In 1987, sudden and intense rainfall caused the river to surge at an unprecedented rate in mid-July, leading to a tragedy that killed 10 campers at Pot O' Gold Christian Camp, a summer camp near Comfort, Texas. The campers drowned when their bus attempted to evacuate them and was overtaken by floodwater.

Growing up near the Guadalupe River in Kerrville, Texas, could sometimes feel like living near a volcano. I was born two blocks away from the gorgeous river that flows from the Hill Country to the Gulf of Mexico, just one year before the devastating and deadly 1987 flash flood, often described around town as the “big one.”

Search efforts continue for the dozens of people still missing after Friday's floods, as questions swirl over what went wrong. Here's what we know so far.