The parking area at a trailhead known as Gentle Trail serves the upper observation platform for Blackwater Falls. If you head right from the parking area, you’ll see Blackwater Falls. Instead, head left, hike the road back toward the lodge for a few hundred feet and listen for water. When you hear flowing water, you may see a creek. Cross the creek, and head downhill. From there, it’s only a short distance to the top falls. It's a little steep, but a very short hike to the upper fall. There is at least one more, lower down, and the riverbed can be accessed by going down this run.
The upper is a nice little fall, but it's kind of tight to shoot. You'll want to make sure you have a wide angle here.