big time if you do it wrong.
I once went to Lake Powell with a huge singles ward in the middle of July. Worst decision ever.
Tons of people in meat market mentality; way too many people to have meaningful interactions with anyone, cars getting stuck in 2 feet of sand, and a temperature hotter than Hades.
Awful trip.
Best way to do Powell is with a small group in September after Labor Day or early October when the water is warm and the big crowds are gone, especially the singles wards.