Plans to develop a flood monitoring system in the Texas county hit hardest by deadly floods were scheduled to begin only a few weeks later.

At least 120 people have been found dead since heavy rainfall overwhelmed the river and flowed through homes and youth camps in the early morning hours of July 4. Ninety-six of those killed were in the hardest-hit county in central Texas, Kerr County, where the toll includes at least 36 children.

Rain rushing to the Guadalupe took it from a depth of less than 8 feet to 37.5 feet, a deluge with as much volume as an aircraft carrier over five minutes.

Heavy rainfall has overwhelmed multiple low water crossings and areas along the Guadalupe River, local authorities reported.

Flash flooding is common enough around the crescent-shaped region from Dallas through the Hill Country, the area earned the nickname "Flash Flood Alley."

Officials in Kerr County, Texas — where 27 campers and counselors at a Christian summer camp were killed in catastrophic flooding — had discussed installing a flood warning system

Over the last decade, an array of local and state agencies have missed opportunities to fund a flood warning system intended to avert the type of disaster that swept away dozens of youth campers and others in Kerr County,

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.

Here's what to know about the deadly flooding, the colossal weather system that drove it and ongoing efforts to identify victims.