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Estimating Watershed Degradation Over the Last Century

October 2016

Healthy watersheds can naturally filter water before it reaches downstream users, but degradation of these ecosystems is leading to increased treatment costs for many cities. These costs are documented in a study authored by scientists at The Nature Conservancy, Yale University and Washington State University, titled “Estimating watershed degradation over the last century and its impact on water-treatment costs for the world’s large cities.”

Their research shows that increased agriculture and development in and near watersheds has led to high levels of sediment and nutrient pollution in many watersheds, with resulting increases in water treatment costs—by up to 50 percent in nearly a third of large cities worldwide. The study also highlights strategies some cities have used to preserve natural ground cover in their watersheds.

Estimating Watershed Degradation Over the Last Century
Estimating Watershed Degradation Over the Last Century
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