Water use in LCA: managing the planet’s freshwater resources

Freshwater is one of the planet’s most valuable resources being an essential life-sustaining element which cannot be substituted. Acting as the source of drinking water and the basis for hygiene and food supply, it is indispensable for humans, while at the same time ensuring biodiversity and pivotal ecosystem functions on which ultimately we all depend. We are witnessing a steadily worsening situation of rapidly decreasing freshwater resource availability which threatens 1.1 billion people around the globe lacking sufficient access to safe drinking water (UN 2006). Spreading water scarcity in many regions of the world endangers food production (about 70% of today’s global freshwater consumption feeds agriculture!), puts food security at risk, and burdens human health due to malnutrition (e.g., in Asia and Africa). The overexploitation of surface water bodies and (fossil) groundwater for the soaring agricultural production (e.g., in China, India, Western USA) may jeopardize the freshwater abundance of future generations. Irrigation and damming cause fragmentations of river basins drastically reduce the downstream freshwater availability and alarmingly threaten aquatic and terrestrial ecosystems. Inappropriate water resource management endangers ecological functions and biodiversity, provokes disturbed water cycling and desiccation of rivers, streams, and land. If all that were not bad enough! On top, climate change promises to intensify the looming water crisis by changing rainfall patterns and inducing elevated evaporation and dramatic droughts in many regions of the world: Some 20% of the increase in water scarcity in the coming decades will be caused by climate change according to recent UN estimates (UN 2006). Being a fundamental building block for human civilization and economic development, freshwater also is a strategic resource, just like energy (Wall Street Journal 2008). Freshwater resources and their allocation increasingly play a central role in poverty alleviation and urban water supply, facing growing competition with other economic sectors particularly in low and middle income countries. Rapidly rising urban populations mount the pressure to shift water from agriculture to vastly expanding cities (e.g., in China). Global trade of manufactured goods and services, all of which require water at some point, fuel the demand for capturing the freshwater userelated environmental, economic, and social impacts (for definition of freshwater use, see Section 2). This is where life cycle-based sustainability assessment concepts come into play. Particularly, life cycle assessment Int J Life Cycle Assess (2008) 13:451–455 DOI 10.1007/s11367-008-0028-6