Site information:

North shore of Camanche Reservoir, 1 mi W of County Line Bridge on Lancha Plana Buena Vista Rd, 6.0 mi S of Buena Vista

Directions above from OHP.  Nothing remains of the site, as far as I know.  Approximate site would be

38.230831, -120.905494

Plaque information:

A private plaque commemorating Lancha Plana has been placed at the Camanche Resevoir North Shore Marina, on Camanche Road. 

The marina is private and gated, and likely restricted to operating hours.  A temporart guest pass was obtained to visit the plaque.

38.235150, -120.946116

Plaque text:

In 1848, Mexican Settlers from Sonora, Mexico established a camp on the north back of the Mokelumne River and called it Sonora Bar. At the start of the California Gold Rush miners flocked to the Mokelumne River and set up camps and towns along its mineral-rich banks. Just across the river from Sonora Bar lay the exceedingly rich gravel deposits of Poverty Bar. A ferry was established that carried miners across the river to Poverty Bar and the hard-rock mines of Calaveras County. Eventually the name of the camp was changed from Sonora Bar to Lancha Plana, Spanish for "flat boat," a reference to the ferry.

Lancha Plana reached the height of its prosperity after 1856 when hill and bluff mining largely replaced river mining. In 1858, the town boasted a population of over 1,000 people, enough to support it's own newspaper. The Lancha Plana Dispatch went into circulation on March 3, 1860. By November of that year, the successful newspaper was relocated to Jackson, the Amador County seat, and became the Amador County Dispatch.

Today, what is left of Lancha Plana lays beneath the waters of the East Bay Municipal Utility District's Camanche Reservoir. The modern Lancha Plana Bridge is located near the now inundated town after which it is named. 

Thank you to the East Bay Municipal Utility District for allowing the placement of this commemorative plaque on their property.

Dedicated January 21, 2017 (6022) by the James W. Marshall Chapter 49 of the Ancient and Honorable Order of E Clampus Vitus.

OHP description:

Lancha Plana (Flat Boat) was well settled by 1850 due to the hydraulic mining operations in the extensive gravel beds along the Mokelumne River. The Amador Dispatch newspaper was born here in 1856. Poverty Bar, Camp Opra, Copper Center, and Put's Bar were 'suburbs' of the larger town.

Registered 8/1/1932