Passive acoustic data collected using stationary hydrophones on rivers in the Willamette River Basin, Oregon

Underwater passive acoustic monitoring was conducted at multiple sites on rivers in the Willamette River Basin, Oregon. Hydrophones were used to record the sound associated with coarse river-bed sediment (bedload) movement. Bedload supply and transport are key factors determining channel morphology in gravel-bed rivers and can affect reach-scale conditions such as aggradation and incision as well as the formation of smaller-scale channel landforms such as gravel bars and riffles. Bedload transport also has implications for aquatic species that depend upon river-bed sediment, such as macroinvertebrates that dwell in the riverbed and Endangered Species Act (ESA)-listed salmonids that require suitable size substrates for spawning. Therefore, relating bedload transport to streamflow is important for understanding hydrogeomorphic and habitat responses to streamflows, and can be used to inform ecologically sustainable river management decisions (such as environmental flow and river restoration programs), particularly in reaches downstream of dams with altered streamflow and sediment regimes.

This data release includes a subset of audio files, in Free Lossless Audio Codec (FLAC) format, collected at three sites on the North Santiam River (Greens Bridge, Mehama, and above Stout Creek) and two sites on the McKenzie River (Walterville and Berggren Watershed Conservation Area). Audio files were recorded for 1 minute every 15 or 30 minutes from 2021 to 2024, generally between November and May of each year. These raw audio files are provided as-is and may contain channel-specific recording errors. Subject to additional quality assurance and control and analysis, these audio files may be useful as a bedload surrogate.

Two sample hydrophone audio files recorded at the Greens Bridge site collocated with USGS streamgage 14184100 - North Santiam River at Greens Bridge, near Jefferson, Oregon are provided to illustrate the range of sound at different streamflows. File names denote site name and timestamp (in Pacific Standard Time) in Month, Day, Year-Hours, Minutes, Seconds format (SiteName_MMDDYY-HHMMSS.flac). Streamflows were at 3,460 cubic feet per second (cfs) during the December 12, 2022 recording and 11,400 cfs during the January 8, 2023 recording. Also included is a photograph depicting two hydrophones secured to rebar and installed at the Berggren Watershed Conservation Area site on the McKenzie River.