AUSTIN, Texas — You've likely seen the video of Austin police officers rescuing three young women and their dog from rising floodwaters in southwest Austin earlier this month.
What you don't see in the video, however, are the low water-crossing arms down like they were supposed to, warning drivers not to go over Old Bee Caves Road just off Highway 290.
As KVUE discovered, there was a malfunction that delayed those crossing arms from going down.
If you drive over the low water crossing on Old Bee Caves Road and look over the side, you'll see a metal piece of equipment sitting just a few inches above Williamson Creek called a "float switch." The float switch "kind of works like your toilet bowl does," said Scott Prinsen, project manager with Austin's Flood Warning System.
"When there's a little lever inside that reaches a certain point, that will trigger our lights to come on at those intersections."
However, on the night of heavy rains on May 3, the water rose so quickly "an entire May's worth of rain fell in two hours," said Prinsen.
That triggered flooding upstream in Williamson Creek in the Dripping Springs area, forcing large amounts of debris to quickly pile up and rush downstream, right past the Old Bee Caves Road crossing.
"We had everything from a shopping cart to a very large boulder to very large tree trunks," explained Prinsen.
That debris slammed into the float switch, severely damaging it according to Prinsen.
"The effect was those arms didn't go down as quickly as we would like them to."
So the road stayed open, and that's when the three young women drove over it, getting stranded in their car by the rising floodwater.
They were nearly swept away before several Austin police officers rushed over to help rescue them.
According to the APD officers, Austin firefighters manually lowered the crossing arms after the rescue.
Prinsen says the city's crews fixed the equipment and removed debris the next morning. He warns drivers to never go over a road with water on it, no matter how high or low the water appears.
"Just know when you're around some of these crossings and we have rain, as we have seen, they can go from dry to flooded in the span of about 10 to 15 minutes," warned Prinsen.
He also noted their flood gauge that night, on May 3, registered the second-highest recorded level ever for Williamson Creek, at just over 11 feet, "so you can imagine the amount of water running down Williamson Creek headed toward that particular water crossing at that particular time."
Check atxfloods.com for low water crossing closures during storms.
PEOPLE ARE ALSO READING: