Autonomous receiver tracks fish to improve hydropower dam operations
Toby Kock/USGS
The underwater autonomous receiver uploads tracking data from tagged salmon to the cloud in near real-time to help hydroelectric plant operators know when, where and how many fish are expected to pass through dams.
A newly developed acoustic telemetry receiver allows hydropower dam operators to continually track fish movement and health, improving environmental practices and efficient operations.
Researchers at the Pacific Northwest National Laboratory engineered an underwater autonomous receiver that uploads tracking data from tagged salmon to the cloud in near real-time, “providing timely information to dam operators and decision-makers about when, where, and how many fish are expected to pass through dams,” the lab said in an announcement.
About half of the nation’s hydroelectric dams are operated by private and public utilities, municipalities and other organizations, according to the National Hydropower Association. The dams can delay salmon migration and block their passage, making them easy prey to seals and other animals, according to the State of Salmon in Watersheds report. The facilities can also raise the water temperature and alter environmental processes, disturbing the habitat of salmon, which are protected by the federal Endangered Species Act.
The new receiver incorporates microcontrollers and integrated circuits to create real-time data communication and processing units for edge computing, according to the researchers’ paper. Co-developers Daniel Deng and Jayson Martinez said this approach enables faster transmission between transmitter and receiver by drastically reducing the volume of information being processed.
As fish tagged with transmitters navigate the dams, they produce mechanical vibrations that corresponding receivers convert into electrical signals, according to the paper. After processing and compressing that data, the receivers pass it through a wireless signal to an onshore modem that uploads the content to the cloud where dam operators can see the results visualized. There they can see historical data and conduct further analysis of the behavior and survival information of tagged animals.
While autonomous receivers are not a new development, current versions can only store data locally, forcing workers to travel to the receivers to manually download data. They also suffer from limited data rates and low energy efficiency because of the challenges of underwater operations. Additionally, the current cable receivers, while able to present real-time intelligence, can only do so in places where power is available onshore.
With the new receiver, “there’s a lot of energy saved during data transmission, which translates to more data that can be transmitted with less power, making the system more robust and efficient,” Martinez said in the announcement. “You could even potentially run the onshore acoustic modem using renewable energy, like a solar-powered battery.”
Efforts to improve fish tracking transmitters and their receivers has been a decades-long effort for underwater acoustic telemetry technology, Deng said. “Our ultimate goal is to try and provide real-time information on fish location and health, and this receiver is a big step towards that goal, providing hourly data updates to dam operators.”
As the technology also evaluates environmental factors, researchers said their platform can help others understand river habitats and fish populations in light of climate change.
Deng and Martinez plan to introduce the autonomous receiver “for large-scale deployment in the future” following successful test trials, the lab stated.