Nature is often admired for its beauty, but rarely for the critical role it plays in moving, storing and filtering water before it comes out of our taps. Rivers, lakes, soil, plants and trees serve as our most basic water infrastructure. While investments in gray infrastructure have helped manage increasing water demands around the world, our future does not need to be lined exclusively in concrete. By investing in and maintaining the land around our water sources, we can create a more water-secure future for cities and communities while generating a number of other benefits for people and nature.
Currently, cities around the world spend billions of dollars to move and treat water, and that’s expected to rise into the trillions by 2025. More than 1.7 billion people currently live in the 4,000 largest cities on Earth, and that number will only grow in coming years. Finding enough clean, reliable sources of water to meet those growing demands won’t be easy given that 40 percent of our watersheds are seeing moderate to high degradation from development, deforestation and the expansion of agriculture.
Nature, however, can help. Investments in nature-based solutions such as protecting existing forests, planting trees and shrubs on pastureland and using cover crops on fallowed agricultural land can reduce water treatment costs by minimizing soil erosion, increasing water infiltration to provide more reliable water flows year-round and preventing fertilizer runoff into water sources.
Many cities are already investing in nature-based solutions to reduce water treatment costs. New York City invested in preserving three watersheds as an alternative to building a new $8 billion treatment plant. Today, the New York City water supply remains the largest unfiltered supply in the United States, saving the city more than $300 million a year on water treatment operation and maintenance costs. Rio de Janiero, São Paulo and Seattle are just a few other cities that are seeing savings by investing in nature-based solutions.