Forests act like a sponge. The trees and soil within them absorb rainfall and melted snow, reducing the risk of extreme flooding. Also, the water absorbed eventually flows into rivers and streams that provide us with a steady supply of water. Forests also act like a filter. They keep water clean by preventing the runoff of chemicals and soil into waterways.
What does this mean for people?
- A steady supply of water. Almost 60 percent of America’s drinking water originates from national forests—mainly the rivers and streams that run through them.
- Fewer extreme floods. Forests, especially those that run beside streams, retain and temporarily store rainwater.
- More recreation opportunities, such as fishing and kayaking in the waterways forests help keep clean.
- Lower costs associated with water treatment. Every 10 percent increase in forest cover in a watershed leads to a 20 percent decrease in costs for water treatment downstream from the watershed. Filtration provided by just one national forest (Wayne National Forest in Ohio) is valued at more than $3 million annually.
The loss of forests through deforestation—which, in the U.S., is primarily due to sprawling development—threatens the ability of forests to act as sponges and filters. So does forest degradation, which, in the U.S., is largely the result of insects and diseases that damage trees. Scientists predict that, by 2071, nearly half of the freshwater basins in the U.S. may not be able to meet the monthly demand for water—partly due to a decline in forest health. Jeopardizing the quantity and quality of our water supply is particularly concerning, given that our population is increasing.
How are we protecting the nation’s water supply?
Our approach related to water is three-pronged. In our Innovation Lab, we incubate new tools and scientific research to help solve complicated puzzles and empower the forestry field. We create place-based partnerships in cities and large, rural landscapes so we can work with others to develop and implement enduring, science-based data and plans that relate to planting trees and taking care of the trees we already have. And we build movements that inspire and empower actions—such as the creation of new reforestation policies—at a large scale. Following are several examples of projects related to our approach.
American Forests in Action
Place-based Partnership: Northern Rockies
In the western U.S., water quantity and the health of whitebark pine trees are intertwined. Whitebark pine trees grow in high-elevation forests, upwards of 6,000 feet. Much of the drinking water from watersheds within the range of whitebark pine trees comes from snow that has melted and run into several major river systems. Whitebark pine trees hold the snow in place (their candelabra-shaped wide crowns provide shade, which slows snow melt) in the winter and gradually release it in the warmer months. But most whitebark pine trees have fallen victim to a non-native fungus, white pine blister rust, that prevents the flow of nutrients within the tree. To address this, American Forests is helping to grow and plant rust-resistant whitebark pines.
Movement Building: Land and Water Conservation Fund
In the U.S., millions of acres of forests don’t have the protection they need, which jeopardizes the important role forests play in keeping our water clean. Each year, forests in national parks, on private property and elsewhere are promised $900 million from the Land and Water Conservation Fund (LWCF). The funding is to be used to protect these forests by, for example, implementing climate-smart forestry practices. But in recent decades, $20 billion of this money has been diverted away from its intended purpose. Now, a bipartisan bill aims to provide full, dedicated funding to the LWCF. Read how you can support this legislation.