Water Resources — Definition

Definition

Water resources are the water stocks and flows that support ecological systems and human uses, considered together with their quality, timing and accessibility. They include connected surface water and groundwater, rather than only visible rivers or reservoirs.

A large annual rainfall total does not guarantee a reliable supply in every season or locality. Likewise, a stored volume does not automatically provide safe water at a household tap. Managing water resources requires accounting for inputs, withdrawals, return flows, storage changes and ecological needs within a defined basin or aquifer, while distinguishing physical availability from the infrastructure and institutions that distribute it.