Undamming the Klamath

Undamming the Klamath

Between October 2023 and October 2024, the four dams comprising the Klamath Hydroelectric Project were taken down. Gates opened, dams were blasted apart, reservoir drawdown began. The result, at first, was a rush of sediment that muddied the waters of the Klamath River. As the river flowed toward the Pacific Ocean, water levels lowered, exposing previously submerged land to sunlight. In this time series, you can see the Klamath turn murky brown with sediment, then watch as its reservoirs drain into a thin stream.

 

The first Klamath dams were built in the early 1900s, disrupting a critical migration route for salmon in Oregon and California. The removal of the dams opens more than 400 miles of salmon habitat. In October 2024, as the last obstacles were cleared from the river, the Oregon Department of Fish and Wildlife identified the first fall-run of Chinook salmon since 1912. By spring 2025, flowers could be seen blooming on Klamath’s riverbanks. Local managers have been seeding the newly exposed land with native vegetation with the goal of improving soil quality and stability.

Change in NDVI from 2024 to 2025 in the Klamath River.
Change in NDVI from 2024 to 2025 in the Klamath River. NDVI represents the health and density of vegetation. Areas around the Klamath are bright green, depicting the growth in vegetation between 2024 and 2025 in the wake of the reservoir drawdown.

Time series by Ross Walter, using data from Landsat 8 and 9. NDVI image by Allison Nussbaum. Caption by Madeleine Gregory. 

This story was originally published on February 21, 2025. It was updated May 29, 2025 to reflect new data and to include the image of NDVI change. 

Post Last Updated on May 29, 2025
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