There’s a handfull rustic, built with love outdoor shower cabins with hot and cold water you can use as our guests and staff at the festival area, right next to the camping ground. You may need to be patient during rush times though. Besides the shower cabins there also are washbasins you can use for your morning and evening hygiene.
For your needs there are some toilet cabins and also a pond you can use as urinal (no joke!) right next to the camping ground.
(At this point we clearly DO NOT recommend bathing in that pond!)
Also there are toilets inside one of the buildings at the festival area.