By the late 1800s, Americans had developed a greater understanding of health issues and were becoming increasingly aware of the dangers associated with the spread of contagious diseases.
Due to over flowing of immigrants, the water became more polluted and insufficient. Therefore, the government activated the sewer system and it was very successful in saving water and clean water.
Tenements are narrow, low-rise apartment buildings–many of them concentrated in the city’s Lower East Side neighborhood were all too often cramped. By 1900, some 2.3 million people (a full two-thirds of New York City’s population) were living in tenement housing.