We dumped at Santa Rita Park a few years ago but I don't remember potable water there. Maybe we just missed it.
If you're looking for a CG before heading into Echo Basin, consider Target Tree CG about 20 miles west of Durango. Some road noise, but not enough to keep us awake and we only have the canvas walls of a PUP to keep the noise out. The placed fills on weekends, but arrive by mid-afternoon on weekdays and you can probably snag a spot. Worst thing about this CG is they have composting toilets. Not much odor out side of them, but inside -- whew!
There's also a campground called Transfer on your way to the basin, all first come, first served. Never been there so can't advise you.
I'd grab a San Juan NF map before heading out as there is private land interspersed with NFS land in many places.
