Houston is a big city, in more ways than one.
The 10,062 square miles of the Houston Metropolitan Area is larger than the entire state of New Jersey. By the next Census in 2020, Houston will be the third-largest city in the US, surpassing Chicago. Houston is also the biggest city in the biggest (contiguous) state, which can often lead to big disasters.
The deadliest storm on record in the US occurred before such storms even had names. The hurricane that struck Galveston in 1900 killed more than 8,000 people, against a population of just under 50,000 at the time. The storm and others that followed prompted the construction of jetties and a seawall along Galveston’s shoreline.
While Harvey broke records for most rainfall from a tropical system, the highest rainfall in a 24-hour period in US history occurred in Alvin in 1979. During Tropical Storm Claudette, the suburb south of Houston saw 42 inches of rain in 24 hours.
The most expensive tropical storm also occurred in Houston. Tropical Storm Allison dumped more than three feet of rain onto Houston and the surrounding areas in June 2001. The storm caused more than $5 billion in damages.
Of course, Hurricane Harvey rewrote the record book on rainfall. In Friendswood, just south of Houston, rain gauges recorded 56 inches in less than three days. The next day, the storm moved over Beaumont, where it dumped an astonishing 65 inches of rain and overwhelmed the city’s water treatment system.
The staggering scale of rainfall in Houston isn’t limited to tropical systems. The “Tax Day Flood” of 2016 dropped 17 inches of rain and contributed to eight fatalities. The “Memorial Day Flood” of 2015 dropped 12 inches of rain in only 10 hours.
As long as millions of people choose to live in a swamp with the drainage capabilities of a dinner plate, Houston residents can expect more rains, and more floods, in the future.