FCRPS Tributary Habitat Projects - John Day River Basin, PN Region

Federal Columbia River Power System
Tributary Habitat Program — John Day River Basin

Oxbow Conservation Area Dredge Tailings Rehabilitation Project

The Middle Fork John Day River on the CTWSRO’s Oxbow Conservation area was dredged mined for gold in the early 1940s. Dredging operations left a dredge channel (North Channel) that cut off Granite Boulder Creek and split the flow of the river. The South Channel, which is the natural Middle Fork John Day River, is in an undisturbed floodplain. Since the North Channel was a ditch, it provided very little rearing habitat and took water flow away from the natural channel as well as intercepting cold water from Granite Boulder Creek.

Phase I of the project placed about 400 logs in the South Channel as constructed logjams, and singel log placements to increase habitat complexity in preparation for restoration of full river flows in Phase II.

The Phase II project target was to rehabilitate land forms altered by the gold dredging back to a condition similar to pre-mining disturbance. These actions include:

construction of about 1,000 feet of new channel to reconnect Granite Boulder Creek to the natural Middle Fork River channel,
grading of tailings to rehabilitate topography to an alluvial fan condition and open additional floodplain to the river,
removal of about 3,400 feet of the North Channel ditch,
covering the regraded tailings surfaces with soil,
planting and seeding of the disturbed areas, and
fencing the new channel to maximize plant growth that would otherwise be suppressed by ungulate browse.

Related Documents
03/2010	Oxbow Conservation Area Reach Assessment PDF 10.42 mb
05/2009	Geomorphology and Hydraulic Model Analysis of the Oxbow Conservation Area PDF 20.24 mb
05/2008	Middle Fork and Upper John Day River Tributary Assessments, Grant County, Oregon PDF 15 mb
	Middle Fork John Day Map Atlas PDF 22 mb
	Upper John Day Map Atlas PDF 2.59 mb