Everyone knows that water is essential for life and nearly every aspect of human endeavor. The UN Sustainable Development Goals call out water security in Goal 6, Clean Water and Sanitation, but water security is fundamental to achieving any further kind of sustainable economic and human development. None of the other goals - addressing poverty, hunger and health; mitigating and adapting to climate change; providing affordable energy; creating more sustainable cities and communities—can be achieved without safe and secure water supplies.
However, in the economics of water security, water is usually the vehicle of the value, rather than its source. The infrastructure and institutions established to deliver water when and where it is needed determine how economic and social value are created and distributed. It is reliable access to water of a certain level of quality that we value, not just the water molecule itself.
This raises the question: are we investing in the most valuable solutions? Most communities tend to rely only on "grey infrastructure" to deliver water security, such as reservoirs, aqueducts, and treatment plants. But experience shows that natural infrastructure, such as the healthy forests, wetlands and river ecosystems from which we source our water supplies, also delivers value.
Widespread degradation of watersheds around the world is leading to impaired downstream water quality, and diminished and less reliable flows. Deforestation, poor agricultural practices and other unsustainable land uses have caused moderate to high degradation in 40 percent of the world’s urban watersheds. Investments in these landscapes should be part of a comprehensive approach to water security.