This post is the first installment of our blog series, Nature for Water. In this series, we'll explore the benefits, opportunities, and best practices of using natural infrastructure like forests to secure clean water.

Securing clean water is becoming increasingly difficult in the United States. Infrastructure like dams and treatment plants are aging, water demand is increasing, and more frequent extreme weather events like wildfires and flooding are driving up the cost of water management.

It’s a complex problem, but one of the potential solutions is decidedly low-tech: Invest in nature.

WRI’s new publication, Natural Infrastructure: Investing in Forested Landscapes for Source Water Protection in the United States, pulls together the insights of more than 50 authors from the front lines of efforts to integrate “natural infrastructure” into water management. Incorporating strategically secured networks of forests, wetlands, and floodplains to complement existing “built” infrastructure can reduce water-management costs and effectively secure clean drinking water.

The publication, co-edited with Earth Economics and Manomet Center for Conservation Sciences, provides comprehensive guidance to help water utilities, municipalities, businesses, land management organizations, and other decision makers better manage their water systems by securing forests and other ecosystems. The guide paints a picture of the current “state of practice” of natural infrastructure investment, showing that there is ample opportunity for securing natural infrastructure for water and an expanding toolkit for doing so.

Natural Infrastructure: An Essential Tool for Securing Clean Water

Forests and other ecosystems provide proven benefits when it comes to water security. For example, forests have sturdy, long-lived roots that help to anchor soil against erosion. Multiple layers of vegetation help slow falling rain and reduce its erosive force. And forests also promote infiltration of water into the soil, minimizing flooding and allowing for nutrient uptake by vegetation and soil microbes.

There is widespread opportunity to integrate this natural infrastructure into traditional water management strategies, alongside built infrastructure like treatment facilities and mechanical chillers. In fact, several locales are already pursuing this option—with the potential to reap significant benefits.

For example, the water utility in Eugene, Oregon, already has sophisticated water treatment capabilities. However, in response to increased residential development along its drinking water source, it’s also investigating options to establish vegetated buffers that can shield streams and other upstream water sources from run-off and other land development impacts. This practice could preclude downward trends in source water quality, save the utility on treatment costs, and generate a number of co-benefits like quality wildlife habitat.

The water utilities on the Northern Front Range of Colorado have intricate systems of traditional infrastructure to provide high-quality drinking water. But in the face of catastrophic wildfire upstream, natural infrastructure options are increasingly critical. Wildfires in these utilities’ forested headwaters can cause massive sedimentation, which can clog water intakes, reduce reservoir storage capacity, and increase treatment costs. While robust “built infrastructure” is essential for managing these risks, Front Range utilities stand to save hundreds of millions by investing in measures like prescribed burning and mechanical thinning that reduce the occurrence of wildfire. Managing for fire risk also improves watershed function and reduces risk to local homes, wildlife, and fisheries.

How Do You Scale Up Natural Infrastructure for Water?

But despite a growing number of cities investing in nature for water, the strategy is still considerably underutilized. The reasons for this are varied. For example, water utilities have tight financial resources and competing demands for those resources. Many current financial accounting standards favor business-as-usual built infrastructure. But what it really comes down to is a lack of know-how on identifying opportunities, designing programs that use natural infrastructure, and implementing projects.

That’s where our new publication comes in. The report provides the insights, analysis, and case studies necessary to help all levels of water decision makers—from the newcomer to the expert—understand and implement natural infrastructure strategies for water. The guide helps create a “source water toolkit,” and offers critical local knowledge, relationships, and expertise. As managing water becomes increasingly complex and costly, decision makers must rely on all tools in their arsenal. Investing in forested landscapes is not only good for the balance sheets of utilities, municipalities, and businesses—it’s a solution with a wide array of direct benefits to communities across the United States.

  • LEARN MORE: Download our full report. And be sure to check back regularly for more installments of our blog series, Nature for Water, where we’ll highlight the benefits, opportunities, and best practices of using natural infrastructure to secure clean water.