Idaho Fish and Game VIDEO: Restoring the Clark Fork Delta

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Extensive bank erosion has occurred to islands and shorelines in the Clark Fork River, located at the confluence of the Clark Fork River and Lake Pend Oreille in North Idaho, resulting in losses of soil, native riparian and wetland vegetation, as well as the quantity and quality of fish and wildlife habitat.

It is estimated that between 12-15 acres are lost annually to the operation of several dams on the watershed, according to Idaho Department Fish and Game.

The majority of the erosion of the delta soils is the result of wave action and water level fluctuations of Lake Pend Oreille due to the operation of the Albeni Falls dam, located on the Pend Oreille River near the Washington/Idaho border.

In addition, about 15–25 percent of all habitat loss in the delta is attributed to the operation of the Cabinet Gorge/Noxon Rapid hydroelectric projects located upstream on the Clark Fork River.

A short documentary film was produced by Scott Rulander and submitted to the University of Idaho Film Festival in October 2017.

The film shows some of the construction efforts completed for a portion of Phase I of the restoration project. The construction began in November 2014, and was completed by March 2015.

Construction efforts included:

  • Island shoreline rock protection completed: Area 3 = 17,600 linear feet and Area 7 = 2,890 linear feet;
  • Over 50,000 tons riprap rock placed in Area 3 and Area 7;
  • 51,000 willows embedded in rock;
  • 330 trees with root-wads embedded into fill/rock;
  • 13 Bendway weirs constructed on Area 3;
  • 40 acres raised on Area 3;
  • A total of 100,549 plants were planted between April and June of 2015;
  • Approximately 20,813 shrubs and trees were planted by volunteers, school groups and IDFG staff;
  • A total of 79,736 emergent plugs were planted by volunteers and two crews from the Northwest Youth Corp;
  • The invasive reed canarygrass was treated with prescribed burn; the grass clumps were also sprayed with systemic herbicides.