With riches derived from Nevada's Comstock Lode,:237 he became one of the richest and most powerful men in California. He founded the Bank of California and was known for having a nothing-is-impossible attitude.
His dream was the construction of the Palace Hotel in San Francisco, California at the corner of New Montgomery and Market. He spent $5M on its construction, draining his banking empire in the process. John Painter Gaynor was the architect and engineer. It opened on October 2, 1875. The hotel had early elevators or "rising rooms" and electric call buttons in the rooms. The hotel survived the 1906 earthquake, but was destroyed in the fire that followed. It was rebuilt and reopened in 1909. There is still a Ralston Room in the hotel off the main corridor to the left.
In 1871, following a severe drought in California, he initiated work on the surveying for an irrigation scheme in the San Joaquin Valley, and his lobbying was successful in securing the passage through Congress in 1873 of an Act to set up a Water Commission to advise on the irrigation of California.
In 1875, his financial empire collapsed as a result of the combination of the expense of building the Palace Hotel, the failure of his attempt to buy and then resell the Spring Valley Water Company, the after-effects of the Panic of 1873, and a crash in the stock value of the Bank of California. The crash occurred just weeks before the opening of the Palace Hotel.:188-191
The day after the collapse, his body was found in the San Francisco Bay. He was the victim of either a stroke during his regular swim or suicide.:190 About 50,000 people were said to have watched his funeral procession, and 8,000 of his friends were said by Robert Brereton to have attended the public meeting held in Union Hall on September 8, 1875 to express the community's loss. His partner, U.S. Senator William Sharon, acquired many of his assets, including the Palace Hotel and Ralston Hall.
Ralston Avenue is one of the principal roads in Belmont, California. Ralston Street in Reno is named for William Ralston. There are Ralston Avenue exits from both Highway 92 and Highway 101. Ralston Middle School, Ralston Hall, and the William Chapman Ralston Award are all named for him. A small mining town in southwest New Mexico was named Ralston City in honor of William Ralston, its largest investor, but has since been renamed Shakespeare. The town of Modesto was to be named for Ralston; he declined, however, and it was called Modesto as one of the Spanish-speaking workers at the naming ceremony for that town said he was "muy modesto" or very modest. Modesto is home to Ralston Tower, an 11-floor building for the elderly. It is the second-tallest building in the city.
Ralston was portrayed by Ronald W. Reagan in a 1965 episode of Death Valley Days, "Raid on the San Francisco Mint." The episode dramatizes an 1869 event in which Ralston gets the head of the mint drunk in order to persuade him to authorize an exchange of bullion for coins. Vaughn Taylor was cast as financier and adventurer Asbury Harpending.