That's a bit extreme for me. Although if you ignore the text and just think of the pictures as a creamy warm black mud pit you can play naked in...
Although I'm wondering how much "sewage" he is really in. Those type of treatment plants have pools of progressively-less-shitty sludge, to the point it eventually becomes a mulch/fertilizer that can be sold off in bulk. He could be in a pool of not much more than garden muck.