More than a million acres of tribal land – an area larger than the state of Rhode Island – have been flooded by dams, compounding centuries of land seizures and forced displacement by settler colonials and the US government, new research has found.
Land has always been central to Indigenous culture, sovereignty and prosperity, while land dispossession has been a mainstay strategy used to divide and disempower communities, by depriving Indigenous people of clean water, traditional food sources, spiritual connections and economic opportunities.
The study, published in the journal Environmental Research Letters, is the first attempt to calculate the amount of land lost by Indigenous Americans due to the construction of dams that re-engineered America’s rivers and lakes to store, divert and control waterways.
By overlaying geospatial data on tribal land boundaries with the reservoirs created by 7,900 major dams, researchers at Penn State and Arizona university found that 1.13m acres of tribal land – an area larger than Great Smoky Mountains national park, Grand Teton national park, and Rocky Mountain national park combined – has been submerged underwater. The true figure is likely significantly higher, as reservoir data for tens of thousands of smaller dams is not available.
Land submerged by dams is in addition to more than 2bn acres – the equivalent of 97% of tribal territory taken through treaties, laws, purchases, violence and coercion since the arrival of colonial settlers more than 500 years ago.
“This is the first study to quantify tribal land flooded by dams, which is an overlooked and additional source of Native land dispossession,” said the lead author Heather Randell, assistant professor of rural sociology and demography at Penn State University. “There was a lot of immediate trauma caused by the flooding and many long term impacts for tribal members that continue today.”
There are more 90,000 6ft or taller dams in the US, of which 2% are megadams rising over 100ft, according to the Army Corps of Engineers’ data. Large, federally-owned dams – such as the Hoover dam which created Lake Mead – proliferated in the mid-20th century during a different climate, with multiple functions such as flood control, electricity generation and diverting water supplies for irrigation.
Dams are not harmless. Previous studies have shown that worldwide as many as 80 million people have been displaced by dams, while an additional 472 million people living downstream have had their family lives and livelihood disrupted – including many Indigenous Americans in Oregon, Oklahoma, Minnesota, the Dakotas and Arizona.
Negative impacts can include flooded homes and farmland, as well as decimated traditional food sources such as salmon populations.
Overall, the study found 139 dams have flooded land on 56 federal reservations, while another 287 dams have flooded land on 19 Oklahoma Tribal Statistical Areas (OTSAs) – locations in present-day Oklahoma that were established for tribes during the era of forced removal.
The land lost varied from dam to dam, but submerged on average 3% of the total reservation. In New York, the Kinzua dam flooded almost one-third of the Allegany Reservation, while the Pick-Sloan Plan – a federal infrastructure project in the Missouri River basin for flood control and economic development – included five large dams that flooded over 350,000 acres on seven reservations in North Dakota, South Dakota and Nebraska.
“In light of recent legislation to address ageing infrastructure in the US, as well as increasing risks to dam function and safety caused by climate change and growing Native land back movement, dams that impact tribal land should be prioritized for removal,” Randell said.
The 2021 Infrastructure Act allocates $800m for dam removal, while another bill, the 21st Century Dams Act, if approved, would provide up to an additional $7.5bn for dam removal.
According to Randell, consulting tribal communities – which was rarely done before most dams were constructed – is key, and where removal is not a preferred or viable option, alternatives could include tribal ownership or funding for repairs and improvements.
The Department of the Interior declined to comment.