Yep! I remenber when we hired out on the D&S John, they still had a stash of waterbags with D&RGW on them aand they issued them until they were all gone. Then they got some with D&SNG. I always used mine, filled it up in Durango and the stream just below Needleton Tank. I still have mine stowed away in the garage.
I don't knwow, but I drank the water from high mountain streams in Colorado fpr years and never got sick. Nowdays it is probably risky.
I Used to fill water cans from the overflow (tank) at Cumbres when I lived in the Chama Bunkhouse. God knows what was in that tank, but I never got sick....now if I drank Chama water from the tap, that was a different story! My bride recieved a very un-pleasant bladder infection after accidently drinking Chama water.