More than a million acres of US tribal lands submerged by dams: study

The construction of dams across the U.S. has resulted in the flooding of a Rhode Island-sized swath of tribal lands, a new study has found.

Dams have inundated more than 1.13 million acres of these lands, raising concerns about threats to flora and fauna, cultural heritage and livelihoods, according to the study, published on Wednesday in Environmental Research Letters.

“The disruption of aquatic and terrestrial ecosystems not only devastates natural resources but also destroys culturally significant sites,” lead author Heather Randell, an assistant professor of rural sociology and demography at Penn State University, said in a statement.

“The impact on local communities’ livelihoods and displacement from their ancestral lands is equally severe,” Randell added.

While dams have played a significant role in fueling land deprivation for Native populations, researchers had not previously quantified the magnitude of that loss, the study authors explained.

Ever since European settlers arrived some 500 years ago, tribal nations have endured land dispossession — including the establishment of federal reservations and the removal of tribes to “Indian Territory,” or modern-day Oklahoma, the researchers noted. 

To gain a clearer picture as to just how much dam-driven loss has occurred, the authors considered geospatial data from federal Indian reservations and the Oklahoma Tribal Statistical Areas, U.S. Census delineated regions that formerly had reservations in Oklahoma.

After overlaying this information with the locations of about 7,900 dams in the continental U.S., they estimated that 139 dams have submerged more than 619,000 acres of land on 56 federal reservations.

Meanwhile, they observed that about 287 dams have inundated more than 511,000 acres of land on 19 Oklahoma Tribal Statistical Areas.

Taken together, the total flooding likely amounts to an area larger than Great Smokey Mountains National Park, Grand Teton National Park and Rocky Mountain National Park combined, according to the study.

Despite this enormous loss, the authors identified ways to make positive change — pointing to the Biden administration’s bipartisan infrastructure law, which includes funding to address risks to dam function.

Dams that affect tribal land, they contended, should be prioritized for removal.

In situations where removal is not viable, one alternative could involve granting a tribe ownership over a dam, which would enable the community officials to manage the resource “in alignment with their interests and values,” according to the study.

Another option could include providing funds for repairs and improvements of the dam, particularly if it is being actively used for flood control, the authors noted.

“In the wake of recent federal legislation addressing aging infrastructure in the United States, it is important to prioritize removing dams that have flooded tribal land,” Randell said.

“This is an opportunity to address historical land dispossession and to respect the sovereignty and rights of Indigenous communities,” she added.