Your car isn’t the only problem. Your taps are driving more carbon than you think.

Most of us think we’ve got a decent handle on our carbon footprint. We think about flights, we think about what we eat, and we definitely think about our cars. Water, on the other hand, barely registers. It’s just there, part of the background, doing its job.

That assumption turns out to be wrong.

What people believe vs what’s actually true

We asked Brits a simple question: what emits more carbon – your car, or the water you use every day at home?

Nearly three quarters, 73%, picked the car.¹

It’s an understandable answer, and it’s also often incorrect.

In reality, a typical four-person household’s annual water use produces around 1.5 times more CO₂e ² than a family petrol car driving the UK average of 7,600 miles³ a year. In other words, the emissions you never think about are quietly outpacing the ones you do.

Why water isn’t as “clean” as it feels

Water feels neutral because we only ever see the final step, the clean water coming out of the tap. What we don’t see is everything that had to happen before that moment, and everything that happens after.

Every litre has to be extracted, treated to drinking standards, and pumped through miles of infrastructure before it even reaches your home. Then we heat a significant portion of it for showers, washing and cleaning, which is where a large share of the carbon comes from. Finally, it’s treated again once it disappears down the drain.

That entire system runs on energy, and energy still largely means carbon.

So while water looks simple, the system behind it is anything but.

The real problem: water is invisible

This gap in understanding isn’t surprising when you think about how we experience water. You can see fuel going into your car. You can see the price of electricity ticking up on a bill. Water, by contrast, is mostly invisible.

Leaks hide behind walls. Heating happens inside boilers. The infrastructure sits underground, out of sight and out of mind.

And when something is invisible, we tend to underestimate both its impact and its cost.

The UK’s water reality is catching up with us

At the same time, the bigger picture is shifting.

The UK will need an additional 5 billion litres of water every day by 2050⁴, which is close to twice what London currently uses on a daily basis. That’s not a distant, abstract problem. It’s a supply challenge that’s already forming while demand continues to rise.

Yet we still behave as if water is effectively unlimited, because culturally, that’s how it’s always been framed.

What actually moves the needle

The encouraging part is that reducing water use has a direct and immediate effect. Cut water, and you cut the energy needed to move and heat it, which means you cut carbon as well.

In practice, that can be surprisingly simple. Shorter showers, fixing leaks early, and paying attention to how much hot water you’re using all make a measurable difference. In higher-use households, the potential savings are significant, both in terms of emissions and cost.

We’ve seen cases where daily consumption drops by hundreds of litres once people can actually see what’s happening. Awareness changes behaviour, and behaviour changes outcomes.

The shift that hasn’t happened yet

We’ve already gone through this learning curve with energy. We installed meters, built dashboards, and started tracking usage in real time. That visibility changed how people think and act.

Water hasn’t had that moment yet.

It’s still treated as background infrastructure instead of something to actively manage. But the data is clear: it carries a real carbon cost, and that cost is only becoming harder to ignore.

Right now, most buildings are flying blind.

And when you can’t see it, you can’t fix it.

¹ Independent market research company Censuswide was commissioned by Watergate to conduct a nationally representative poll of 2.000 British adults in August 2024. See data here.
² CO₂e stands for Carbon Dioxide Equivalent, which is a unit of measurement that compares the impact of greenhouse gases (GHGs) on the climate.
³ The water consumed by a typical UK household emits 2.6 tonnes of carbon a year – one and half times more than a typical car driving the UK annual average of 7,600 miles which generates 1.749 tonnes per year. Data from CCW shows each person uses 145L of water per day, which is equal to 211.7 cubic metres annually in a four-person house. The CCW also says 109L of water is leaked per property per day (39.785 cubic metres annually), giving total consumption of 251.485 cubic metres/year. Every cubic metre of water we use generates a carbon footprint of 10.4kg of CO₂e, as per data from sustainability experts, Dar, 
⁴ London consumes 2.6bn litres of water per day, Source: Greater London Authority.