Changes in flows and floodplain conditions below Corps reservoirs are needed to meet the ecological requirements of native species and communities.  At the same time, the Corps dams must meet specific purposes including flood control, recreation and irrigation.  The challenge is to identify desired flows and floodplain restoration that will meet the combined interests of ecosystem restoration, natural flood storage and other benefits.  The Corps has a Floodplain restoration General Investigations feasibility study which they are conducting in partnership with The Willamette Partnership, Oregon Department of Fish and Wildlife and The Nature Conservancy.  The Army Corps of Engineers and The Willamette Partnership, through the Mid-Willamette Valley Council of Governments, signed a Feasibility Cost-Sharing Agreement in 2004 and initiated the study.  In 2005, The Army Corps of Engineers signed on to The Nature Conservancy’s Sustainable Rivers Project, expanding the partnership to include assessment of ecological flow requirements below Corps facilities.  The purpose of the overall partnership is to assess opportunities to modify existing flow conditions and floodplain features in the Willamette River and its tributaries to restore natural ecological processes, meet habitat and water quality requirements for native species, reduce flood damages and restore natural wetlands.

U.S. Army Corps of Engineers

The Nature Conservancy

The Willamette Partnership

Oregon Department of Fish and Wildlife

Stakeholder Group (approximately 20 federal, state and local entities)

To date, the partnership has accomplished two important tasks: 1) identifying habitat, flow and water quality requirements for a variety of aquatic and floodplain species, and 2) describing and evaluating the current floodplain condition, and comparing it to the historic condition.  These efforts have incorporated extensive, inter-disciplinary expert and stakeholder involvement.  Future work will focus on identifying environmental flow requirements that will restore and maintain river and floodplain habitat and water quality conditions for a variety of target species.  The work will include developing and/or expanding ecological and hydrologic models.  Specific attention will be given to analyzing alternative flow management scenarios, and to evaluating the operation of the Corps facilities.