Nasty!
I recall when I was at Glastonbury one year there was a nasty incident at the Dance Area.
It's a large open space with a number of marquees with Dance DJ's playing sets throughout the days and nights.
As usual, one of the small bowsers arrived that empty the liquid effluent from the portaloos around the site.
Unfortunately the operative, who may have been new, set the hose to 'blow' instead of 'suck' and several hundred dancers were drenched from head to foot in liquid sewage.
Not a nice way to enhance your festival experience!!