Across the U.S., communities are facing increasingly frequent and damaging extreme weather events fueled by climate change. A growing biodiversity crisis is imperiling the abundant wildlife, clean water, and natural systems upon which every person in the country depends. And in nearly every corner of the country, another interrelated — albeit lesser-known — threat is lurking: the threat posed by aging dam infrastructure.
The risks associated with America’s aging and forgotten dams are rapidly rising. Climate change is amplifying the perils dams pose to downstream communities. Unnecessary dams are themselves accelerating the decline of nature. And with each year that passes, America’s list of obsolete dams grows longer and one year older. It is a recipe for disaster for both humans and the environment.
By some estimates, dams block 600,000 miles of river in the U.S. In the West, dams and human-built obstructions have modified the flow of 71% of river miles. The result is nothing short of widespread ecological damage.
The time has come to do something about it. As a country, we need to undertake a serious assessment of our nation’s dams, identify which ones have outlived their usefulness and which are worthy of upgrades, and commit to supporting a dam management and removal program aimed at strengthening community resilience and ecosystem restoration.
An idea whose time has come
Some of my earliest professional memories come from the late 1990s working for then-Interior Secretary Bruce Babbitt, typing up speeches and essays he had written about the importance of considering dam removal as a key tool to restoring fully functioning ecosystems. In 2000, I traveled with him to Redding, California to watch bulldozers take down the Saeltzer Dam on Clear Creek.
Located in the Central Valley on Bureau of Land Management land and built in 1912, Saeltzar Dam was part of a highly engineered water infrastructure system that blocked 95% of historic salmonid habitat. Removal of this particular dam — part of the Secretary’s Dam Busting Tour — was aimed at restoring access for spring-run chinook salmon and other anadromous fish (typing all those essays was when I learned both what “anadromous” means and how to spell it) to 12 miles of upstream spawning habitat on Clear Creek.
While originally built for irrigation and dredge mining, the dam had far outlived its usefulness and was depriving spring-run chinook salmon with access to spawning habitat, stranding them in low and increasingly hotter waters below the dam. Studies conducted since the dam was removed show that riparian vegetation has re-established, concerns about post-dam-removal sediment mobilization have waned, and just two years after dam removal, the U.S. Fish and Wildlife Service estimated that over 70% of spring-run chinook successfully passed upstream of the former dam site — compared to less than 1% previously.
As a country, we need to undertake a serious assessment of our nation’s dams and commit to supporting a dam management and removal program aimed at strengthening community resilience and ecosystem restoration.
At that time, removing an 88-year-old dam was still something of a novel project. As a country, we were familiar and comfortable with building dams. But taking them down? It felt like a risky experiment. Now, a quarter-century later, we can definitively say it’s an experiment that has worked over and over again.
The Legacy and Costs of Aging Dams across the United States
There are over 90,000 dams in the United States of various sizes, built for a wide array of purposes, including irrigation, flood control, hydroelectric power, and navigation. The vast majority of dams in the U.S. (97%) are owned by private entities, state or local governments, or public utilities. The federal government directly owns just 3% of the country’s dams, but still plays an important role in dam management. If a non-federally owned dam is located on federal land, for example, it might be a federally-regulated hydropower facility. Or if a dam’s activities might impact federally-regulated waters, federal agencies will have a role to play in providing authorizations.
The three decades between 1950 and 1979 were the heyday of dam construction in the U.S. As cities, industries, and agriculture grew — especially in the West — the U.S. saw an explosion of development that sought to control rivers. Over the following two decades or so, however, construction slowed and a noticeable shift occurred toward greater scrutiny of the impact these structures can have on the environment. Today, there is increased recognition that thousands of dams may have outlived their usefulness, are failing to meet even basic safety standards, or are wreaking havoc on ecosystems. Or all three.
By some estimates, dams block 600,000 miles of river in the U.S. In the West, dams and human-built obstructions have modified the flow of 71% of river miles. The result is nothing short of widespread ecological damage. Dams impede crucial fish passageways, preventing access to spawning and forage habitats; they change the temperature, quality, and composition of waterways, contributing to the ever growing crisis of wetland loss in the U.S.; and they block natural sediment movement, increasing erosion and harming beach areas.
These damages are from coast to coast and everywhere in between. In New England, for instance, nearly 91% of fish habitat is blocked by dams. On the other side of the country in the Columbia River Basin, 130 dams block the river system with related fishery losses estimated in the tens of billions of dollars. When considering just their environmental impacts, dams have fundamentally damaged otherwise healthy river ecosystems that could be providing important flood control, increased recreation opportunities, and crucial wildlife habitat.
Unfortunately, the concerns with dams are not limited to the damage they can do to ecosystems. Given the ever-advancing age of dams on our landscapes, these structures are also becoming increasingly dangerous. An alarming percentage of dams do not meet current safety standards, and communities across the country are faced with the risks associated with dam failure. Over 1,300 dam failures or emergency interventions to prevent failures have been recorded in the U.S. — a problem that is becoming particularly acute as climate change fuels more extreme weather and unprecedented precipitation events.
Our nation’s dam infrastructure was not built for our current climate reality and poses a risk of exacerbating the impacts of climate change.
In North Carolina in 2024, for example, over 40 dams failed or were significantly damaged by the climate-change-charged Hurricane Helene, which caused massive flooding, death, and destruction throughout North Carolina’s mountain communities. In one community, however, an earlier dam removal likely saved the town from increased devastation and property damage from flooding. Communities are coming to acknowledge that with increasing droughts, temperature swings, and extreme storms, our nation’s dam infrastructure was not built for our current climate reality and poses a risk of exacerbating the impacts of climate change.
Dam removals have successfully brought rivers back to life
The prospect of establishing dam removal as a national priority took a back seat when Secretary Babbitt left the Interior Department in 2001, but the effort was revived during the Obama administration’s commitment to ecosystem restoration. Across its agencies, Interior took a hard look at the impacts that climate change was having on our nation’s waterways and, where it made sense, supported community efforts to remove aging dam infrastructure.
In 2016, for example, I got a firsthand look at the work of the Penobscot Indian Tribe to restore the Penobscot River in Maine by removing the Veazie and Great Works Dams and improving fish passage and hydropower generation at other dams that still had a useful purpose. The project improved access to nearly 2,000 miles of river for endangered Atlantic salmon, restored ecological systems that support Maine’s biodiversity, and supported the Penobscot Nation’s culture and traditions.
When I began my third stint at the Interior Department in 2021, the tragedy and complexity of our nation’s aging water infrastructure immediately greeted me again. This time, it was a looming crisis in the Klamath Basin on the border of Oregon and California. The Klamath always loomed large as an issue each time I served at Interior. The region’s history of dam construction and the over-engineering of waterways had left communities dependent on a water dam and delivery system that was not sustainable in the long term. When extreme drought conditions dropped all water levels in 2021, it was once again made clear that the human-built infrastructure system was failing and that changes were necessary.
The Klamath River was once home to the third-largest salmon runs on the Pacific coast of the lower 48 states, but a system of dams built between 1918 and 1962 blocked salmon passageways and damaged the river ecosystem. By the 1990s, there was growing recognition that whatever irrigation and flood control the dam system provided was outweighed by the ecological damage. Communities in the region, including the Tribal Nations that depend on the rivers for their livelihoods, reached important agreements in the early 2000s to remove four dams in the basin and undertake restoration investments throughout the region.
Through nothing short of heroic efforts, those agreements finally culminated with the largest river restoration and dam removal project in U.S. history. In 2024, the fourth and final dam slated for removal under the agreements was taken down. A year later in 2025, the California Department of Fish and Wildlife reported that “scientists are seeing salmon reoccupying just about every corner of their historic habitat,” and sonar equipment recorded the first Chinook salmon moving upstream above the site of the former dams for the first time in 100 years.
Importantly, these dam removal stories — and the stories that we can create in the future — are not just about fish. They are about Tribes who entered into agreements with the U.S. government to protect their fishing rights and ways of life; they are about communities that could be protected from devastating floods by more naturally-flowing river and wetlands systems; and they are about local economies that could benefit from thriving recreational and commercial fisheries.
Importantly, dam removal stories are not just about fish. They are about Tribes who entered into agreements with the U.S. government to protect their fishing rights; they are about communities that could be protected from devastating floods; and they are about local economies that could benefit from thriving fisheries.
We have reached the part in this essay where I must point out what should be obvious: not all dams should be removed. There are many dams and associated water infrastructure systems in the U.S. that are serving important roles. With targeted upgrades, these dams and systems could be made even more resilient and useful. With our nation facing increased energy demands against ever-worsening climate conditions as a result of unchecked fossil fuel emissions, the generation of cleaner energy is imperative, and some existing dams can play an important role in that effort.
It is also true that most Americans live within a mile of a river, meaning virtually all Americans are affected by the health of river ecosystems. Any effort to modernize public land and water management must include a renewed commitment to fully understanding the river infrastructure that exists in the U.S. and assessing how best to remove what’s causing harm and improving what’s worth saving. While I am frankly loathe to call for yet another White House czar or new executive office to lead this charge (for reasons that would take several more essays to explore), the diffuse nature of the federal government’s role in managing dams and their impacts suggests that identifying one entity to help lead this effort may be useful.
A framework for dam removal and river restoration
A meaningful nationwide river restoration initiative should include a federal government-wide assessment of the nation’s entire dam inventory, regardless of ownership type and that incorporates climate change forecasts. The latter is crucial given that climate-fueled extreme weather events, including increasing wild swings between floods and droughts, meaningfully impacts the cost-benefit analysis of any individual dam. Such an assessment should also incorporate appropriate valuations of the ecosystem services that free-flowing, functioning river systems can provide.
Other factors to consider in this assessment: any existing Tribal treaty rights to fishing that have been impeded by dams; relicensing obstacles that threaten the continued financial viability of dams; the failure of alternative approaches to fish passage that might have been tried in an area; and whether there is a threat of species extinction within the foreseeable future if dams in an area remain. Factors that might support dam modernization or at least longer-term approaches to removals could include: financial strength of the current owners and their willingness to invest in upgrades; the viability of dam infrastructure to support hydropower; and the extent of economic reliance on the continued existence of dams.
Federal agencies can only do so much in a go-it-alone approach and, in river restoration in particular, dam removals simply will not happen without community collaboration.
A coordinated federal approach to river restoration would also include an assessment of the multiple grant and technical assistance programs that exist across the federal government and an effort to leverage those sources of support. The so-called “one stop shop” approach could be deployed to provide communities with better information about which agencies and programs might be partners in any effort to meaningfully assess and potentially remove outdated and harmful dams.
One of the greatest obstacles to dam removal is funding, and the federal government should increase both the direct investment in the effort as well as identify additional sources of support that might be used. For example, dam removal efforts can and should be supported through payments from natural resource damage assessments, civil penalties under environmental statutes like the Superfund law and the Clean Water Act, and the creation of mitigation credits during permitting processes for infrastructure projects in a river’s watershed.
Local collaboration is critical
Crucial to the success of this initiative will be a steadfast commitment to the kind of “locally-led problem solving and cooperative decision making” that fellow Ground Shift author Lynn Scarlett calls for in her March 2026 essay. Federal agencies can only do so much in a go-it-alone approach and, in river restoration in particular, dam removals simply will not happen without community collaboration. Secretary Babbitt knew this acutely when he reflected that he did not bring his “sledgehammer to a single dam that was not approved for removal by consensus of the inhabitants of the watershed.” But the federal government can and should play a role in fueling these efforts, especially when so many communities lack the financial and technical resources to move forward.
River restoration generally, and dam removal specifically, only episodically attracts nationwide attention. Recent news cycles would suggest that dams are primarily getting notice now for their potential ability to support increased hydropower. Rising energy costs in many communities in the U.S. — driven in part by growing electricity demand from AI data centers and exacerbated by the current administration’s irrational war on solar and wind energy projects — is certainly real and deserves attention, but the solution is not to prop up aging dams that are destroying ecosystems and threatening community resilience. We need to bring balance and science to these challenges and take this opportunity to assess what’s truly needed and let go of outdated, harmful infrastructure. “Dams do, in fact, outlive their function. When they do, some should go.”
