Sprague River - Cole Property

Challenges to restoration are never greater than in the Klamath Basin in southern Oregon along the Williamson and Sprague Rivers.  Despite the many contentious issues, good work is beginning to happen thanks to forward-thinking landowners and resource agencies.  USFWS and the local landowner on the Sprague River undertook an ambitious project to eliminate a large cut-off chute that eroded across one of the meanders, leaving a dry oxbow.

These cut-off chutes are commonplace along the Sprague, and tend to steepen the river gradient due to the shorter channel distance.  This, of course, speeds velocity, lowers water surface elevation, causes bed and bank erosion, and contributes to the current abandonment of the historic floodplain.  Many local residents now see this tendency as counter to their interests. Neither agricultural nor fishery interests benefit from the current instability of the Sprague River system.

The project to restore the oxbow meander of the Sprague took place on the Cole property and was constructed in 2006.  The concept was simple, and called for filling the cut-off chute with material excavated from nearby borrow ponds.  The interface with the active river channel was reveted with juniper and rock counterweights to insure stability in flood flows.  Despite an unusually high flood event the following winter, the project survived with only minor damage to one root-wad.  The filled cut-off chute is currently recovering and becoming part of the floodplain once again.

The success of the project led the landowner and USFWS to tackle a second chute nearby.  Survey measurements before and after the project indicate a significant raise in water surface elevation following restoration of the original channel course into the long oxbow meanders.

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Aerial view of a reach of the Sprague River showing multiple cut-off chute channels in various stages of formation.

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Juniper / rock revetment at plug and channel interface.  2008

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Second plug project below Cole residence on Sprague River. 2008

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