Picacho (on the lower Colorado River, California side; historically linked to Arizona Territory) was a gold-mining settlement and steamboat landing that flourished from the 1860s into the early 20th century.
Founding and Early History
The site lies along the Colorado River roughly 48 miles (77 km) upstream from Arizona City/Yuma (then in Arizona Territory), opposite Arizona-side landings such as Eureka and Williamsport. It takes its name from nearby Picacho Peak (Spanish for “peak” or “big peak”; earlier Anglo references sometimes called it Chimney Peak). The original townsite is now submerged under Imperial Reservoir; remaining mill ruins lie above the waterline within present-day Picacho State Recreation Area (California Historical Landmark #193).
Spanish explorers and prospectors likely worked placer gold in the area as early as around 1780. Sustained American-era activity began after the California Gold Rush and the establishment of Fort Yuma. In spring 1862, Sonora-born prospector José María Mendivil, traveling north from Yuma toward the La Paz gold discoveries, found placer gold in the washes near Picacho Peak. He returned later, homesteaded riverfront land, and laid out a townsite initially called Rio (soon renamed Picacho). Streets were named after his daughters. Early methods included dry-placering (shaking gravel on blankets to concentrate heavier gold particles).
Mining remained sporadic and small-scale through the 1860s–mid-1870s. Hard-rock development accelerated in the late 1870s. In 1878 (some accounts note an earlier arrastra around 1873), Yuma businessman David Neahr built a substantial 10- to 15-stamp mill of hand-cut local rhyolite stone on a bluff overlooking the river. He chartered the sternwheeler Cocopah to deliver about 30 tons of machinery. The mill processed ore from Mendivil’s nearby Apache claim and other properties; ore was packed by mule from the hills. Neahr expanded but later went bankrupt after embezzlement. Subsequent operators, including Dr. DeWitt C. Jayne, continued work; by the early 1880s reports noted thousands of tons of ore averaging around $21 per ton.
A larger boom came in the 1890s–early 1900s under promoter Stephen A. Dorsey and the California King Gold Mines Company. A large (reported ~450-ton capacity) stamp mill was erected, along with a narrow-gauge railroad (about 4–5 miles) from the mines near the peak to the riverside mill. Peak employment reached around 700 miners; the town’s population is commonly cited at up to 2,500 at its height, with stores, schools, saloons, and supporting industries (woodcutting for steamboat fuel, ranching, stage work). Gold production was strongest around 1904–1906.
Decline followed from depleting/lower-grade ore, mill accidents, rising costs, and especially the loss of cheap river transport after construction of Laguna Dam (completed 1909), which blocked upstream steamboat navigation. The mill was eventually moved inland; operations largely ceased around 1910. The townsite was flooded by Imperial Reservoir in the late 1930s.
Role in the Colorado River Steamship Industry
Picacho served as a regular steamboat landing from about 1862 to 1910, part of the network supporting mining, military posts (Fort Yuma and others), and settlements along the lower Colorado. Shallow-draft sternwheelers (and earlier sidewheelers) of George A. Johnson & Company and later the Colorado Steam Navigation Company (reorganized 1869) dominated the trade. They carried mining machinery, supplies, passengers, and wood (often cut by local labor in desert washes), and took out ore or concentrates for further shipment via the Gulf of California and coastal vessels to San Francisco or other ports. Barges were frequently towed for extra capacity. The landing sat in a cottonwood-and-willow grove with adobes and huts; it was a practical stop roughly midway in the lower-river run above Yuma.
Steam navigation on the Colorado began in the early 1850s primarily to supply Fort Yuma more cheaply than overland routes from San Diego or San Francisco. Regular service expanded with mining booms (La Paz, Castle Dome, Eureka, Eldorado Canyon, and Picacho itself). The Southern Pacific Railroad’s arrival at Yuma in 1877 reduced through traffic, but local and upper-river freight (including Picacho) continued until the Laguna Dam ended commercial navigation upstream of Yuma.
Ships and landings associated with Picacho include vessels of the dominant fleets that routinely called at lower- and mid-river points (Castle Dome, Eureka/Williamsport, Picacho, Norton’s Landing, Clip, Ehrenberg/La Paz, and farther north). Documented or strongly indicated connections include:
- Cocopah (Cocopah I, sternwheeler launched 1859; or the later Cocopah II of 1867): Chartered specifically to deliver mill machinery to Picacho in 1878; the class of vessel regularly served the lower river.
- Mohave / Mohave I (sternwheeler, 1864–1875) and Mohave II (1876–c. 1900): Standard workhorses on routes that explicitly included Picacho among mid-river stops.
- Other Colorado Steam Navigation Company vessels such as Colorado (various), Gila, Nina Tilden, and supporting barges that worked the same corridor of landings.
- Later/smaller craft in the declining years (e.g., light freighters operating into the early 1900s) continued intermittent service until the dam closed the route.
Picacho’s steamboat era thus tied a remote desert mining district directly into the commercial and military logistics of Arizona Territory and the broader Southwest until railroads and dams rendered river transport obsolete. The site’s remaining mill ruins and the surrounding recreation area preserve tangible evidence of this chapter of Colorado River history.
