How should I save my hair from dreading/splitting at a 4 day 100 degree music festival with no showers?

I have long thick blonde hair. I wash it daily even though it never gets oily, it just gets very dry and tangled if I do not wash it for a while. And Sasquatch is at the Gorge which is very dry and hot. Does anyone have any ideas to save it from becoming a dreaded hairball?