There’s an important distinction that must be made between water filtration and water softening. Water filtration removes contaminants from water making it safer for consumption, water softening exchanges hardness causing minerals for sodium.

Therefore, if you have a water softening system installed in your home, it won’t protect you from water contamination issues, and vice versa, if you have a filter system in your home, it won’t soften your water.

Water filters with scale-inhibitors will prevent scale formation, but it won’t deal with other issues caused by hard water.

A further distinction that is equally important is that water filters are designed to improve drinking water, while water softeners are designed to protect appliances in your home (e.g. washing machine, water heater, etc.).


Now that you know why you shouldn’t drink unfiltered water and how to choose a suitable filter for your home, you can improve the quality of your tap water, reduce your bottled water consumption, and save some money in the process.