Mooney Flat was an important mining and transportation hub in western Nevada County, California, just east of the Yuba County line. It was situated on modern Mooney Flat Road, about 1 mile north of modern Highway 20, at an elevation of about 800 ft.
Mooney Flat lies at the western end of the auriferous channel that runs down the San Juan Ridge. The channel disappears past French Corral and then reappears around Mooney Flat for a few miles, encompassing the communities, from east to west, of Mooney Flat, Sucker Flat, Smartsville and Timbuctoo, Smartsville was the principal town and still exists today. It is often hard to separate the history of Mooney Flat from the history of Smartsville. While the boundary drawn between Nevada County and Yuba County put Smartsville in Yuba County and Mooney Flat in Nevada County, in ensuing years, the Smartsville residents petitioned unsuccessfully to become part of Nevada County.
Early history
Mooney Flat was founded in 1851 and named after Thomas Mooney. Beginning in 1856, the Schmidt (sometimes written Smith) family built a prominent hotel. Originally called the Live Oak Hotel after a tree which grew out front, it is mostly referred to as the Mooney Flat Hotel or Schmidt's Hotel. The town had a store, run initially by Messers Trail and Otis and later by William Westerfield. Mooney Flat did not have a post office, but was served by the post office at Anthony House until it closed in 1906, then by Smartsville.
The town had its own school district and a "fine" schoolhouse. The school district had 40 students in 1866, increasing to 64 students in 1883. The student population then began to decline until the school district was suspended in 1918 then discontinued in 1920 with the students being reassigned to the Pleasant Valley school. Union, January 5, 1866, June 16, 1883, September 9, 1920. It had its own election district with the hotel or the schoolhouse used as polling places. In 1860, 81 votes were cast in the four-way presidential race, with Lincoln receiving 30 votes. In 1880, 40 votes were cast for president but by 1912, the number was down to 11. These numbers suggest a population during its heyday of 2-300.
In 1890, the United States government issued a patent for the land on which Mooney Flat is located to Nevada Superior Court Judge Walling, for "the benefit of the occupants of the Townsite." Why this occurred is not clear; presumably there was a challenge to the ownership of the properties constituting the townsite.
Transportation
Mooney Flat started as an important stop on the stage lines between Marysville and various points in Nevada County including North San Juan, which crossed the Yuba River around Bridgeport. In the 1860s, those lines were extended to reach the mines around Virginia City, Nevada, over what became known as the Henness Pass Road. The Mooney Flat Hotel became an important stop over for travelers and teamsters. By the time it was completed in 1870, it contained three stories. The first floor contained the public rooms and the Schmidts' bedroom. The second floor contained guest bedrooms and a ballroom. The third-floor was essentially a bunkhouse for teamsters, miners and single travellers.
Mining
Hydraulic mining began around Mooney Flat in 1855. It was quite extensive and profitable. The US Commissioner of Mining Statistics opined that: "The country extending from Timbuctoo to Mooney Flat (three miles) is generally conceded to have been the richest in actual returns...of all the hydraulic-mining districts in California up to the present time." The principal companies included the Mooney Flat Hydraulic Mining Company; the Deer Creek Mining Company; the Excelsior Water and Mining Company, and later the Black Swan. The Excelsior also owned over 150 miles of ditches, taking water from Deer Creek and the Yuba River. Around 1879, the Excelsior acquired a generator and installed electric lights at its Mooney Flat diggins. These were the first electric lights used for industrial purposes in the United States and made night time mining possible.