I've not heard of any real time data for water quality. The three places I would start my search would be the U. of Colorado Boulder, Denver Water Authority, and the Greenway Foundation. They are the ones that have really cleaned up the river and have studied it. Since the late 60's / mid 70's the water quality in Denver has cleaned up 2000%. What was close to being a superfund site is now a healthy happy river. Just looking at all the birds and wide life is amazing.
I think many people are so used to seeing trash or cups in the river and thinking that it's dirty. They forget what industry can do to a river. I'm from the East coast- so, moving out here I can't believe how clean the rivers are. Many folks out here just take it for granite. Lake Erie caught on fire, massive fish kills on several rivers down stream of paper plants, no living things in the rivers because of AMD, and toxic/ radioactive materials being dumped in the rivers by large companies- were all not uncommon.
Clean mountain streams are only that way because no one lives around them. For the size of the population, the amount of large industry, and the daily usage of the river the Platte is very clean. It has a lot to do with the change in environmental awareness, Clean Water Act, and the organizations like the Greenway Foundation. That takes a stance and does something about it.
Sorry for the rant, but I just can't stand it when someone makes a general statement about something they read on the net. Because, you know the readers are only going to grab on to one or two lines and remember it for a lifetime as fact.
Thanks for understanding.
I love to dance, but who needs the music- It throws me off.