This trail is good as an out-and-back from the Mad Creek trailhead, or as a one-way on a longer ride. There are indeed hot springs and pools open year round near the start of this trail, and you can drive there as well.
From the hot springs, pass some picnic spots then negotiate a rocky section of trail with at least one short section that causes many to dismount. The trail steadily gets easier as you descend. You generally hug the creek for the first half of the trail, and then diverge slightly and follow an irrigation ditch until you dump out on a dirt road.
A short jaunt down the road (passing two cattle gates) will get you to the paved road, and a quarter mile down from the Mad Creek trailhead.
This trail can be quite hot on summer days. It melts out quickly in the spring.