Over the past few weeks, we have taken an in-depth look two of the four interrelated core values that guide the vision and master plan: Public Access and Historic and Cultural Interpretation. This week, we continue the series by exploring Healthy Habitat.
Historically, Willamette Falls was surrounded by plants dependent upon the microclimates associated with the waterfall mist. Today, many rare plants thrive on river islands in the Willamette Narrows and along Canemah Bluff. The area also is important for water quality and the species that depend on clean, healthy water. Much of the naturally steep shoreline has been modified by years of development and industrial uses and is now lined with fill, pipes, and other structures. Five outfalls and three industrial tailraces (drainage channels) emerge at the shoreline.
Restoration actions will be developed to increase the presence and condition of native habitats and improve water quality on the site. The riverbank south of the site is also part of this project and offers additional opportunities for habitat restoration. Among the opportunities for maintenance, restoration, protection and enhancement of a healthy habitat are:
- Aquatic Habitat – salmon, steelhead and lamprey are known to pass through this part of the river, but don’t currently have adequate resting habitat.
- Shorebirds – shorebirds use the falls, but access to rocky outcroppings is limited compared to the historical extents.
- Basalt Geology – the site is mostly underlain with basalt bedrock similar to the falls, with some soils that could support new vegetation
- Floodplain – flood events, including the 1964 and 1996 floods inundated portions of the site. The river below the falls is tidally influenced, with an average change in water level of approximately 3-4 feet, twice a day.
The master plan identifies areas along the riverbank where habitat enhancements and riparian bank restoration could occur. The general principle advanced by the master plan is for the riverbank to re-establish a rough edge and to meander in a pattern more indicative of its pre-industrial state, in order to allow more opportunities for fish to rest and riparian vegetation to thrive. Restoration and enhancement opportunities for improving fish and wildlife habitat can also provide improvements for water resources, including stormwater treatment and water quality. Specific habitat restoration targets include:
- Riparian Habitat: restoring native trees and shrubs along river; protecting and restoring rocky outcrops by removing buildings and structures; providing important habitat for migratory birds and other wildlife species; and improving water quality through filtration, stormwater attenuation, and woody debris and leaf litter inputs into the river.
- Native Fish Habitat: restoring shoreline habitat complexity, including alcoves and inlets for cool water refugia and off-channel habitat during periods of high river flow; and providing important resting and movement habitat for anadromous fish species.
- Water Quality: improving water temperature and chemistry above existing conditions at the site. In addition, re-establishing tail races to receive greater flows from the lagoon above will have multiple environmental benefits. The water quality of the lagoon will improve through circulation of fresh water through the area. Below, greater circulation would aerate water flowing through the tail races, thus providing a more welcoming habitat for fish and other riparian vegetation
The Willamette Falls Legacy Project provides an opportunity to enhance native habitats, protect and improve water quality for wildlife, reestablish native plant communities, and improve and sustain the natural systems that support a healthy environment. Let us know how you can help restore a healthy habitat at Willamette Falls. Sign up to become a Community Champion today!