Ah yes, more success stories for the wag bag solution, "This wasn't the only un-bagged feces I saw but was definitely the biggest eww factor given its proximity to water I'd been drinking from earlier on."
In my opinion, this waste pile is unlikely to break down before winter given it's location behind a rock and the short duration of warm weather left. At 5 ft from the trail, spring runoff could very well carry it into the creek, and where she goes, nobody knows. If it lodges someplace in the creek, it could very well cause localized contamination. The risk may be low, but the consequences seem pretty bad to me. It's hit and miss, or wait - it's too easy, "dip and miss."
Personally, on this heavily used trail, there's only one place where I've felt comfortable not treating the water - from the spring fed runoff on the lower switchbacks because I was out of water on the way down. No problemo.
