In 1870, the number of Chinese in California gradually increased. Chinese laborers accounted for 9% of the state's residents. And also, in 1870, the economy is in a slight depression. The Chinese people who worked in a low pay generated strong resentment from American people. It's because they felt irritated that Chinese people still spoke Chinese and wore Chinese clothes. The racial discrimination produced numerous casualties. That's why u.s. congress resolved Chinese Exclusion in 1882.
They made many row houses, mass transit, and streetcars because of the rapid population increase.