On June 27, 2000, the National Marine Fisheries Service (NMFS) received a biological assessment (BA) and request from the Federal Highway Administration (FHWA) for Endangered Species Act (ESA) section 7 formal consultation for a bridge replacement project over Butte Creek along Oregon Highway 211 (Woodburn to Estacada Highway) in Marion County, Oregon. NMFS reviewed the BA and requested additional information. The additional information was received from Oregon Department of Transportation (ODOT) on August 11, 2000, and a request for extending the in-water work period was received on September 25 and October 2, 2000. The FHWA is partially funding the action and is the lead Federal agency for the consultation. The ODOT has designed the project and will administer the construction contract. ODOT has also prepared the BA. This biological opinion (Opinion) is based on the information presented in the BA and during the consultation process. FHWA/ODOT is proposing to replace the bridge beginning in 2001. Construction would last approximately one year. Butte Creek is a tributary to the Pudding River within the Willamette River basin. The new two-lane bridge will be built along the same alignment as the old bridge, with a detour bridge required to carry traffic during construction. The detour bridge will have a series of pilings driven into the creeks floodplain. Approximately 445 cubic yards of riprap will be used below the two-year flood elevation to stabilize the banks under the bridge.