Water stress
Water stress describes pressure on freshwater resources when withdrawals are high relative to renewable supply after environmental water requirements are considered. Under Sustainable Development Goal indicator 6.4.2, it is calculated as total freshwater withdrawal by major sectors divided by available renewable freshwater resources after environmental flow needs, expressed as a percentage.
In simple terms
The Sustainable Development Goal indicator provides a consistent national measure of withdrawal intensity. Higher percentages indicate greater competition and pressure on renewable resources. The indicator does not by itself capture seasonal or local variation, water quality, infrastructure, affordability, allocation among users, or dependence on non-renewable groundwater. Basin-level and social information is therefore needed to understand operational impacts and lived water insecurity.
Why it matters
Water stress can signal growing competition among households, agriculture, industry, energy, and ecosystems and can expose operations and supply chains to disruption. Because a single national percentage averages diverse conditions, decisions should combine it with watershed, seasonal, quality, and access data rather than treating the indicator as a complete diagnosis of water scarcity.
Example
For example, two facilities can report similar withdrawals but face different stress because one operates in a basin where withdrawals already approach available renewable supply during the dry season. The ratio helps identify pressure, while local flow, quality, allocation, and ecosystem data guide the response.
How it differs
Water scarcity
Water stress is commonly an indicator of withdrawal pressure on renewable resources; water scarcity is a broader condition shaped by physical supply, quality, infrastructure, institutions, access, and demand.