How did the gold rush most significantly change San Francisco?

As people moved west the population greatly increased.

The California Gold Rush (1848-1855) began on January 24, 1848, when gold was found by James W. Marshall at Sutter's Mill in Coloma, California. The news of gold brought some 300,000 people to California from the rest of the United States and abroad. The sudden influx of immigration and gold into the money supply reinvigorated the American economy, and California became one of the few American states to go directly to statehood, in the Compromise of 1850. The Gold Rush initiated the California Genocide, with 100,000 Native Californians dying between 1848 and 1868.