On our way from Colorado to Moab, we took a scenic byway along the San Miguel and Dolores Rivers. Unexpectedly, we spotted some timbers sticking out from the rock above the San Miguel River.
As it turns out, it was the remains of the Hanging Flume. Between 1883 and 1885, the Lone Tree Mining Company filed several claims along the Dolores River just downstream of its confluence with the San Miguel River. Lone Tree mined it’s properties (including the furthest downstream claim Bancroft) using water diverted with ditches and bedrock flumes from Mesa Creek.
In 1888, the claims were sold to Montrose Placer Mining Company. This larger company needed more water than the systems used by Lone Tree could provide to profitably produce gold via hydraulic mining.
Along the often sheer walls of the San Miguel and Dolores Canyons, traditional methods of flume construction (dirt ditches and trestle supported flume boxes) were not sufficient. The flume needed total drop of just less than 90 feet over its 10 mile course to have the appropriate pressure for mining; falling just 6′ 10″ for each mile. Approximately 7 miles of the flume was constructed along the sheer canyon walls with a flume 6 feet wide and 4 feet deep.
Construction began in 1889 and was finished in 1891. Few records of the flume’s construction appear to exist. The flume began operation in 1891 and moved about 80 million gallons of water from the San Miguel River to the mining site. Yields were approximately 20 to 30 cents of gold per yard with workers moving about 4,000-5,000 yards of earth daily. The gold in the area was very fine and required mercury to recover it.
The Montrose Placer Mining Company went out of business and sold the claims to Vixen Alluvial Gold Mining Company who extended the flume an additional three miles. Still, the flume and mining operation were not profitable (mainly because of the difficulty in recovering gold). The Silver Panic of 1893 crashed metals prices and the flume fell into disuse.
As time passed, pieces of the flume were removed to be used for home building and as timbers in local uranium mines. Additional damage has been caused by erosion of the sandstone and by biological growth. The Hanging Flume was added to the National Register of Historic Places in 1980 and has also been named to Colorado Preservation, Inc’s list of endangered places and to the 2006 World Monuments Fund watch list.
We spotted the flume off of the Y-11 River Rd. that travels south from the former mining town of Uravan. The ruins of the flume are also visible from the Unaweep Tabegauache Scenic Byway (Colorado Highways 141 and 145).
2006 World Monuments Watch List
World Monument’s Fund: Hanging Flume
“121-year-old western Colorado mining flume clings to its secrets.” Denver Post, April 4, 2012 by Nancy Lofholm
“Engineering marvel Unaweep Canyon Hanging Flume to be restored.” Grand Junction Daily Sentinel, April 5, 2012 by Kathy Jordan