Presentation on theme: "Restoration of Columbia River Floodplain Functions to Steigerwald Lake Eric D. Anderson Ridgefield National Wildlife Refuge Complex Ridgefield, WA."— Presentation transcript:
Restoration of Columbia River Floodplain Functions to Steigerwald Lake Eric D. Anderson Ridgefield 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 Lake 20 ft. NVGD 840 acres Columbia River Gibbons Creek Lawton Creek
Changes to Steigerwald Lake Washougal Sewage Plant Port Steigerwald Lake NWR
Feasibility Study Low Gradient Connectivity to 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
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