Water horses

We've been letting the horses graze all around the house to keep the lawn mowed down. There is a steep slope to the creek we use and, low and behold, all three horses decided the grass was tastier down there and took to hanging out creekside.
I thought Gracie, the Quarter horse, would go down. She's an experienced trail horse. Hank is pretty sure footed and he waded into the creek pretty deeply, actually causing me to worry he would just mosey on down the creek and then I'd be in a pickle. He was actually the only horse to get into the water. Hayes said Hank loved the creek grass. She is a cuckoo-bird for getting in this deep! It was 70 degrees out, but that's still cold water.
What surprised me most was Spellbound, our 31 year old Thoroughbred, going down there.
Once everyone had his or her fill, they took a run up the slope to much the regular grass.