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From space, our planet appears to be more ocean than earth.
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But despite the water covering 71% of the planet's surface, more than half the world's population endures extreme water scarcity for at least one month a year.
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And current estimates predict that by 2040, up to 20 more countries could be experiencing water shortages.
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Taken together, these bleak statistics raise a startling question: are we running out of clean water?
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Well yes, and no.
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At a planetary scale, Earth can't run out of freshwater thanks to the water cycle, a system that continuously produces and recycles water, morphing it from vapour, to liquid, to ice as it circulates around the globe.
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So this isn't really a question of how much water there is, but of how much of it is accessible to us.
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97% of earth's liquid is saltwater, too loaded with minerals for humans to drink or use in agriculture.
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Of the remaining 3% of potentially usable freshwater, more than two-thirds is frozen in ice caps and glaciers.
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That leaves less than 1% available for sustaining all life on Earth, spread across our planet in rivers, lakes, underground aquifers, ground ice and permafrost.
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It's these sources of water that are being rapidly depleted by humans, but slowly replenished by rain and snowfall.
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And this limited supply isn't distributed evenly around the globe.
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Diverse climates and geography provide some regions with more rainfall and natural water sources, while other areas have geographic features that make transporting water much more difficult.
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And supplying the infrastructure and energy it would take to move water across these regions is extremely expensive.
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In many of these water-poor areas, as well as some with greater access to water, humanity is guzzling up the local water supply faster than it can be replenished.
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And when more quickly renewed sources can't meet the demand, we start pumping it out of our finite underground reserves.
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Of Earth's 37 major underground reservoirs, 21 are on track to be irreversibly emptied.
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So while it's true that our planet isn't actually losing water, we are depleting the water sources we rely on at an unsustainable pace.
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This might seem surprising – after all, on average, people only drink about two liters of water a day.
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But water plays a hidden role in our daily lives, and in that same 24 hours, most people will actually consume an estimated 3000 liters of water.
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In fact, household water – which we use to drink, cook, and clean – accounts for only 3.6% of humanity's water consumption.
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Another 4.4% goes to the wide range of factories which make the products we buy each day.
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But the remaining 92% of our water consumption is all spent on a single industry: agriculture.
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Our farms drain the equivalent of 3.3 billion Olympic-sized swimming pools every year, all of it swallowed up by crops and livestock to feed Earth's growing population.
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Agriculture currently covers 37% of Earth's land area, posing the biggest threat to our regional water supplies.
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And yet, it's also a necessity.
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So how do we limit agriculture's thirst while still feeding those who rely on it?
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Farmers are already finding ingenious ways to reduce their impact, like using special irrigation techniques to grow "more crop per drop", and breeding new crops that are less thirsty.
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Other industries are following suit, adopting production processes that reuse and recycle water.
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On a personal level, reducing food waste is the first step to reducing water use, since one-third of the food that leaves farms is currently wasted or thrown away.
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You might also want to consider eating less water-intensive foods like shelled nuts and red meat.
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Adopting a vegetarian lifestyle could reduce up to one third of your water footprint.
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Our planet may never run out of water, but it doesn't have to for individuals to go thirsty.
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Solving this local problem requires a global solution, and small day-to-day decisions can affect reservoirs around the world.
