Kerr County officials have for years talked about the need for a more robust flash-flood warning system, including sirens that would reach people in places with no cell service. But in the absence of that expensive infrastructure, they adopted IPAWS — which cost them nothing — as a way to alert more people by phone.

An expert highlights a "point of failure" in Kerr County's emergency alerts during the flood. To stream KHOU 11 on your phone, you need the KHOU 11 app. Download the KHOU 11 app