Flooding, one of the top weather-related killers in the United States, claims an average of 90 deaths each year — and more than half of all deaths are caused by people walking or vehicles driving around barriers and into a flooded roadway, according to the National Weather Service.

People can underestimate the force and power of water. A mere six inches of fast-moving floodwater can knock over an adult and it takes rushing water only as high as a cowboy boot, or about 12 inches, to float most vehicles.

Because most flooding deaths are preventable, the National Weather Service initiated a flood safety campaign in Texas 20 years ago in the middle of severe weather season that popularized the now-familiar slogan: “Turn Around, Don’t Drown.”

This life-saving campaign originated in Texas, where Hector Guerrero, a warning coordinating meteorologist at the National Weather Service forecast office in Brownsville, was concerned about the safety of hurricane evacuees from the Texas Gulf Coast who might move to Central Texas.

“When these hurricanes were approaching, they were sending people to evacuate to the deadliest flood alley in the country, which is Austin and San Antonio,” Guerrero said. “And unfortunately, I would hear stories of some of the same people succumbing to the flash floods in their vehicles, while living in this area.”