Trinity River

Slide 1

The Trinity River is located in northwestern California where it joins the Klamath River and flows into the Pacific Ocean.

Slide 2

Prior to the mid-1800s California Gold Rush, the Trinity River was historically used by Indian tribes for fishing resources and cultural needs. Miners and homesteaders began to migrate from southeastern states in search of new fortunes which created a demand for reliable water sources. As a result, Congress passed the Trinity River Division Act of 1955 to authorize the construction of dams and power plants for irrigation purposes along the river as part of the Central Valley Project (CVP). By 1964, two dams were in place along the Trinity River, Trinity and Lewiston Dams. The CVP diverted water and caused alterations of the river’s natural system leading to controversy over tribe and citizens’ rights to its valuable resources.

Slide 3

Here you can see the changes to the natural system before and after the implementation of the Trinity River Division’s Installations of the dams.

Slide 4

The increased demands of the river negatively impacted salmon and steelhead fish runs, leaving Tribal members without necessary resources for living. American pioneering and settlement eventually led to the popularity of farming practices for economic development. To support a feasible agricultural economy, the CVP enacted the TRD to construct an irrigation infrastructure. The dams rerouted almost 75-90% of the river’s inflow to the Trinity Lake into the now populated Sacramento Valley causing river channel destruction and riparian buffer degradation. Hundreds of tribal members and commercial fishermen became victims to fish shortages and ecosystem damage caused by the project.