A Natural Solution to Water Security

New report analyzes 4,000 cities to demonstrate the health, climate and biodiversity benefits of source water protection.

As cities around the world use nature-based solutions to improve water quality, they are learning that those solutions provide so much more. Photo © Kevin Arnold

Wen you turn on the tap in Quito, Ecuador, the water that emerges does so after a long journey. It starts high in the Andes, in springs and streams that merge into rivers, and flows downhill.

There, the water filters through cloud forests and grasslands, picking up more spring water and snowmelt from glaciers, continuing its downstream journey until it eventually reaches Quito’s municipal water system.

The quality of the water entering Quito, and many other cities around the world, is directly dependent on the landscapes through which the water flows. Good land management can promote water filtration, produce more reliable downstream flows, and reduce the amount of sediments and nutrients that can make their way into the rivers, springs and aquifers that feed urban water supplies.

The city of Quito and upstream landholders have invested in taking care of their water sources for many years.

In Bloomington, Illinois, agricultural runoff caused nitrate levels in the water supply to surpass federal standards. But a combination of wetland restoration and improved farming practices has shown to effectively remove inflowing nitrates at a cost-competitive rate. Photo © Cristina Rutter/The Nature Conservancy

Unfortunately, many of our lands around the world are not always managed well, which leads to impaired downstream water quality and flows. Deforestation, poor agricultural practices and other land uses have led to moderate to high degradation in 40 percent of the world’s urban source watersheds. Water quality and quantity challenges have typically been met with the addition of more gray infrastructure—including aqueducts, reservoirs and treatment plants—to move and treat water for human and industrial purposes.

But the path to water security doesn’t have to be lined exclusively in concrete. Improving the health of the lands around our water sources—a strategy called source water protection—can improve water quality, restore reliable water flows and bring added benefits to local ecosystems and communities.

There are many effective source water protection activities, including forest protection, reforestation and improvement of agricultural practices on lands near water sources.

Monterrey, Mexico has experienced flooding and drought during recent years. The city is investing in reforestation and many other activities designed to improve the lands within the watershed. Through this work, the watershed’s capacity to absorb available water could increase by 20 percent. Photo © Alejandro Lopez-Serrano/TNC

To implement these strategies, The Nature Conservancy is working with cities and water users around the world to create water funds, which enable water users to collectively invest in source water protection activities for the purpose of securing better water quality and improving the health and well-being of local communities. The Conservancy and its partners already have 29 water funds in operation and another 30 in development. The first of these was created more than 15 years ago—in Quito.

Drought and sedimentation of reservoirs is causing water stress in São Paulo, Brazil. To decrease erosion in the watershed, about 13,000 hectares of land were identified for reforestation. Reforestation can help the city meet carbon storage goals—each hectare can store around 102 metric tonnes of carbon. Photo © Scott Warren

“Communities downstream are going to benefit if their water comes when they want it and how they want it,” said Andrea Erickson, managing director for water security at The Nature Conservancy.

“Source water protection can provide that connection between downstream users and upstream individuals—the farmers, ranchers and other community members that are a critical part of the solution.”

At a time when there is growing demand for limited water supplies—and when climate change is making availability of water even more uncertain—source water protection is a powerful strategy to not only secure clean water but also mitigate and adapt to climate change, protect biodiversity, and support human health and well-being across watersheds.

Read and download full report here

Read full article at: The Nature Conservancy