Historical Influences

GOLD!  Discoveries in the late 1840s marked the start of drastic changes in the Trinity River and its watershed.  Small –scale placer mining, like panning and sluicing, was mostly replaced by more efficient hydraulic and dredger mining by the early 1900s and continued through the 1950s.


  • 1828  Trapper Jedediah Smith records his travels along the Trinity River
  • 1848  Major Pierson B. Reading discovers gold at Readings Bar (near Douglas City)
  • 1849  Gold rush begins
  • 1851  Weaverville established as a thriving community
  • 1853  Chinese miners begin arriving
  • 1861-62  Large flood washes away camps and many abandon mining activities
  • 1880s  The famous outlaw Black Bart robs stagecoaches and banks in the area
  • 1898-1958  Gold dredges extensively work many reaches of the Trinity River
  • 1907  Trinity Forest Reserve proclaimed (present day Shasta-Trinity National Forest)
  • 1956  Construction begins on Trinity Dam

Major Pierson B. Reading discovered gold on the Trinity River near Douglas City in 1848 and within a year, the rich Trinity goldfields became the stuff of legend.  Forty-niners poured into the area and on their heels came farmers, ranchers, shopkeepers, teamsters, and homesteaders.  Settlements like Weaverville and Lewiston sprang up almost overnight and their connection to this major event can still be seen in the architecture along their main streets.  After the gold played out and the prospectors moved on it was the farmers, ranchers and lumbermen who stayed on and became the economic mainstays of the area.

Remnants from the California Gold Rush, in the form of dredger tailings piles, are visible up and down the Trinity River.  Mary Smith was proprietor of the only woman-owned gold operation in all of California.  Her mine was operational from the early 1900’s to the early 1960’s when it was shut down for construction of the Trinity and Lewiston Dams.

Gold Dredger

Gold dredger near Lewiston, 1950

By the 1950s, industrial logging began in earnest.  In sensitive areas of the watershed, such as Grass Valley Creek, highly erodible granitic soils were left unprotected and large volumes of sand washed into the Trinity River (CDFG 1963).

Pre-dam Trinity River upstream of Lewiston.

Pre-dam Trinity River upstream of Lewiston.

Prior to the construction of Trinity and Lewiston Dams, flooding was a major problem along the Trinity River.  During the winter of 1861-62, flooding wiped away most of the camps and communities along the river.  During the 1940-41 winter floods, both abutments to the Lewiston Bridge (built in 1901) were washed away and several buildings were either damaged or destroyed.  On December 22, 1955, peak flows in the river reached an incredible 71,600 cfs, flooding most of downtown Lewiston once again.

Lewiston Old Bridge, 1940

Lewiston Old Bridge, 1940. Photograph by Boni DeCamp.

In 1955, the Trinity River Division of the Central Valley Project was authorized directing the construction of Trinity and Lewiston Dams, the Clear Creek Tunnel, Whiskeytown Dam, and a series of power plants.  Completed in 1964, the Trinity River Division began a decades-long era wherein up to 75-90% of the inflow to Trinity Lake was exported from the Trinity River each year to support farming in the Central and San Joaquin Valleys.