Public lands protect our water supply: the journey of a drop to your faucet

Water appears in an instant when you turn on your kitchen tap for a morning coffee, fill a glass, rinse a plate, water a houseplant, or complete any number of household chores that involve your tap. These are ordinary parts of the day, yet most people rarely stop to wonder where that water was before it reached the taps we use. The journey of a single drop of water often begins far upstream in the forests and headwater streams of our public lands.

The connection between public lands and our faucets runs through rivers. Rain and snowmelt from these landscapes feed small streams that eventually join larger rivers. As David Moryc, American Rivers’ Senior Director of River Protection, explains, “rivers are an essential and major source of clean, low-cost drinking water.” That is why protecting public lands upstream can help protect the quality of the water that eventually reaches our homes.

Where our water begins: public lands 

From healthy forests and riverside lands, riparian areas to wetlands and meadows, all of these key areas  play a role in how water moves in a watershed. They help prevent flooding, store water, reduce erosion, support cooler and more reliable stream flows, provide habitat for wildlife, and help rivers remain healthy as they make their journey downstream. 

These healthy rivers and surrounding landscapes are important for wildlife and for people, too. Most of us who hunt, fish, swim, or hike on rivers regularly find ourselves on public lands, and for a good reason: they are home to the largest number of healthy, free-flowing rivers in the nation. These freshwater arteries support wildlife, incredible and economically important outdoor recreation, and us — as the largest single source of drinking water for Americans.  U.S. National Forests alone provide drinking water to over 60 million people in 3,400 communities across 33 states, and they are source areas for many important rivers as well as local and regional aquifer systems. Lesser known, but no less important, are the water resources that flow from Bureau of Land Management lands — estimated to provide drinking water to 1 in 10 Americans in the Western United States.   

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One particularly important part of our national forests is their Inventoried Roadless Areas — relatively undeveloped landscapes where road construction has been limited, playing an important role in supplying clean drinking water to downstream communities. Across the contiguous United States, these areas help protect more than 80,000 miles of rivers. 

An American Rivers-commissioned 2026 analysis by Conservation Science Partners helps illustrate the scale of that connection. The analysis identified over 10,000 watersheds influenced by U.S. Forest Service Roadless Areas, either because at least part of the watershed lies within those areas or because it is located within 100 river miles downstream. At least 27.4 million people depend on these IRA-influenced watersheds as a source of drinking water through public water systems. Of those, 22.9 million depend on watersheds located downstream of the roadless areas themselves.  

Behind those numbers are everyday moments: filling water bottles before school and cooking dinner, all while trusting that clean water will be there when you turn on the tap. 

The report also found that forested landscapes generally provide more consistent and higher-quality water yields than other land-cover types, in part because trees help slow rainfall and forest soils allow more water to soak into the ground. Moryc describes forests, headwaters, wetlands and healthy rivers as “natural reservoirs and filters to provide low-cost sources of drinking water while supporting nature.” 

How does water travel from public lands to communities? Follow the water downstream.

From these headwater landscapes, our drop enters small creeks and streams. As those waterways join larger tributaries and rivers, they carry water toward the communities that depend on them. Some of these waterways are small enough that many people would never think of them as part of their drinking-water system. By the time a river reaches a city, its health has already been shaped upstream by the streams and landscapes that feed it. 

From the river to your faucet: how does river water become drinking water?

Travel farther downstream, and here we find larger rivers and reservoirs — water sources that communities rely on frequently without realizing it. That connection becomes more tangible when looking at individual communities. Moryc pointed to Denver, Colorado, as one example: 30 percent of Denver’s water supply comes from watersheds containing Inventoried Roadless Areas. 

How do public lands protect drinking water quality? What happens upstream does not stay upstream.

When streams and floodplains are degraded, erosion increases, or healthy river corridors are lost, the effects can travel downstream, too. Roads are one example: logging roads can increase erosion and sediment delivery to streams by up to 850 percent compared with rates in undisturbed habitat. U.S. Forest Service research has repeatedly identified road building as a major human-caused source of soil and water disturbance, damaging watershed health in national forests. 

That is one reason protecting drinking water cannot begin only where people withdraw water for their communities. It has to include the broader watershed, from small headwater streams to floodplains, and the landscapes surrounding them. 

This connection between healthy rivers, healthy landscapes, and drinking water is also part of why American Rivers works beyond the river channel itself. As Moryc explains, “American Rivers is working on policy and projects at the federal and state levels to protect our rivers and drinking water supplies.”