(http://i941.photobucket.com/albums/ad256/waldoegray/miningflume.jpg)
A flume is an artificial water channel, a gravity chute, used in hydraulic gold mining. A flume many times consisted of a wood box, as in this case.
These workers are rebuilding a 48 foot section of an original 10-mile long hanging flume built in the 1880s along a remote canyon wall near CO-141 in extreme western Colorado.
The original part of the 10-mile long flume is in the upper part of the photo. It took 25 men three years to build the hanging water box.
After the mining company abandoned the flume, "local" people actually walked along the structure stripping the boards for their building purposes.
The ten mile plunge of the water dropped a total of 90 feet at its destination allowing a water pressure that was sufficient to mine gold.
Denver Post, April 14, 2012.
That's very interesting. Thank you for posting it.