When a catastrophic earthquake struck San Francisco in the early hours of April 18, 1906, it ruptured gas mains all over the city. Soon, fires were consuming the quake-damaged buildings, block by block. Over the course of three days, 500 city blocks were demolished by fire, burning virtually unchecked.

One of the problems was San Francisco's meagre emergency water system. Although the city was surrounded by water, officials had no way of getting that water further inland — a problem city officials had long been aware of but had been slow to remedy.