A free, public reference. Pick any two national water measures and see the relationship across every country with data — published raw, ranked, and sourced. Water security is not one number: a country can be water-rich in total yet stressed per person, or naturally dry yet secure because it's rich enough to desalinate. We show the measures side by side, label each for what it counts, and let you conclude.
Two-axis scatter across 212 countries, with a live correlation gauge, the Falkenmark scarcity bands, and the total ↔ per-capita ↔ stress-ratio switch as the first-class control.
Renewable internal freshwater divided by the people who depend on it, in cubic metres per person. This is the scarcity spine. Ranked from least to most, and read against the Falkenmark thresholds: below 1,700 is water stress, below 1,000 scarcity, below 500 absolute scarcity. It reorders the total-volume list completely.
Total renewable internal freshwater, in billions of cubic metres. Brazil, Russia and Canada top it — but the list mostly measures which countries are big and rainy, not whether their people have enough. For that, divide by population: see renewable freshwater per capita, where the order falls apart.
Freshwater withdrawn as a share of what nature renews each year. Above 100% means a country is drawing down more than its renewable supply — possible only by desalinating seawater or mining fossil aquifers that don't refill. Ranked from the most stressed down.
The share of each country's renewable water that flows in from outside its borders — upstream rivers and aquifers it doesn't control. Ranked from most dependent down. At the top sit countries that can look comfortable on the total-water figure while living on a supply a neighbour could dam, divert or foul first. 0% means every drop is generated at home.
The share of people with an improved drinking-water source on premises, available when needed and free from contamination. The highest bar the data sets for access. Ranked from lowest coverage up — availability in nature and access at the tap are not the same thing.
The share of people using an improved, unshared sanitation facility where waste is safely disposed of or treated. Ranked from lowest coverage up. The sanitation gap runs wider than the drinking-water gap almost everywhere.
A lower, broader bar than safely managed: an improved drinking-water source within a 30-minute round trip. Ranked from lowest coverage up. Where this number is high but safely managed is low, the gap is about contamination and reliability, not distance.
Renewable water per person, counted two ways: internal generation alone — the scarcity spine the site is built on — against the total actual figure that adds the inflow from upstream. For most countries the two are close and the points hug the diagonal. For the downstream ones — Egypt, the Netherlands, Iraq — the gap is enormous, and that gap is precisely the water they don't control. The dependency ratio is that gap, expressed as a percentage; read its ranking alongside.
Agriculture's share of national water withdrawal against income. The slope is steep and downward: in poor countries farming swallows almost all the water, while rich ones spend a far larger fraction on industry and cities. It isn't that wealthy countries irrigate less in absolute terms — it's that everything else they do with water grows faster than farming does.
Renewable freshwater per person against national wealth. Nature hands out water without regard to income, so the cloud is wide — but watch the Gulf, sitting at the bottom of the water axis and the top of the wealth axis, having engineered its way past natural scarcity with desalination money can buy.
The water-stress ratio against national wealth. Both the very poor and the very rich can run high stress — the poor through agriculture on thin supplies, the rich through desalination and aquifer mining. The number alone won't tell you which; the wealth axis helps.
Safely managed drinking-water access against national wealth. The climb is steep where countries are poor and flattens near universal coverage. Some naturally water-rich countries still have low access; some dry-but-rich ones are near universal. Availability isn't security.
Renewable freshwater per person against how long that person can expect to live. There is no slope: the correlation is essentially zero. The driest countries on Earth post some of the longest lifespans, and several of the wettest post the shortest. How much water nature provides is not what turns up in a lifespan — clean water and the wealth to deliver it are.
Rank countries by total renewable freshwater and Brazil, Russia and Canada lead the world. Divide by the people who drink it and the list falls apart. The gap between those two rankings is the most useful idea in water data.
Count only the water Egypt makes inside its borders and it's the most water-starved country on Earth. Count the Nile and it's fine. Both are true, and the gap between them is a number worth knowing: the dependency ratio.
A water-stress ratio over 100% means a country takes more than nature returns. Sometimes that's desalination. Sometimes it's pumping water that fell as rain ten thousand years ago and will never be replaced. Satellites can now tell which — and the answer is grim in the driest places.
Of all the freshwater people pull from rivers and aquifers each year, the biggest share by far goes to one thing: irrigating crops. In the poorest farming countries it's almost all of it. Where that share falls, you're looking at an industrial economy.
Nobody publishes a clean, country-by-country figure for how much water the world's data centres use. But the arithmetic is simple — electricity times a water-intensity number — so here it is, with the one assumption that matters left in your hands.
How much renewable water a country has is almost unrelated to how rich it is. But whether that water is safe to drink tracks wealth closely. And the Gulf shows what money buys when nature says no.
Plot how much renewable water a country has against how long its people live and you get no line at all. The driest places on Earth post some of the longest lifespans; some of the wettest post the shortest. Here's why.