Yurok Fisheries Dept, Condor Aviation Launch Aerial Mapping Effort

A low-flying helicopter will be traveling along hundreds of miles of the Klamath River from now until early August as the Yurok Tribe Fisheries Department and Condor Aviation work with project partners to create a detailed three-dimensional map of the river following the historic removal of four dams.

The aerial survey, which began July 15, will cover approximately 257 miles of the Klamath River channel from Lake Ewauna in Oregon to the river’s estuary on the Northern California coast.

The helicopter is equipped with high-resolution remote-sensing instruments designed to collect precise bathymetric data, which measures underwater terrain, and topographic data documenting the surrounding landscape. Researchers will use the information primarily to evaluate how the river is changing in response to the removal of four dams near the California-Oregon border.

“This detailed three-dimensional map of the river corridor will provide invaluable insights into the evolution of the Klamath River ecosystem, as well as help us gain a deeper understanding of the river’s overall health. The data will also guide the development of large-scale restoration projects,” Yurok Fisheries Department Director Barry McCovey said.

Crews from the Yurok and Karuk tribes will also collect data from boats as part of the project.

The work is expected to continue through early August. The Tribe advised residents and visitors not to be alarmed if they see a helicopter flying at low elevations near the river. The aircraft involved in the survey has tail number N1525.

Low-flying helicopters are a familiar sight along the Klamath during wildfire season, when aircraft may dip toward the river to collect water. However, the helicopter involved in this project will be gathering data rather than conducting firefighting operations.

The survey comes as scientists, tribes and restoration partners continue to monitor the Klamath River’s response to the removal of four hydroelectric dams, a project that reopened approximately 400 miles of habitat in the mainstem river and its tributaries, according to the Yurok Tribe.

For more than a century, dams altered the Klamath’s natural flow, water quality and movement of sediment and blocked fish from reaching portions of their historic habitat. The Tribe says those changes contributed to declines in salmon, steelhead, Pacific lamprey and sturgeon populations.

Since the dams were decommissioned, spring and fall Chinook salmon have passed the former dam sites and begun moving into streams in California and Oregon that had previously been inaccessible, according to the Tribe.

The Tribe cautioned that recovery of the Klamath ecosystem will take time and require continued restoration and long-term monitoring. Data gathered during the upcoming survey is expected to help researchers track those changes and plan future restoration projects.

The Yurok Tribe’s aerial data-collection program uses aircraft, drones, LiDAR, aerial imagery and other remote-sensing technology to gather detailed information about rivers, forests, landscapes and wildlife habitat. The data can be used for natural-resource management, restoration and infrastructure planning, as well as to evaluate environmental changes associated with floods, wildfires, drought and other natural processes.

Questions or concerns about the Klamath River mapping project can be directed to [email protected].