The rivers etching the terrain are a beloved feature of the rapidly growing region. But last week’s flooding was an agonizing reminder of the dangers they pose.

When storms roll in, water rushes downhill fast, gaining speed and force as it moves — often with deadly results.

Five people died in Central Texas floods in October, and then the rain kept coming for the next two months. Catastrophic flooding devastated the Hill Country, and statewide at least 180 Texans died because of the countless overflowing rivers and creeks.