Wells Falls is also known as Businessman's Lunch, and is located next to an abandoned hydroelectric plant along Six Mile Creek. Its uppermost section is formed by a dam, which was probably used to divert water into the power plant. The bridge behind and above the dam is part of Giles Street.
After flowing through the relatively level area below the dam, the water continues downward.
The old power plant stands over the water, while being eaten by the forest.
Since I'd had enough of un-level hiking, I didn't go down to the bottom of the falls, but instead returned to my parked car. Near my parking space was the Columbia Street Bridge, which transverses the Six Mile Creek gorge, about a thousand feet (by my rough estimation) downstream of the falls.
For more on Wells Falls, watch this YouTube video.