Clean Drinking Water for Millions of People at Risk as Trump Administration Targets National Monuments

Since 1906, U.S. presidents have protected millions of acres of public lands and waters through the establishment of national monuments, from the California Coastal National Monument to what is now Acadia National Park in Maine.¹ National monuments not only shield important ecosystems, cultural resources, and recreation hubs from threats such as drilling and mining but also provide essential services to communities across the country.

A new analysis finds that 31 national monuments designated since the Clinton administration and now potentially under threat from the Trump administration safeguard the supply of clean drinking water for more than 13 million Americans.² Additionally, 83 percent of the miles of rivers and streams passing through these public lands are uniquely protected by their national monument status, meaning they have no other substantial form of conservation protection. Yet today, the Trump administration’s threats to eliminate national monument protections in the name of expanding drilling and mining across U.S. public lands put these clean waters directly at risk from development and pollution.³

During his first term, President Donald Trump removed huge swaths of two national monuments—eliminating 85 percent of Bears Ears and nearly half of Grand Staircase-Escalante in the largest reversal of U.S. land monument protections in history.⁴ Those monuments were later restored by President Joe Biden,⁵ but when Trump took office again in 2025, his Department of the Interior drafted a strategic plan that called for the agency to “assess and right-size monuments,” hinting at additional future rollbacks.⁶ In February 2025, Secretary of the Interior Doug Burgum signed an order to “review and, as appropriate, revise” certain public lands protections, including national monuments.⁷ Press reports from April subsequently indicated that the Interior Department was considering cutting protections for at least six national monuments,⁸ and a May 2025 Department of Justice memo confirmed that the White House was exploring the legality of revoking national monument protections.⁹ Most recently, President Trump announced his nominee to direct the Bureau of Land Management: Steve Pearce, a former congressman with a record of opposing national monuments and voting to curtail Antiquities Act authorities.¹⁰

These threats to national monuments are consistent with a pattern of attacks to public lands in recent months, including the defeated proposal to sell off public lands in the Big Beautiful Bill¹¹ and ongoing actions by the Trump administration to eliminate or weaken protections on more than 175 million acres of public lands.¹² Already, President Trump has taken action to remove protections for vast ocean areas within the Pacific Islands Heritage Marine National Monument,¹³ and conservation supporters are concerned that additional national monuments could be next on the chopping block.¹⁴

National monuments protect uniquely valuable lands and waters from future mining, drilling, and other destructive development, with land managers tasked with prioritizing conservation of important resources. Removing protections for these areas jeopardizes their cultural, historical, and ecological significance. In many cases, national monuments also provide vital access to nature and outdoor recreation opportunities for communities that are considered “nature-deprived.”¹⁵

By protecting natural lands from development and associated pollution, national monument protections also help ensure clean water continues to flow through local rivers and streams, supporting aquatic ecosystems and downstream drinking water users. Removing those protections could put rivers, streams, and other drinking water sources at risk, exposing these waters to potential contamination from drilling and mining operations¹⁶ and potentially eroding the water filtration benefits provided by healthy natural lands.¹⁷

Overall, the 31 at-risk monuments evaluated in Conservation Science Partners’ analysis contain 21,000 miles of rivers and streams—almost double the mileage of rivers protected under the entire National Wild and Scenic Rivers System.¹⁹ Eighty-three percent of these river miles are uniquely protected by the national monuments, meaning they would not be otherwise shielded from development if their monument status were stripped away.²⁰ Many of these monuments also sit upstream of major river basins, such as the Colorado, Missouri, and Mississippi; on average, each monument helps protect the water quality of 859 miles of downstream rivers and streams.

Drinking water for more than 13 million Americans is directly supplied by watersheds within or downstream of these national monuments—including in the major metropolitan areas of Los Angeles, San Diego, Las Vegas, Phoenix, and Denver. Notably, the watersheds fed by rivers and lakes within national monuments serve areas that, on average, have higher proportions of historically marginalized populations. Among the 2,125 watersheds found to be affected by at-risk monuments, the average share of nonwhite residents was 32 percent—nearly twice the national average of 18 percent—indicating that the rollback of protections would have disproportionate impacts on nonwhite communities.

Moreover, many of the watersheds protected by national monuments already face potential declines in water availability due to climate change. According to the CSP analysis, 23 of the 31 monuments provide water to local watersheds that are expected to see further declines in water availability by 2040 due to climate change.²¹ Some cases are particularly stark: Nearly 90 percent of watersheds overlapping with the Grand Staircase-Escalante National Monument, for example, are expected to see declines in water availability by 2040. Maintaining existing clean drinking water sources will be particularly important in regions with reduced water availability. Additionally, drought-strained watersheds can see declines in water quality,²² particularly when accompanied by more frequent and intense wildfires.²³

Statistics for specific national monuments can be explored via the interactive map in Figure 1. Some examples are highlighted below.

San Gabriel Mountains National Monument, California

The San Gabriel Mountains National Monument—established by then-President Barack Obama in 2014 and expanded 10 years later—overlooks the city of Los Angeles and provides access to much-needed green space for the city’s residents and recreation opportunities for millions of visitors each year.²⁴ According to the new water analysis, this monument also protects drinking water for more than 5 million local and downstream users, 60 percent of whom are people of color and nearly 30 percent of whom are low-income residents.

Nearly all—96 percent—of the 1,124 river miles within the San Gabriel Mountains National Monument are uniquely protected by this land designation. Additionally, in a region already experiencing the detrimental effects of frequent droughts,²⁵ almost 60 percent of this monument’s local watersheds are expected to see further declines in water availability by 2040 due to climate change. An erasure of protections that exposes these lands to development and pollution could be harmful to the millions of downstream users in the San Fernando Valley reliant on the precious water for drinking and other uses.

Katahdin Woods and Waters National Monument, Maine

Located in northern Maine and designated in 2016 to permanently conserve more than 87,500 acres of donated forest land,²⁶ Katahdin Woods and Waters exemplifies the important role that national monuments can play in securing clean water, recreational opportunities, economic benefits, and cultural histories. Anchored by the East Branch of the Penobscot River and its tributaries, the national monument sits on the ancestral homelands of the Penobscot Nation, whose people historically traveled and utilized the river and whose culture remains deeply connected to it.²⁷ Although historic fish runs declined dramatically during the 19th and 20th centuries, river restoration efforts by conservation partners and the Penobscot Nation are allowing fisheries to rebound, offering hope for the future.²⁸

The new analysis finds that local watersheds intersecting Katahdin Woods and Waters rank among the top 73 percent of all watersheds nationally for their ability to produce clean water, while the monument’s conservation protections directly support the drinking water of thousands of downstream users. The monument also provides plentiful outdoor recreation opportunities for New Englanders and visitors alike, including opportunities for fishing in state-designated “‘Heritage Brook Trout’ waters” and for paddling whitewater traversed by writer Henry David Thoreau.²⁹

Colorado River Basin region’s national monuments

For millennia, the Colorado River has been the lifeblood of communities throughout the American Southwest, and its river basin is home to a number of iconic national monuments that could be in the Trump administration’s crosshairs for elimination and future drilling and mining. Four of those national monuments—Bears Ears; Grand Staircase-Escalante; Baaj Nwaavjo I’tah Kukveni – Ancestral Footprints of the Grand Canyon; and Grand Canyon-Parashant—protect a total of 8,775 river miles flowing into the Colorado River.³⁰ A vital resource for the seven states through which it runs, the Colorado River provides water to up to 40 million Americans.³¹ Cities including Los Angeles, Las Vegas, and Phoenix all source drinking water from the Colorado River. The river also supports agricultural production, hydroelectric power, recreational opportunities, and wildlife habitat.³²

For the past 25 years, the Colorado River Basin “has been experiencing a historic, extended drought” that has affected water supplies in the region and caused reservoir storage to fall to about half of its capacity.³³ With further declines projected due to climate change, conserving the region’s ability to produce clean water is particularly important to handle increased demand from the rapidly growing communities along the Colorado River.³⁴ Additionally, the quality and quantity of the Colorado River Basin’s water are strained by energy development in the area, with 395 existing uranium mines along the river corridor and 800 pending new claims.³⁵

Notably, while estimates in Figure 1 of the number of people with surface water protected by national monuments in the Colorado River Basin are impressive, these statistics substantially underestimate the full reach of those surface waters due to lack of available data. The CSP analysis did not account for the additional drinking water users who tap into water piped to Southern California via the Colorado River Aqueduct and therefore also benefit from upstream land protections.

Several national monuments in the Colorado River Basin and their importance as clean water sources are described below.

Baaj Nwaavjo I’tah Kukveni – Ancestral Footprints of the Grand Canyon National Monument, Arizona

Located in Arizona, Baaj Nwaavjo I’tah Kukveni protects almost 1 million acres,³⁶ including the entirety of the Grand Canyon watershed³⁷ as well as the history, cultural sites, and ceremonial grounds of many Tribal nations.³⁸ The new analysis shows that the monument also shields 1,688 river miles and more than 79,800 drinking water users in downstream watersheds from future threats.

The Grand Canyon area has a long history of controversial and harmful development. For decades, the region was open to uranium mining that had detrimental effects on nearby communities, contributing to kidney failure and cancer among the Navajo Nation³⁹ and leaving groundwater at risk of contamination.⁴⁰ In 2023, a coalition of 12 Tribes called on then-President Biden to protect the site and permanently preserve their ancestral lands and the health of the watershed of the Grand Canyon and surrounding communities.⁴¹ While President Biden’s designation of the national monument did not fully resolve all threats—with mining companies still holding preexisting claims and one active mine operating within the monument’s boundaries⁴²—its protections prevent new claims and other development that could substantially escalate the threat to local and downstream waters.

Bears Ears National Monument, Utah

President Obama established Bears Ears in 2016 in response to a proposal from a coalition of five Tribes—the Hopi Tribe, Navajo Nation, Ute Mountain Ute Tribe, Zuni Tribe, and Ute Indian Tribe of the Uintah and Ouray Reservation—who called for the protection of these culturally, spiritually, and historically significant lands.⁴³ These Tribes now guide the stewardship of the monument, protecting its rich cultural history and thousands of ancient cliff dwellings, community centers, rock imagery, and artifacts.⁴⁴

According to the new analysis, the monument also protects 2,274 river miles within its borders and contributes to the water quality of an additional 1,033 river miles downstream. More than 90,000 people in local and downstream watersheds rely on the water that Bears Ears supplies. If monument protections were eliminated, Bears Ears and the water it protects could be particularly vulnerable to threats from uranium mining.⁴⁵ President Trump’s downsizing of the monument in 2017 was followed by dozens of new mining claims⁴⁶ and more than 100,000 acres leased for oil and gas drilling in the region surrounding the monument, although the majority of those leases were later canceled.⁴⁷ While President Biden restored the national monument designation, the previous mining claims are a good indicator of what is likely to come if Trump were to roll back protections again.⁴⁸

Browns Canyon National Monument, Colorado

Browns Canyon National Monument protects 21,586 acres of public land in Colorado’s upper Arkansas River Valley.⁴⁹ Considered a “recreationist’s dream” by the U.S. Forest Service, which manages the monument jointly with the U.S. Bureau of Land Management, the area draws visitors from all over the country.⁵⁰ Many come to float the popular whitewater of the Arkansas River, and more than 100 miles of river flowing through the national monument are recognized as “Gold Medal trout waters.”⁵¹ For thousands of years, Browns Canyon has served as an important source of water transportation and drinking water.⁵²

According to the new analysis, Browns Canyon National Monument helps protect downstream waters used as a drinking source by more than 1.3 million people today, with 98 percent of the monument’s river miles uniquely protected by its national monument status. The area is expected to be heavily affected by climate change, with 100 percent of local watersheds projected to see water declines by 2040, making its water supplies even more precious and vulnerable.

Lack of access to clean drinking water is a major public health concern, consistently ranking as Americans’ top environmental priority.⁵³ Yet the Trump administration could be on the verge of reversing fundamental protections for public lands that serve as vital clean water sources. Looming threats to national monuments not only endanger iconic landscapes, cultural history, and recreation opportunities but also put the drinking water supply of millions of Americans needlessly at risk.

The authors would like to thank Jenny Rowland-Shea, Sam Zeno, Mona Alsaidi, Shannon Baker-Branstetter, Meghan Miller, Bill Rapp, and Sanjana Bettadpur from the Center for American Progress for their contributions to this report. They would also like to thank Patrick Freeman, Helen Kesting, and Lise Comte from Conservation Science Partners, as well as other external partners and reviewers.