by Robert Marcos
The gold fever that brought tens of thousands of miners into Northern California in 1848 led to related discoveries of gold at La Paz in 1862 (before Arizona was a state), and in 1896 on the Klondike River.
Smaller gold deposits – like those in New Mexico’s Ortiz Mountains, had been identified earlier than these but they lacked the massive infrastructure, communications, and population density that was needed to turn small gold deposits into a major excavations. Furthermore, before the signing of the Treaty of Hidalgo, most of the American West was under Mexican rule which made the large-scale migration to the region more difficult.
At La Paz – a full year before Arizona was even a territory – there were 5,000 miners working hundreds of gold claims on both sides of the Colorado River. These miners and the hundreds of workers who supported them were desperate to find a way to transport people and the tons of supplies needed at these remote sites: which included the small Arizona towns of Quartzsite, Ehrenberg, and Bouse.
Steamboats came to the rescue
The first steam-powered paddleboat to navigate the Colorado River was the Uncle Sam. Designed by Domingo Marcucci and built in San Francisco, the 65-foot-long, side-wheel paddle steamer was shipped in pieces to Port Isabel on the river’s delta. It was reassembled and launched in November 1852 to carry military supplies 120 miles upstream to Fort Yuma. Driven by a tiny 20-horsepower steam engine, the Uncle Sam struggled to make headway against the strong currents (going in the opposite direction), and it took 15 long days in order to complete its first voyage.1
The Cocopah – the River’s Largest Steamboat
Cocopah was the largest ship used during the Colorado River steamboat era. The sternwheel paddle steamer was built for $35,000 by the George A. Johnson & Company in San Francisco and it was the fifth steamboat to work along the Colorado River. Cocopah’s sturdy engine could carry 100 tons of cargo against the strongest of river currents. The Cocopah was 140 feet long, 29 feet wide, and had a (very shallow) draft of 19 inches, even fully loaded – which was perfect for navigating over shallow water and sandbars.
After being assembled the at Gridiron Landing in Sonora, Cocopah was launched in August of 1859 and captained by David C. Robinson – an experienced captain who formerly steered the steamboat Explorer in a Colorado River voyage. The Cocopah continued its travels along the Colorado River until 1867. Afterward the Cocopah was moved onshore and used to house workers at Port Isabel, near the point where the Colorado River meets the Sea of Cortez.2
Steamship Operations Brought to a Sudden End by the Railroad
The arrival of the Southern Pacific Railroad in Yuma, Arizona, in 1877 dealt a fatal blow to the Colorado River steamboat era. The railroad broke the riverboats’ monopoly on the transportation of cargo and passengers to regions that had previously been hard to reach. Trains moved goods across the desert in a fraction of the time and at significantly lower cost than the steamboats. As rail lines expanded across the Southwest over the following decades, they systematically bypassed the river, rendering the expensive process of shipping supplies upstream entirely obsolete.3
