The Klamath River is the third largest river flowing into the Pacific Ocean from the continental U.S. The headwaters of the Klamath are located in the Cascade Range in southeastern Oregon and the river flows through northern California to its estuary. Beginning in the 1860s, the flow and water quality of the Klamath started to change due to the building of dams and other water diversions for irrigation.
During the twentieth century, four hydro-electric dams were built, further impacting the ecosystem. Impacts include the altering of the channel bed and the blocking of 420 miles of upstream salmonid habitat, resulting in sharp declines in Klamath fish populations.
In addition to the hydro-electric dams, the U.S. Bureau of Reclamation (USBR) operates the Klamath Irrigation Project, providing water to irrigation districts in Oregon and Northern California. USBR operations were also believed to be impacting the fish population and in 2013, a Biological Opinion was published describing the effects of USBR Klamath Project on federally listed fish species. In the Biological Opinion, it was determined that a polychaete worm was the host for a parasite, Ceratomyxa shasta, known to causesignificant mortality in juvenile salmon. As a result, a "real-time fish disease management" system was proposed. This included the release of channel maintenance flows to disrupt polychate habitat decrease the presence of Ceratomyxa shasta and resultant fish disease.
In this project, scientists will study if the managed flows in the river are disturbing the polchaete habitat and reducing the spread of Ceratomyxa shasta. The primary objectives are to spatially assess river corridor conditions and the geomorphic effectiveness of streamflow in an area below Iron Gate Dam, and to relate the flow history to scour and bed mobility conditions necessary to manage fish disease. A secondary objective is to establish sites and methods for repeated monitoring and to develop baseline datasets for interpreting future river response to hydrologic disturbances including channel maintenance flows for fish disease mitigation.
Science Plan
River corridor conditions and the geomorphic effectiveness of flows below Iron Gate Dam will be assessed using field and remote sensing methods that include:
- Determining the grain size of mobile sediment on channel margins using pebble counts and bulk samples
- Mapping changes in vegetation to assess encroachment and scour of channel margins using repeat aerial photography
- Interpreting flow and turbidity time series records collected at USGS gaging stations located below Iron Gate Dam
A fine-scale geomorphic and habitat map will be created to provide a foundational map for planning and implementing future monitoring and interpreting river responses to hydrologic disturbances.
Database of Geomorphic Features, Klamath River, California 2010
Sediment mobility and river corridor assessment for a 140-km segment of the mainstem Klamath River below Iron Gate Dam, CA - vegetation mapping
Below are publications associated with this project.
Sediment mobility and river corridor assessment for a 140-kilometer segment of the main-stem Klamath River below Iron Gate Dam, California
Geomorphic mapping to support river restoration on the Trinity River downstream from Lewiston Dam, California, 1980-2011
Channel Maintenance and Flushing Flows for the Klamath River Below Iron Gate Dam, California
Below are partners associated with this project.
- Overview
The Klamath River is the third largest river flowing into the Pacific Ocean from the continental U.S. The headwaters of the Klamath are located in the Cascade Range in southeastern Oregon and the river flows through northern California to its estuary. Beginning in the 1860s, the flow and water quality of the Klamath started to change due to the building of dams and other water diversions for irrigation.
Location of Klamath River Basin, study reach, principle streams, dams, and hydroelectric facilities, California and Oregon. During the twentieth century, four hydro-electric dams were built, further impacting the ecosystem. Impacts include the altering of the channel bed and the blocking of 420 miles of upstream salmonid habitat, resulting in sharp declines in Klamath fish populations.
In addition to the hydro-electric dams, the U.S. Bureau of Reclamation (USBR) operates the Klamath Irrigation Project, providing water to irrigation districts in Oregon and Northern California. USBR operations were also believed to be impacting the fish population and in 2013, a Biological Opinion was published describing the effects of USBR Klamath Project on federally listed fish species. In the Biological Opinion, it was determined that a polychaete worm was the host for a parasite, Ceratomyxa shasta, known to causesignificant mortality in juvenile salmon. As a result, a "real-time fish disease management" system was proposed. This included the release of channel maintenance flows to disrupt polychate habitat decrease the presence of Ceratomyxa shasta and resultant fish disease.
In this project, scientists will study if the managed flows in the river are disturbing the polchaete habitat and reducing the spread of Ceratomyxa shasta. The primary objectives are to spatially assess river corridor conditions and the geomorphic effectiveness of streamflow in an area below Iron Gate Dam, and to relate the flow history to scour and bed mobility conditions necessary to manage fish disease. A secondary objective is to establish sites and methods for repeated monitoring and to develop baseline datasets for interpreting future river response to hydrologic disturbances including channel maintenance flows for fish disease mitigation.
The distended belly on this juvenile Chinook salmon is a clinical sign of Ceratomyxa shasta infection. Photo courtesy of USFWS. (Public domain.) Science Plan
River corridor conditions and the geomorphic effectiveness of flows below Iron Gate Dam will be assessed using field and remote sensing methods that include:
- Determining the grain size of mobile sediment on channel margins using pebble counts and bulk samples
- Mapping changes in vegetation to assess encroachment and scour of channel margins using repeat aerial photography
- Interpreting flow and turbidity time series records collected at USGS gaging stations located below Iron Gate Dam
A fine-scale geomorphic and habitat map will be created to provide a foundational map for planning and implementing future monitoring and interpreting river responses to hydrologic disturbances.
- Data
Database of Geomorphic Features, Klamath River, California 2010
The USGS, in cooperation with the U.S. Fish and Wildlife Service and the National Fish and Wildlife Foundation, compiled a map of geomorphic features along a 140-km segment of the main stem Klamath River below Iron Gate Dam, CA. Flood disturbance within the study reach is produced by the combined effect of natural flows and reservoir releases. The physical response of the Klamath River to flood diSediment mobility and river corridor assessment for a 140-km segment of the mainstem Klamath River below Iron Gate Dam, CA - vegetation mapping
This report documents river response to hydrologic disturbance along a 140-km segment of the mainstem Klamath River below Iron Gate Dam, CA by assessing fundamental indicators of active sediment transport and dynamic changes in riparian vegetation. A combination of field and remote sensing methods were used to document river response to natural rainfall-runoff events (e.g., 2006 and 2017) and mana - Publications
Below are publications associated with this project.
Sediment mobility and river corridor assessment for a 140-kilometer segment of the main-stem Klamath River below Iron Gate Dam, California
This river corridor assessment documents sediment mobility and river response to flood disturbance along a 140-kilometer segment of the main-stem Klamath River below Iron Gate Dam, California. Field and remote sensing methods were used to assess fundamental indicators of active sediment transport and river response to a combination of natural runoff events and reservoir releases during the study pAuthorsJennifer Curtis, Travis Poitras, Sandra Bond, Kristin ByrdGeomorphic mapping to support river restoration on the Trinity River downstream from Lewiston Dam, California, 1980-2011
Historic land use, dam construction, water storage, and flow diversions in the Trinity River watershed have resulted in downstream geomorphic change, loss of salmonid habitat, and declines in salmonid populations. The USGS in cooperation with the Trinity River Restoration Program, a multi-agency partnership tasked with implementing federally mandated restoration, completed a geomorphic change asseAuthorsJennifer A. Curtis, Timothy M. GuerreroChannel Maintenance and Flushing Flows for the Klamath River Below Iron Gate Dam, California
The Klamath River is a major river in northern California and southern Oregon. Iron Gate Dam divides the river into the two subunits where there is a significant change in utilization of the river. Downstream of Iron Gate Dam, the river is very important for the propagation of salmon. To address concerns relating to substrate conditions in the mainstem Klamath River below Iron Gate Dam, the ArcataAuthorsCristopher L. Holmquist-Johnson, Robert T. Milhous - Partners
Below are partners associated with this project.