Copper River Sonar Site -
Miles Lake

The Copper River sonar site is located in a narrow gap in the mountains where there is a great deal of wind and fine dust. Conditions at the site are strongly influenced by the many glaciers that feed into the Copper River. The glaciers release large quantities of silt that heavily cloud the water and sometimes result in dust storms. The river’s water levels swell with increasing amounts of glacial melt water in the summer and sometimes flood when glacially-damned lakes break loose.

The Copper River site is among the most challenging sites where Alaska Department of Fish and Game operates sonar, but it also one of the longest running. ADF&G has been operating sonar to gauge the strength of Copper River sockeye runs for more than 30 years. This long history is particularly valuable at the Copper River, where extreme environmental conditions preclude fisheries biologists from using many of the tools used to gauge run strength in other salmon fisheries around the state.
Copper River
>The Site and River

The Copper River sonar site operates under extreme conditions not encountered at any other state sonar site, including icebergs from calving glaciers, extraordinarily high turbidity and very swift currents.

Copper River
>The Fish

The Copper River supports king, coho and sockeye salmon—but sockeye are by far the most abundant.

Copper River
>Sonar Tools

The Copper River site used Bendix sonar for more than 20 years, but today it uses a type of sonar technology known as DIDSON.

Copper River
>Other Tools

Although ADF&G relies heavily on sonar data to gauge the strength of returning Copper River sockeye runs, it also examines several other indicators.

Copper River

Print out a PDF copy of the Copper River sonar site Brochure

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Copper River

Copper River Photo Gallery

See glaciers, sonar transducers, ice rafts and more in the Copper River sonar site photo gallery.

Copper River

Copper River Sonar Site on Radio

Listen to an on-site report about the unique challenges of operating sonar in the Copper River during spring breakup in this radio broadcast, aired on Valdez’s KCHU 770 AM in the spring of 2011.
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