With more than 170 still missing, communities must reconcile how to pick up the pieces around a waterway that remains both a wellspring and a looming menace.

The Guadalupe River has a history of deadly flooding. Here is a look over the decades. (AP video Marshall Ritzel/Albee Zhang)

In what experts call "Flash Flood Alley," the terrain reacts quickly to rainfall steep slopes, rocky ground, and narrow riverbeds leave little time for warning.

Over 100 people have died after heavy rain pounded Kerr County, Texas, early Friday, leading to "catastrophic" flooding, the sheriff said.

Texas Gov. Greg Abbott says more than 160 people are believed to be still missing days after flash floods killed more than 100 people across central Texas

Officials in flood-stricken central Texas on Wednesday again deflected mounting questions about whether they could have done more to warn people ahead of devastating flash flooding that killed at least 119 people on July 4.