The San Antonio River floods on this day in 1921, killing 51 people and causing millions of dollars in damages. The flood was caused by some of the heaviest rainfall ever recorded in Texas.
The San Antonio River winds through southwest Texas, an area that is generally dry. However, on September 7, a storm stalled over the town of Taylor and dumped an astounding 23.11 inches of rain on the area in less than a day. It was the heaviest single day of rainfall in the state to that time.
The immense amount of rain quickly overwhelmed the river. Taylor is located 30 miles upstream from San Antonio, so the resulting flash flood went barreling toward the city. Most of the victims were trapped in their cars by the surprise flood and drowned. Five to 10 feet of water submerged the city's streets, delaying an evacuation.
The city was under water for nearly a week following the flood. The flood was responsible for at least $5 million in damages in the then-small city. In the aftermath, San Antonio embarked on a 10-year overhaul of its levee system.