September 10, 2014Read More…
1120 SW 5th Avenue, Room 1000, Portland, OR 97204
The confluence of Errol and Johnson creeks was straightened and rock-lined decades ago. There were also two fish passage barriers in the creek, and the area was infested with invasive vegetation. Environmental Services purchased three residential properties in the area through its Willing Seller Land Acquisition Program and planned a project to restore the area and improve fish passage.
The Errol Creek Confluence Project, completed in October 2009, included vacating SE 44th Avenue, removing fish barriers and day-lighting the section of Errol Creek that once flowed underneath SE 44th to improve fish passage between Johnson Creek and Errol Creek. The project moved the confluence of Johnson Creek and Errol Creek 50 feet south and created a new, longer, more sinuous channel. The first 50 feet of the old channel remains in place as a backwater channel to provide high flow refuge for fish and flood water storage from Johnson Creek.
The project created about 300 feet of new tributary habitat to increase in-stream complexity and enhanced 1.4-acres of surrounding riparian and floodplain habitat by creating wetland benches and planting native vegetation. Environmental Services installed 77 pieces of large wood and root wads to provide floodplain structure and stabilize Errol Creek's banks and its confluence with Johnson Creek. The project also included planting 920 tree seedlings, 1,190 shrub seedlings, 650 shrub cuttings, and 41 pounds of native grass seed.
The confluence of Errol Creek and Johnson Creek is a unique natural resource. Wetlands and an extensive upstream spring system feed cool water into Errol Creek year-round. In Johnson Creek, warm water in the summer and high velocity stream flows in the winter make it difficult for juvenile salmon to survive. But Errol Creek's abundant, cool spring water near Johnson Creek is ideal summer and winter refuge and rearing habitat for steelhead, Chinook and coho salmon, and cutthroat trout.
An Oregon Department of Fish and Wildlife survey in 2000 recommended removing culverts along Errol Creek and creating off-channel refuge to enhance salmon rearing habitat. The 2001 Johnson Creek Restoration Plan identified Errol Creek as having good fish habitat potential.
This project is one of four Supplemental Environmental Projects required by a Mutual Agreement and Order (MAO) the city signed with the Oregon Department of Environmental Quality. This MAO addresses city sewage spills from 2001 to 2007.