All water problems are local

It is useful to know how climate change is likely to impact the water cycle at the global scale and IPCC reports represent our best understanding of those impacts over the next few decades to century. But as we have discussed elsewhere, all water problems are local. In very few situations is it even feasible, let alone prudent, to transfer water long distances. Every place has its own set of challenges, institutional and infrastructure legacies, financial or other resource constraints, and concepts of social acceptability.

Generally speaking, places currently experiencing water stress or expecting to experience water stress in the foreseeable future have only a few basic options: a) have fewer people, b) force/incentivize people to use less water, c) increase storage and/or minimize losses within the system, d) reuse water, or e) get water from elsewhere. The capacity to cope with water stress (short or long-term) generally increases with wealth, though in wealthier countries more infrastructure is potentially at risk. As major population centers have already begun to struggle with water shortages it has become clear that massive investments in water technology and security infrastructure can allow wealthy nations to offset higher levels of water stress without remedying their underlying causes. Less wealthy nations, on the other hand, remain vulnerable and have fewer options in water development.

• Salt Lake City