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.

Texans are reeling from the major flood disaster over the holiday weekend that killed at least 82 people, with another 41 missing. Those numbers are expected to rise as authorities continue searching the affected areas.

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.