Creeping water primrose, also called Ludwigia, is an invasive aquatic plant that had started choking out the Willamette Slough in recent years. The species impacts water quality, wildlife habitat, and recreational opportunities. Recreationists who enjoyed paddling and fishing in the slough found it increasingly difficult to do so due to the dense growth of this fast-spreading aquatic weed. The dense mats of Ludwigia were impeding water movement, blocking growth of native aquatic and riparian plants, reducing dissolved oxygen, which is essential for survival of aquatic organisms. Ludwigia also reduced the amount of habitat available for fish and wildlife that previously lived, reproduced, or stopped over in the slough, including native freshwater turtles, amphibians, waterbirds, fish, and other wildlife.

In 2019, Willamette Riverkeeper was awarded three years of funding (extended for a fourth year) to restore the Willamette Slough in partnership with the City of Salem. The project, which officially started in 2020, consisted of treatment of the Ludwigia throughout the slough using an aquatic-approved herbicide applied by a state-licensed contractor. The goal is to control the spread of this highly invasive plant within the Willamette Slough and reduce its spread to downstream locations in the Willamette River. In the fourth and final year of the grant funded project, native riparian vegetation was planted along the edges of the slough and native aquatic plants reintroduced in select locations.

This restoration effort complements the City of Salem's other restoration efforts occurring at Minto Island Conservation Area, as well as the efforts of Willamette Riverkeeper and the Willamette Aquatic Invasive Network within the greater Willamette River Watershed.

The project completed the fourth of four years of treatment for aquatic weeds. 2023/24 treatments included the planting of more than 12,000 new willows and other plants along the banks of the slough.

Status: In progress. Ongoing efforts are occurring via paddle and pull events planned for the summer of 2024 with Willamette Riverkeeper and Elderberry Wisdom Farms.

Funding for this project is provided by: Meyer Memorial Trust and Bonneville Power Administration

We are grateful for the support of the following organizations who helped to make this project possible: City of Keizer, Glenn Gibson Watershed Council, Marion Soil and Water Conservation District, North Santiam Watershed Council, Oregon Department of Fish and Wildlife, Oregon State Parks, Salem Audubon Society, Salem Environmental Education, and Willamette Riverkeeper.

The 307-acre Minto Island Conservation Area (MICA) is located at the northernmost end of Minto-Brown Island Park, nestled between the Willamette River and Willamette Slough. The City of Salem purchased the conservation area in 2013 using funding provided by Bonneville Power Administration and Oregon Department of Fish and Wildlife. This funding was provided for the primary purpose of protecting, restoring, and maintaining the diverse mix of natural habitats found in the MICA.

Prior to its purchase by the City, this piece of land was privately owned, and about 100 acres the property was used for industrial purposes (storage and processing of paper mill waste). Although the industrial site was officially closed in 1985 and subsequently remediated, many parts of the conservation area remain ecologically altered and are in need of restoration to restore floodplain function, reestablish native plant communities, and provide habitat for the many wildlife species that historically inhabited this area.

To this effort, multiple phases of floodplain restoration are planned.

This first phase of floodplain restoration was implemented between 2016 to 2020 to address the loss of floodplain forest and scrub habitat due to the park’s historical use for industry and farming. The primary focus of this project was the removal and control of invasive weeds and the planting and establishment of native plants on 103.5 acres of floodplain in the eastern portion of MICA, adjacent to the Willamette Slough. Restoration of this habitat type along the Willamette River will expand the floodplain forest, increase Salem’s tree canopy, and provide important nesting and foraging opportunities for several songbirds listed as threatened or species of concern.

Status: Complete.

Funding for this project was provided by: Oregon Watershed Enhancement Board (OWEB) and Meyer Memorial Trust

This phase of floodplain restoration in MICA focused on enhancing, restoring, and expanding the riparian floodplain forest and seasonally inundated wetland habitats within 48 acres on the west side of the conservation area adjacent to the Willamette River. This project focused on treating invasive weeds and planting thousands of native plants. The restoration work began in 2019 and was completed in 2024. The site still requires additional work to reach the desired conditions.

Status:In progress. The project is in the final year of the five-year grant to complete restoration activities. In Spring 2024 the City applied for an Oregon Watershed Enhancement Board Restoration Grant to continue work in the Phase 3 area for five additional years.

Funding for this project was provided by: Bonneville Power Administration ---and Meyer Memorial Trust

Up until recently, portions of Pringle Creek right above its confluence with the Willamette River were obstructed and hidden under layers of concrete from the former Boise Cascade Paper Mill. This project removed the concrete remnants and returned the creek channel to a more natural condition. Site improvements included a new channel that includes a more natural fishway that replaced an old fish ladder, boulders and large natural wood structures that provide stream roughness and habitat refuge, and native Oregon trees and shrubs planted on both sides of the creek to shade the creek and help keep it cool. All these design elements provide better habitat for fish and other aquatic animals that live in the creek.

Status: Monitoring and Maintenance. We are still working to establish native vegetation on the banks and riparian area and prevent invasive species from taking over before native plant cover is established.

Funding: South Waterfront Urban Renewal Area and City of Salem stormwater utility funds.