At the end of March, the United Nations held its first Conference on Water in nearly a half century. Its location—New York City—provided a compelling geography to learn from the past century of water management with its emphasis on valuing water as a fundamental resource for people and a corresponding focus on protecting and providing clean water.
For good reason—in fact, about 2 billion good reasons—much of the dialogue at the Conference focused on how to ensure that everyone in the world has access to clean water and sanitation (about 2 billion people lack access to safely managed drinking water and 3.6 billion, nearly half the world’s population, don’t have access to safely managed sanitation).
But the dialogue also revealed an emerging evolution in thought about what water is, what it provides, and how it should be managed. This evolution starts from the foundation of valuing water and expands toward valuing resilient systems.
This evolution is not a replacement or dilution of the primacy of valuing water as a fundamental resource for people. Rather, it’s a recognition that resilient living systems will be—and, in fact, have always been—the actual source of clean water for people. Further, when we manage for resilient systems, they can provide clean water for people, but they can also provide a diverse range of other benefits and services.
Let’s start from the source. New York City is justifiably celebrated for its water system. It is a marvel of engineering: 19 reservoirs and hundreds of kilometers of tunnels bringing some of the cleanest drinking water in the world to nearly 10 million people.
But you need to look past that engineering to see why New York City’s water is among the cleanest drinking water in the world. The foundation for that marvel of engineering is a marvel of nature: hundreds of thousands of acres forests, wetlands, rivers, streams and carefully managed farms in the Catskills Mountains north of the city.
New York City had long understood the relationship between healthy land and clean water, but in the 1990s they confronted a choice. New drinking water standards were kicking in, requiring all municipal drinking water systems to have physical filtration. To that point, New York treated its water but did not filter it before treatment. A filtration plant would have cost $10 -12 billion and would have been one of the largest public works projects ever implemented by a city.
Working with state and federal agencies, local communities and landowners, the city was able to meet the new drinking water standards without building a filtration plant. Instead, they doubled down on their commitment to managing the source of water to ensure it was even more clean and secure.
To date, the city has spent over $2 billion on acquiring land (e.g., forests and wetlands), restoring stream banks, replacing septic systems, and working with farmers on sustainable farm management plans. Yet this is far less than even what the operating expenses of the filtration plant would have been, let alone the initial capital expenditure.
New York City has the largest unfiltered water system in the country. Or, more precisely, the largest water system without engineered filtration, because the forests and wetlands of the Catskills act as a giant filtration plant. They also act as a beloved recreational space for New Yorkers and habitat for wildlife.
The NbS that is the Catskills underscores a key reality: water comes from nature. And if we want that water to be clean, then we need to maintain healthy and resilient ecosystems that underpin the source of water.
But nature is not just an upstream source, it’s also a downstream recipient. People—and all the stuff they’ve made: buildings, factories, roads, etc.—affect water in myriad ways before discharging it onto land, into streams and wetlands, and into the groundwater.
That is, water doesn’t just come from nature and flow to people, water also comes from people and flows back to nature.
Thus, the health of lakes, rivers, and coastal waters—and the benefits they provide to people including recreation and fisheries—requires that we also take care of the water we send downstream to those systems. Nature-based solutions can also help with this challenge and, again, New York City provides an illustrative example.
About twenty-five years ago, New York City created its “Blue Belt” program to restore wetlands to help manage stormwater. Cities are full of impervious surfaces—roads, buildings, parking lots—resulting in high volumes of runoff during rainstorms. Typical management of stormwater gathers the runoff into sewers that rapidly discharge water—generally fairly dirty—into streams and then, in the case of New York, into coastal waters of the surrounding bays and harbors.
The wetlands that were created and restored in the Blue Belt system absorb stormwater runoff, hold it temporarily, and allow physical and biological processes to improve the water quality before it is released, resulting in both improved water quality and lower flood risk downstream. The program has helped reduce urban flood risk and has contributed to steadily improving water quality in New York’s coastal waters.
Nature-based solutions for stormwater management have another benefit: they are green spaces in an urban environment. These projects for managing stormwater can take the form of parks, wetlands, “daylighted” creeks, and wildlife habitat, and these investments can be prioritized for communities and neighborhoods that have historically lacked access to nature.
The world is rapidly urbanizing, and cities will confront a range of challenges, including dealing with larger floods and providing access to green spaces and nature for the mental and physical health of city dwellers. Well-planned and managed nature-based solutions can contribute to both challenges, providing cost efficiencies to strained city budgets.
These multiple benefits are a hallmark of nature-based solutions: clean water and lower flood risk and space for recreation and habitat for wildlife. The reason NbS for water management can provide diverse benefits is that they are not simply an engineered solution directed at clean water; rather they are investments in resilient systems, and systems are capable of supporting multiple benefits.
This evolution from valuing water as a resource to valuing resilient systems—systems capable of producing the resource of clean water but also many other benefits—was a key part of the dialogue last month in New York City at the UN Water Conference. Nature-based solutions are increasingly recognized as essential to meeting the Sustainable Development Goals – not just SDG 6 for clean water, but several others that focus on safety and human and ecosystem health. Despite this growing recognition, investment in NbS, from both the public and private sectors, lag far behind their potential.
A further recognition of the diverse values that flow from resilient freshwater systems came in the form of the Freshwater Challenge – the largest wetland and river restoration project in history, championed by the governments of Colombia, the Democratic Republic of Congo, Ecuador, Gabon, Mexico and Zambia.
The scale of restoration envisioned worldwide —300,000km of rivers and 350 million hectares of wetlands by 2030—is an impressive commitment to investing in healthy, resilient ecosystems that can provide diverse values to people.
Water will always remain an essential resource for people. But the living systems, the rivers and headwaters that underpin that resource, have always been more than that. They are recognized as a source of food, connection and inspiration across cultures. Water management that focuses on valuing water only as a resource overlooks a far wider range of opportunities and benefits that flow from management that values the resilient systems that produce, and then take back, the water we use.
