North Bloomfield Mining and Gravel Company

What this company sent downstream outlasted what it took out. Gravel washed off these hills raised the beds of the Yuba and the Feather, buried orchards and towns in the Sacramento Valley, and shoaled navigation as far as the bay; the sediment is still moving through the system a century and a half later. So is the mercury, poured into the sluices by the ton to catch fine gold and never recovered. The drainage tunnel alone ran seven thousand eight hundred feet.

What the plaque says

This was a major hydraulic operation in California. Its vast system of canals and flumes using a drainage tunnel 7800 feet long was termed a feat of engineering skill. It was the principal defendant in an anti-debris lawsuit settled by the Sawyer decision in 1884. Judge Lorenzo Sawyer's famous decision created control that virtually ended hydraulic mining in California.

Where it stands

Worth the stop nearby

• Malakoff Diggins State Historic Park — 0.5 mi
  A canyon washed out of a mountain by water cannon, and the lawsuit that ended hydraulic mining.
• Nevada City — 9.2 mi
  Gaslamps, brick storefronts, and the Nisenan who are still fighting to be recognized on their own ground.
• Empire Mine State Historic Park — 14 mi
  The oldest, deepest, richest hard-rock gold mine in California, with 367 miles of flooded tunnels underneath.

More markers nearby

• South Yuba Canal Office — 9.2 mi
• National Hotel — 9.2 mi
• Nevada Theatre — 9.3 mi
• First Manufacturing Site of the Pelton Wheel — 9.3 mi