Bottled Vs Tap Water: Preferences And Impact
In general, bottled water and tap water are both safe to drink. In the US, the FDA regulates bottled water, while the EPA regulates tap water. The two types of water meet different standards of safety that each regulatory agency has decided as being appropriate. However, people prefer one over the other for “taste” or convenience reasons.
At the end of the day, it’s not hard to imagine that bottled water takes more energy to manufacture and at the end-of-use generates an extra “bottle footprint” that goes into landfills. For our readers, we also calculate that each bottle of water leads to carbon emissions of 300-500 g CO2. But let’s take a closer look at the calculus of bottle vs tap, energy and non-energy factors.
Bottled Water Versus Tap Water Facts
Carbon impact of a bottle of water vs tap water is much higher
Of greatest interest to ShrinkthatFootprint is the carbon impact of water. In a study by Gleick and Cooley (source: Gleick and Cooley 2009 Environ Res Lett), two scientists from the Pacific Institute in California estimated on the basis of energy inputs that the carbon production cost of a bottle of water was 5.6 to 10.2 MJ / liter (1.6 to 2.8 kWh / liter).
Here MJ stands for megajoules which is different from the unit of energy we use on this site (kWh – kilowatt hour). In contrast, the same authors estimated that producing the tap water equivalent would require 0.005 MJ (0.0014 kWh). The difference is about 1000 times less. If we just assume the lower-end estimate of 5.6 MJ, the bottle production part is 4 MJ. Therefore, 70% of the production cost of bottled water comes from the bottle itself.
Any energy use results in carbon emissions. To calculate the carbon emissions in the production of a bottle, first let’s create a conversion factor using the global average of 190 g CO2 per kWh of electricity used. This is the average CO2 emissions from using 1 kWh of electricity. The leads us to conclude each bottle of water generates 300-500 g CO2. In contrast, tap water would generate only 1/1000 of that, at 0.3 to 0.5 g CO2 for the same volume of water.
Global consumption figures are in the range of tens of billions of gallons of bottled water per year. Conservatively lets say that represents 10 billion bottles, or a little more than 1 bottles per person per year which seems reasonable. Then the total impact of bottled water on the planet is 3000-5000 billion g CO2 or about 3-5 million tons CO2 per year.
Fractionally it’s a small figure of the total carbon emissions globally, estimated in 2020 to be around 31.5 Gt or 31.5 billion tons. It’s about 1/10,000 or one ten thousandth of the total carbon emissions. As a raw figure, it’s still a pretty big number.
In summary, the carbon impact of a single bottle of water is at least 300 g CO2 per bottle.
Environmental impact of a bottle is worse
Bottled water has become increasingly popular in recent years, but many people are unaware of the environmental impact of this trend. Bottled water requires significantly more energy and resources to produce than tap water. Additionally, approximately 80% of all plastic bottles end up in landfills, where they can take hundreds of years to decompose. This not only creates mountains of waste but also releases harmful chemicals into the environment.
Therefore there are two ways bottled water is detrimental for carbon reduction. First, the fact that a thousand times the energy is needed to process and product a given volume of water means the carbon impact is a thousand times as large in production. Second, the fact that the bottle will decompose in a landfill means an increase in landfill emissions.
The saving grace here is that if the plastic is long lasting, then that decay is slow and there’s more time for landfills to implement emission gas capture technology. Furthermore, any toxins released from decomposing bottles can harm human health. The next time you reach for a bottle of water, remember the hidden cost of this convenience.
Cost of bottled water is higher
Bottled water is a big business, with the global bottled water market expected to reach $319 billion by 2025. But is bottled water really worth the cost? Let’s take a closer look at the facts.
On average, people in the United States spend about $1.22 per gallon on bottled water, while a gallon of tap water costs less than a penny. Bottled water is also much more environmentally damaging than tap water. It takes 2,000 times as much energy to produce a bottle of water as it does to simply fill it with tap water. In addition, only about 20% of plastic bottles are recycled, meaning that the vast majority end up in landfills or oceans.
Tap water is cheaper and more environmentally friendly than bottled water and regulated by the Environmental Protection Agency (EPA). This means that it must meet strict safety standards for contaminants. In contrast, bottled water companies are only required to self-report their compliance with food safety standards the Food and Drug Administration (FDA) set. Given all of these factors, it’s not clear that bottled water is worth the cost. Tap water is not only a better value, but it’s also a safer and more sustainable choice.
Regulatory bodies for the two are different
The difference between bottled water and tap water is regulatory too. In the United States, the FDA is responsible for regulating bottled water. Bottled water must meet the FDA’s Bottled Water Standards. The FDA has established two types of bottled water standards: Primary and Secondary. Bottled water that fails to meet the Primary or Secondary Standards are considered contaminated and must be removed from the market.
The FDA has also established bottled water regulations to protect consumers from false or misleading labeling.
For example, bottled water labeled “spring water” must come from a spring. In addition, all bottled water labels must list the product’s place of origin and any treatment the water has undergone. Bottled water that contains fluoride must also list the fluoride content on the label.
The FDA regulates bottled water in the same way it regulates other food products. The FDA inspects Bottled Water facilities and conducts scientific research on Bottled Water safety and quality. The FDA also works with state and local governments to enforce Bottled Water regulations.
Health And Safety – Flint, Michigan And Jackson, Mississippi Water Crises
Most people are aware of the dangers of consuming contaminated water. One of the highest profile stories about an unhealthy water supply is Flint Michigan which came about from the city switching the water source to the Flint River. A series of missteps and mismanagement led to very poor water quality. Residents generated data to show that there were high levels of contaminants in the water and children exhibited two to three times higher lead levels than before. Eventually the situation spiraled into the Flint Michigan water crisis, a truly tragic situation. These high profile stories about poor municipal water quality no doubt cause consumers to switch to bottled water, believing it is a safer option.
Another very high profile event was the flooding and subsequent disabling of the water treatment systems for the city of Jackson, Mississippi. The city of 150,000 was already dealing with a mini-crisis due to failing pumps and reliance on back-up pumps. The flood overwhelmed the system and put it in a situation where it was unable to provide potable water for an extended time.
However, these are one-off events. And given the lack of bigger studies and data, we would have to default to the position of saying its inconclusive whether bottled water is safer than municipal water.
Test Your Tap Water
One thing that we haven’t factored in is the “last mile” in connecting the municipal water supply to your home. The pipes in the home aren’t regulated by any agency. So it’s important to test your pipes in older homes.
Look up or contact the water treatment agency for your water source. They will have information about local testing companies or they will carry out tests themselves. The testing body will give you instructions on collecting water, usually in bottles, that you then mail to the testing body. They will carry out a battery of tests including lead contamination. A clean bill means your “last mile” is good and you should be ok with using the tap water.
In conclusion, bottled water is costly on the wallet, costly in terms of production emissions, and costly in terms of landfill emissions. If you’re looking for a safe and sustainable option, stick with tap water.