Is bottled water better than tap water?

Around 70% of us in the UK buy bottled water, even if it’s an occasional choice for some. Most of us think we need to drink more water than we currently do to boost our health and hydration. Around 40% of bottled water consumers believe it’s healthier than other drinks. But what about tap water? Even though more people are now working from home and those on the move carry reusable water bottles, bottled water sales are still increasing. This suggests that not everyone is happy to drink water straight from the tap. So, is bottled water better than tap water? We take a look at all of the evidence.

How much-bottled water does the UK drink?

It’s estimated that people in the UK drank around 10 million bottles of water a day during 2021 - about 3.5 billion litres. We spent over £1.6 billion on bottles, mostly made of plastic. Less than 5% were glass. If we continue on the current trajectory, research suggests we could consume an extra 280 million bottles over the next four years.

One report says the UK population buys 7.7 billion single-use plastic water bottles a year. 91% of plastic water bottles aren’t recycled, and around 1,500 plastic bottles are thrown away every second. Sixty million plastic bottles end up in landfill every day.

By 2020, the UK produced 99kg of plastic waste per person per year. That’s the second highest in the world, after the US, which produces 105kg per person per year. England missed its national recycling target to recycle 50% of household waste by 2020. But the current economics of recycling don’t add up. It costs more to recycle a plastic bottle than to produce a new one and dispose of the old one. Also, it takes about 5.3 litres of water to produce a typical 500ml single-use water bottle in the first place. That’s ten times the amount of water it will ultimately hold.

We are all aware of the plastic pollution crisis, yet we are buying more single-use plastic bottled water daily.

What is mineral water?

Many people believe bottled water is better than tap water, and plastic bottled water bought on the go is super convenient when you’re not near a tap. The UK's most popular bottled water brands are Volvic, Evian and Highland Spring. Volvic and Evian are mineral waters. As its name suggests, mineral water contains many naturally occurring minerals found in groundwater that are essential for our health, but our bodies can’t independently create, such as calcium, potassium, magnesium, sodium, fluoride, iron, and zinc.

Mineral water must, by law, be directly pulled from a named, naturally occurring underground mineral spring that’s constantly flowing. Its original purity needs to be maintained, and its composition, which should be on the label, must remain stable over time. Mineral water must be bottled at the source, free of contaminants, and not chemically treated. The local authority should officially recognise it.

What is spring water?

Spring water is an alternative to bottled mineral water, Highland Spring being the UK’s most popular brand.Spring water should come from a named underground source and be free of any contaminants. It must be bottled at the source; therefore, it can’t be chemically treated through any community water system.

Spring water isn’t subject to as many regulations as mineral water in the UK, so while it still may contain as many minerals, it might have more or less. There’s no legal obligation to tell us what spring water constitutes.

Many spring water sources may be the same as our mains water sources, so we could be paying to buy the same stuff that comes out of our tap, minus the chlorine and other contaminants it might pick up.

Find out about all of the different types of drinking water

Where does tap water come from?

The water from our taps in the UK starts as rain. That rain either flows into rivers and streams, is collected in reservoirs or is filtered underground. Most of the UK’s tap water comes from surface water. This is water from natural rivers and lakes as well as human-made reservoirs.

Groundwater is found in the fractures and spaces between geological formations of rocks, sand and soil underground. These formations are called aquifers. Groundwater is stored in aquifers or moves slowly through them, effectively filtering it.

64% of England’s drinking water comes from surface water, compared to 80% of Scotland’s and nearly 93% of Wales’ water. Most of the rest comes from groundwater. According to the latest report from the Drinking Water Inspectorate (DWI) , 6% of England’s drinking water (and just under 1% of Wales’) comes from ‘mixed sources’. The DWI does not specify what these sources are.

Find out more about where our tap water comes from

How does tap water get treated?

Untreated surface water and groundwater is pumped to water treatment plants around the UK. Currently, 1297 different water treatment works across England, Wales, and Scotland are responsible for providing us with drinking water. Their types of treatment will vary according to where they’ve sourced water from.

Water is screened to remove large floating items, while heavier contaminants fall to the bottom of reservoirs, saving the need to remove them manually. Some waterworks use flocculation to remove smaller contaminants. A chemical coagulant is added to water, which causes small particles to bond, making them easier to remove.

Some small contaminants are trapped by passing water through rapid gravity filters - tanks of coarse sand. Slow sand filters then remove even smaller particles. Some waterworks create chemical reactions in water to remove microscopic and dissolved particles via ozone, carbon and ion exchange processes.

Finally, chlorine is added to disinfect the water from organisms and bacteria. This keeps it safe from reinfection while stored in covered reservoirs before being sent to our taps through a network of pipes and pumping stations. This journey may be over a hundred miles long. As chlorine evaporates from water over time, there may be more chlorine in our tap water if we live near a water treatment plant. Chlorine levels in our tap water may also vary between treatment plants, depending on the required amount of disinfection.

What’s in tap water?

Some of us may be able to taste and smell the chlorine that water treatment works disinfect our tap water with. We may also find our tap water has a bitter or salty taste and contains lots of little floating white bits. Along with scale depositing itself around taps, kettles and glassware, this is a sign of a hard water area. Hard water has a large amount of minerals dissolved in it. While these minerals are natural and have health benefits, having lots of them in your drink may put you off its taste and cause damage to your plumbing and appliances.

Find out where the UK’s hard water areas are

We may find lead in our tap water after it leaves the water treatment works, as it can come from old pipes in our home plumbing. Lead can be harmful if allowed to build up in our bodies and is one of the  World Health Organization’s (WHO) top ten chemicals of major public health concern.

Read more about the contaminants found in tap water

All these possible contaminants may be why many believe bottled water is better than tap water.

How long can you store tap water?

Many of us buy single-use plastic bottled water because we’re on the go or fill a reusable water bottle to carry with us. But for how long does this stored water remain safe to drink? According to Water UK , we can store tap water in the fridge for around 24 hours, during which it’ll be safe to drink. It’s best stored in a sealed glass bottle to prevent any contamination. After 24 hours, any added chlorine will likely have evaporated, and bacteria may begin to grow.

We should store water in sealed containers as it’s a universal solvent, meaning it dissolves more substances than any other liquid. Glass containers are best as they won’t affect the water. Stainless steel is a good alternative as it’s non-corrosive and doesn’t leach chemicals. Plastic is slightly permeable and can contaminate the water with the potentially harmful chemical BPA over time.

How long can bottled water be stored?
While bottled water manufacturers have to employ strict bottling methods to ensure their products last while on the shelves, water in plastic bottles should come with an expiry date. This expiry date, usually one to two years after manufacture, relates to the plastic packaging. Plastic releases chemicals into water over time, which will slowly accumulate in our bodies if we regularly drink bottled water.

As bought bottled mineral or spring water shouldn’t contain any chlorine, once opened, bacteria will begin to grow. Bacteria growth will be far less if the water is refrigerated. Once opened, shop-bought bottled water is best drunk within a few hours - especially if kept at room temperature.

Read more about how long water can be stored

Are there microplastics in bottled water?

Scientists believe we should avoid plastic bottles after mounting evidence that microplastics are ending up in human tissue . Plastic bottles can release debris, particularly when exposed to sunlight, which we then drink. ‘We should not drink bottled water in plastic bottles,’ one scientist has said. The study's author warned against microplastics, saying, 'a typical person ingests a credit card’s worth of them every week.’

Another study found double the usual amount of microplastics in the digestive systems of those who drank lots of bottled water. Microplastics were also found in the blood of 80% of people tested in a separate study . Half of those blood samples contained PET, which most single-use plastic drinks bottles are made from.

One of the UK authors of the most recent World Health Organisation report on microplastics in drinking water said bottled water can contain ‘a few hundred’ pieces of microplastic. Tests revealed that 93% of bottled water shows 'some sign of microplastic contamination.'

Is tap water better than bottled water, after all?

Considering this new evidence that leads scientists to warn us against drinking water from plastic bottles and the damage done to the environment from the continued production and disposal of single-use plastic, is tap water better than bottled water after all?

While the levels of most tap water contaminants are usually low enough not to present a serious risk to our health, most of the water companies across England and Wales have recently exceeded the acceptable levels of risk set by the water regulators. Testament from the Drinking Water Inspectorate says tap water contaminants continue to evade treatment by the water authorities. Continual failures on the part of the water companies do not help public confidence.

The most recent report by the DWI recorded 433 events across England during 2021 that posed a risk to public health. They said: ‘There have been events at key water treatment works, involving the use of unapproved materials in contact with drinking water, and issues around infrastructure resilience.’

The DWI made 92 recommendations to improve the safety of our drinking water. They said this ‘unusually large number of recommendations’ was down to ‘Inadequate risk management within company water safety plans… company policy and procedures, reservoir and network operations, and inadequate company investigations.’

The DWI themselves say we should filter our tap water. They recommend we take the following actions:

●Only drink freshly drawn water from the cold water tap directly off the water mains, usually the cold tap in your kitchen.

●If you haven’t run any water for several hours, fill a washing-up bowl before drinking any tap water. Don’t drink water which may have been standing for a long time in your pipes.

●Don’t drink or use the water from your bathroom taps for cooking, as it usually comes from a storage tank in the loft, so it won’t be as fresh as from your kitchen tap.

The DWI also says that there can be variations in the amount of chlorine present in different water supplies. So if you don’t like the taste or smell of chlorine, they recommend the following:

●Refrigerate your tap water in a sealed jug before drinking, but throw it away after 24 hours and clean the jug regularly.

●Use a water filter with activated carbon, which will remove the chlorine.

While tap water contaminants continue evading treatment by the water authorities, the onus is on us to put our own safety measures in place.

What’s the best way to filter tap water?

There are concerns about both bottled water and tap water. However, there is a solution that enables us to easily access healthy water on tap that tastes just as good as bottled water.

Virgin Pure’s latest home water system features the most sophisticated countertop filtration technology to deal with all tap water contaminants mentioned in this article, from chlorine to lead. Take a look at how we compare to other filtration solutions , such as filter jugs.