
The list of 100 ranks countries based on the amount of renewable freshwater available per person each year, expressed in cubic metres per capita.
It takes into account long-term supplies from rivers, lakes, groundwater reserves, and cross-border water inflows, while also factoring in the size of the population.
It has been noted that the top 20 countries are largely clustered across the North Atlantic region, northern South America, the Congo Basin, the Pacific, and other sparsely populated nations with abundant renewable water resources.
The differences within the ranking are substantial; Iceland‘s freshwater availability per person far exceeds that of most countries in the Top 20, while even those near the bottom of the list enjoy significantly greater water resources than many densely populated or water-scarce nations. However, it is worth noting that much of the available water may be difficult to access, protected for environmental reasons, seasonal in nature, located far from population centres, or affected by fluctuations such as floods and droughts.
Note: The ranking is best understood alongside other factors such as water consumption levels, water stress, the quality of infrastructure, water management policies, access to safe drinking water, and climate-related risks.