Between Lower South Desert Overlook and the Bentonite Hills (much closer to LSDO), a 4wd road leaves the Hartnet Road and connects to Caineville Road to the north. Less than two miles from Hartnet Road, you find Rockwater Spring (and have to cross it to continue, which may be difficult), where you see these interesting colors as well as a small sandstone grotto with a tiny waterfall (only a few feet high). Still, it's quite surreal to find this out in the desert, and it doesn't seem to be too well-known.
The Hartnet, Utah-- October 2009