Restoration of Columbia River Floodplain Functions to

Steigerwald Lake

Eric D. AndersonRidgefield National Wildlife Refuge Complex

Ridgefield, WA

Goals of Proposal

• Conduct a feasibility study to determine alternatives to restore connectivity, hydrology, and floodplain function to Steigerwald Lake and Gibbons Creek.

• Reconnect the habitats of Gibbons Creek, Steigerwald Lake, and the Columbia River to benefit native fish and wildlife populations.

Location of Steigerwald Lake

Portland

Steigerwald Lake NWR

Steigerwald Lake Hydrology

Steigerwald Lake20 ft. NVGD840 acres

Columbia River

Gibbons Creek

Lawton Creek

Changes to Steigerwald Lake

WashougalS

ewag

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lant

Port

Steigerwald Lake NWR

Feasibility Study

Low Gradient Connectivityto Rearing/Spawning Habitat

Improved Stream Habitat:Meanders Replace Channelization

Flood Protection for Adjacent Landowners

Ingress/Egress of Mainstem Salmonids

Reconnect Gibbons Creek to Steigerwald Lake

Improved Wetland Capacity/Hydrology

Proposal Funding for Planning and Construction

• USACE Section 1135 cost-share funds are available up to 75%

• BPA funding represents 25% cost-share

• Other cost-share partners: USFWS, WDFW, WDOE

USACE1135BPA

OtherPartners

Subbasin Habitat Priorities

Bonneville Tributaries Subbasin Stock Summary and Habitat Priorities

• “Reconnect and preserve off-channel and side channel habitat and associated wetlands wherever they occur. Lower Gibbons Creek, Steigerwald Refuge … are priorities.”

Subbasin Habitat Priorities

Conservation of Columbia River Basin Fish Basinwide Recovery Strategy

• Protection and Restoration Strategy: Removal of structures below Bonneville Dam that inhibit the restoration of floodplain habitats

Subbasin Habitat Priorities

The Bonneville Tributaries Subbasin - Limiting Factors Analysis, Washington State Conservation Commission, 2000

• Limited amount of lower gradient habitat for spawning and rearing of salmonids present between Bonneville Dam and Portland.

Subbasin Habitat Priorities

The Columbia River Estuary and The Columbia River Basin Fish and Wildlife

Program Independent Scientific Advisory Board

• Remove dikes in the lower river and upper estuary to restore connections between peripheral floodplains and the river.

Benefits of the Proposal to Salmon

• Removal of barriers and reduced gradient to historic chum habitat• Current salmonid entrapment issues resolved• Coho, steelhead, cutthroat smolts from Gibbons Creek have access to Stiegerwald Lake rearing habitat

Benefits of the Proposal to Salmon

• Smolts from the Columbia River (e.g. fall chinook) have access to LCR rearing habitats in Steigerwald Lake

• Reconnection of up to 420 acres of Columbia River floodplain/rearing habitats