Gold rush to today: a timeline of mining on the rivers in the Bay-Delta Plan
Oct. 31, 2026 — Several of the rivers in the State Water Board's updated Bay-Delta Plan run through California's old gold country. A timeline, from state and federal records:
- **Jan. 24, 1848:** James Marshall finds gold at Coloma. - **1852–53:** Hydraulic mining, using water cannon against gravel banks, begins in the Sierra foothills. - **1866:** The North Bloomfield Gravel Mining Co. forms at Malakoff, on the South Yuba watershed. - **1875:** Marysville floods as mining debris raises riverbeds. - **Jan. 7, 1884:** A federal court bars dumping tailings into the Yuba. - **March 1, 1893:** The Caminetti Act creates the California Debris Commission, which may permit hydraulic mining where it does not harm navigation. - **1903–05:** Bucket-line dredging begins near Hammonton, in what became the Yuba Goldfields. - **1906 and 1941:** The commission builds Daguerre Point and Englebright dams to hold back mining debris. - **Oct. 1, 1968:** The last dredge in the Hammonton field shuts down. - **1986:** Congress abolishes the commission. - **2000:** The U.S. Geological Survey reports the region's highest mercury bioaccumulation in the Bear and South Yuba watersheds. - **2009 and 2015:** California temporarily bans suction dredging, then requires water-quality permits; hand panning is exempt. - **Oct. 29, 2026:** The board adopts the Bay-Delta Plan update.
The wall: How many hydraulic mines worked under commission permits, and for how long, is not given. The acreage of dredge tailings is not given.
Tier: Confirmed (based on State Parks, the Office of Historic Preservation, federal statute, the Army Corps of Engineers, USGS, state law, the Oakland Museum and the Online Archive of California)
Sources
- California State Parks, Malakoff Diggins State Historic Park brochure (2013)
- 33 U.S.C. 661 and following (Act of March 1, 1893); Pub. L. 99-662 s.1106 (1986)
- California Office of Historic Preservation, Gold Discovery Site listing
- U.S. Army Corps of Engineers, Sacramento District, Daguerre Point and Englebright dams
- Online Archive of California, Yuba Consolidated Gold Fields records
- Oakland Museum of California, Gold Rush: Hammonton district
- USGS Fact Sheet FS-061-00, Mercury Contamination from Historic Gold Mining in California (2000)
- SB 637 (Ch. 680, Stats. 2015), chaptered text and Legislative Counsel's Digest
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