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.

"Camp Mystic is grieving the loss of 27 campers and counselors following the catastrophic flooding on the Guadalupe river," started the statement on the website of Camp Mystic for Girls. "Our hearts are broken alongside our families that are enduring this unimaginable tragedy. We are praying for them constantly."