Flash floods surged through in the middle of the night, but many local officials appeared unaware of the unfolding catastrophe, initially leaving people near the river on their own.

As hope for finding survivors dims, questions swirl around whether Camp Mystic's emergency plan was adequate. Texas doesn't approve or keep copies of such plans; camps are required to show only that they have plans in place.

The data also highlights critical risks in other areas along the Guadalupe River in Kerr County, revealing more than twice as many Americans live in flood prone areas than FEMA's maps show.