Author: Hugo Contreras Zepeda
Cities throughout Latin America are searching for the best solutions to secure water for their residents and decrease their vulnerability to droughts and floods caused by extreme weather events. Natural or “green” infrastructure has proven to be competitive with, and often more efficient than, built or “grey” infrastructure. Yet economic and scientific tools have not been readily accessible for decision-makers to determine optimal solutions, combining green and grey infrastructure in ways that are tailored to each city’s specific needs.
Photo: © Scott Warren
The Nature Conservancy, in partnership with C40 Cities Climate Leadership Group and the International Water Association,has released a new report, Urban Water Blueprint: Mapping Conservation Solutions to the Global Water Challenge, which analyzes the state of water among more than 2,000 watersheds and 534 cities worldwide. The report offers science-based recommendations for natural solutions that can be integrated alongside traditional infrastructure to improve water quality.
Photo: © Ami Vitale
As part of its global analysis, the report evaluated more than 60 cities in Latin America with at least one million inhabitants. Natural solutions, including reforestation and stream bank restoration, could improve water quality for more than 100 million people living in the top 25 largest Latin American cities alone. According to the report, the cities in the region with the highest watershed conservation potential are Bucaramanga and Bogotá, Colombia and Curitiba, Brazil. Curitiba, for example, is a fairly large city (3.5 million inhabitants) with significant seasonal waterfluctuations and relatively small watersheds, but has clear potential for landscape restoration and forest protection to improve water quality. With a large population concentrated in a relatively small area, there is also an opportunity for the local utility and main water users in Curitiba to collectively generate investment in watershed conservation.
Photo: © Scott Warren
The Urban Water Blueprint and accompanying interactive website serve as a tool for decision makers in evaluating water quantity and quality risk across the world’s largest cities, the steps cities have taken to overcome water stress, and the cost-benefits of incorporating natural solutions. Since the benefits of natural solutions often extend beyond municipal boundaries, the report outlines unique financing mechanisms that cities, water utilities and partners can use to share the cost of implementing these solutions in shared watersheds.
Although watersheds are vital to the urban water supply, they typically receive little investment. To that end, the Inter-American Development Bank has partnered with the Global Environmental Facility, Fundación FEMSA and The Nature Conservancy to work with Latin American cities to implement water funds. These funds are financial mechanisms that facilitate conservation investments in strategic parts of the watershed that support the water supply. Today, there are 17 funds in operation that positively impact a number of cities. The findings in this report will allow for a more strategic approach, targeting the conservation where it has the greatest potential for a return on investment.
Photo: © Timothy T. Lindenbaum, The Nature Conservancy
Source watershed conservation plays an important role in securing an adequate, clean water supply, and protecting water at its source can be cheaper and more efficient than treating it after it has already been polluted. Investing in natural solutions such as land conservation, reforestation, stream bank restoration, improved agricultural practices and forest fire management can reduce sediment and nutrient pollutants that flow into drinking water sources.
Cities that embrace both natural and traditional engineered infrastructure solutions will not only meet future water demand; they will reshape our planet’s landscape for the better.
Visit nature.org/waterblueprint to explore for yourself.
Photo: © Erika Nortemann, The Nature Conservancy