by Andrea Erickson, Managing Director, The Nature Conservancy
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.
“Nature can provide value that extends far beyond savings in water treatment costs.”
- Andrea Erickson
While nature-based solutions aren’t new, they are underutilized. A recent study released by The Nature Conservancy shows that four out of five of the 4,000 largest cities in the world could improve water quality using nature-based solutions. One in six of those cities recoup the costs of these source water protection activities through savings in annual water treatment costs alone.
Nature can provide value that extends far beyond savings in water treatment costs. Nature-based solutions designed to improve local water quality can have a positive impact on some of the greatest global environmental challenges we’re facing. If the 4,000 largest cities invested in upstream land conservation with the main goal of protecting water sources, we could also reduce the risk of regional extinctions for 5,400 animal species, improve the health and well-being of more than 1 billion people, and store and capture more than 10 gigatonnes of CO2 each year. These benefits could never be realized by relying on gray infrastructure alone to improve our water security.
These numbers are big — but on the ground, they translate into real impacts that help real people and protect real places. For example, in the Cauca Valley in Colombia, planting avocado trees to reduce erosion on pastureland gave farmers a new source of income. High in the Andes Mountains, Quito’s efforts to protect its water source also provides habitat for the rare Spectacled Bear. In China’s Zhejiang Province, bamboo farmers are transitioning to organic farming methods to reduce fertilizer runoff and increasing their income by selling their product for higher prices. And in Bolivia’s Santa Cruz Valley, water protection efforts also reduced instances of water-borne disease in rural communities.
Protecting water sources effectively requires the cooperation of many entities. To grow sustainably, cities will need to play leading role in protecting and preserving water sources, but they cannot do it on their own. All those that depend on reliable water sources, including businesses, electric utilities, farmers and ranchers, will need to come together to jointly invest in upstream conservation. Water funds are a mechanism for doing just that.
One great example of a water fund at work is in Nairobi. The Tana River supplies 95 percent of the water for Nairobi’s 4 million residents, and for another 5 million people living in the watershed. Since the 1970s, the unchecked expansion of farming, quarrying and dirt road construction across the Upper Tana led to land degradation that clogs the river with sediment, impacting water delivery to users in Nairobi and energy generation at the hydroelectric facility.
The water and electric utilities, beverage companies and a range of private sector partners came together to launch the Upper Tana-Nairobi Water Fund. The fund was designed to provide upstream farmers with the training, resources and equipment they need to help keep soil on their farms and not in the river, creating cleaner water and reaping the benefits of higher crop yields and more stable farms. The fund has downstream benefits including improved water yields and reduced sediment in the river. An analysis of the fund’s expected returns showed that even by conservative estimates the selected watershed interventions could deliver a two-to-one return on investment on average over a 30-year timeframe.
During a recent trip to Kenya, my conversations confirmed why the fund has been successful. From conversations with the CEO of the Nairobi water company, some of the 15,000 small-holder farmers that have been part of the effort, and the CEO of an agricultural export company, I heard one message that was consistent: it’s in their best interest to make this work. Taking care of the land will ensure the longevity of the agricultural community and create a more sustainable water future throughout the watershed.
Currently, dozens of water funds exist around the world, but more cities could experience similar benefits as New York or Nairobi by developing their own water funds to pair with investments in gray water infrastructure. Nature-based solutions used to improve water quality and quantity can also help us reduce our carbon footprint, maintain critical ecosystems and build healthier, more resilient communities in the face of climate change. By realizing that nature is vital water infrastructure, we start down the path of giving nature the credit it deserves as a provider of solutions.