I took microbiology, environmental science, medical lab procedures and chemistry and you can drink your neighbors urine, and live to tell about it (in 99.9% of cases). It is absolutely sterile. Yes, it does act as a fertilizer, but so does that sand shrimp and so does fish urine.
Annnnnd....we aren't talking about 300,000 people all peeing in the river. If 300,000 FISH peed in the river, life wouldn't be pleasant from a fishes point of view, either.
And about that "rock" business....(pardon me while I strap myself into my seat, because I still fall down laughing when I think of this story....)
A bunch of us went to Potholes in early February to trout fish. We all pretty much felt like h***, given the night before. There is nothing to prop a rod up on, as sagebrush was considerably farther up the hillside. One guy, who we nicknamed Indian, went scouting for something to prop up his rod so hwe wouldn't have to hold it. This lake that we're fishing on is 3/4 frozen over, it's about 22 degrees out, and we're in this walled in depression with cliffs all around.
Indian finds this monster slab of a rock on the shoreline to pack back to the area we all have our plunking rods. He bends over, bear hugs it because it's so heavy, and takes about 3 steps. And off the canyon walls we hear this reverberating wail:
"EEEEEEEEWWWWWWWWWWWWWWWWWWWWW!!! EEEEEEEEEEEWWWWWWWWW!!!!!"
Some evil soul did a heavy duty #2 and put that big rock on top of it. Indian had this "stuff" all over his hands, pasted to the chest of his fishing vest and ground into his sleeves.
He proceeded to take a vigourous dunking in ice water.
Ahhhh, Potholes.....the memories!
I have never laughed so hard in my life.....and still do to this day.
diana