Are you talking about Fish Creek Camp or Fish Creek Saddle?
If FC Camp- I was just there about a week ago. There was plenty of water in the creek/ stream either above or slightly below the camp areas (see my post for a map of the lower water source).
Trail report: https://sgwa.org/forums/topic/fish-creek-camp-5-29-2020/
If FC Saddle, there was water about .25 miles down on the right side of the valley/ drainage when we were there a few weeks ago. Otherwise, you could walk the 1 mile or so down to Lodgepole Spring where there was also water.
My trail report from then: https://sgwa.org/forums/topic/fish-creek-trailhead-to-fish-creek-saddle-5-15-16/