Concerning news of spring chinook infected with an undiagnosed gill infection have been reported at higher rates than years prior and has the attention of agencies, anglers and those on the river. Although the average rates and the location of these reports have been concerning, some daily rates of reported infections have been alarming and have definitely garnered the attention of regulatory agencies. The evidence of disease is somewhat surprising because upper river temperatures are not exceptionally high. A key differentiating factor hypothesized by fish biologists, may be that the heavy sediment and ash loads from thunderstorms in June may have damaged the gills of the spring chinook that were making their way upriver at that time, stressing them and thus making them vulnerable to disease.

On June 16, The Bureau of Reclamation and the U.S. Department of Agriculture Natural Resources Conservation Service announced 11 projects totaling $6 million to be awarded as part of three Klamath Basin Salmon Restoration grant programs. Four of the 11 aforementioned projects will be administered in the Trinity River watershed. The 4 projects selected will improve aquatic habitat by reducing fine sediment delivery, improving fish passage, and pursuing increases to tributary flows in the dry season in tributaries of the Trinity River.

Photo of the East Weaver Creek Dam provided by Northwest California Resource Conservation &
Development Council.

Thunderstorms and sudden cloudbursts are common in the mountains during the summer, yet following a wildfire, they can have dramatic results. This is especially true after a dry year without significant rainfall. A single downpour can set a mountain stream roaring, sending a puff of suspended sediment downstream to wash into the river below. Usually this passes quickly, leaving little trace. Significant rainfall and subsequent runoff normally occur in fall or winter. However, an unexpectedly intense storm directly following a wildfire in 2022 lead to a natural disaster on the Klamath River.

Photo: A similar thunderstorm cell pushed sediment downstream the North Fork Trinity River in August of 2022. In contrast to the Klamath incident, the Trinity River did not see a major fish kill. Fish biologists believe that this difference is due to the timing of the fires and storm events in each watershed. In the Trinity River instance the fire had been in prior years and in the Klamath River instance the storm event happened on a fire scar in the same year. [Mike Dixon, Reclamation]