Mighty Copper River

The Copper River and its tributaries make up an impressive watershed of wilderness, approximately 26,500 square miles (nearly 16 million acres). The Watershed encompasses the far corners of five distinct mountain ranges.  These include the Alaska Range, the Wrangell Mountains, St. Elias Range, most of the Chugach Mountains and a small section of the Talkeetna Range. They contain sources of both volcanic and sedimentary rock from some of North America’s tallest peaks, as well the largest subpolar icefield in the world, the Bagley Icefield, making the Copper River Watershed one of the most prolific and diverse glacial deposits in the world.

On May 28, 2013, a NASA satellite captured this image of the Copper River Delta showing extraordinary sediment load in the Gulf of Alaska. The Childs and Miles glaciers, as well as the Bagley Icefield drain into the Copper River. As the glaciers slide down the mountains into the valleys, they grind on the bedrock below, creating what scientists refer to as “glacial flour.” That sediment is a good source of iron and nutrients for phytoplankton and marine plants.  These nutrients in turn support abundant wild salmon runs on the Copper River.

NASA - Copper River Delta

Mountainous glaciers blanketing the basin have been melting since the last ice age ended 12,000 years ago depositing massive amounts of glacial silt downstream, upwards of 60-100 million tons per year! The Copper River Delta coastal plain spans over 700,000 acres and stretches almost seventy-five miles along the coast.

The Copper River drains glacial silt from along its entire path. During summer months, the daily sediment load can be 750,000 cubic feet of mud and sand. Much of the river is frozen in winter from late November to April. The Copper River carries one of the largest river sediment loads known and over the past eight thousand years. The river has built up a layer of silt over 600 feet deep as it leaves the Chugach Mountains and enters the coastal plain. These depositions have formed the Copper River Delta.

Highly prized salmon way of life

All five species of wild Pacific salmon are found in the Copper River Watershed and Prince William Sound. These include Chinook/King, Sockeye/Red, Coho/Silver, Chum/Keta, and Pink/Humpy salmon. Millions of salmon migrate up and down the Copper River and Bering Glacier river systems each year on their way from or returning to their natal spawning grounds.

The delicate balance and sustainability of this system contribute to the purity and wildness of the region. The spawned out salmon provide nutrients to the animals and forest while the salmon themselves are sustained by clean water, unspoiled spawning habitat and a rich food chain in the Gulf of Alaska. The glorious cycle of life offered by wild salmon define Alaskan culture and is the backbone of our economy and coastal communities. Alaska Glacial strives to honor and show gratitude for the magnificent gifts by protecting the Copper River Watershed through philanthropy thus ensuring wild salmon’s survival for generations to come. You can read more about our GIVING BACK program by clicking here.

wild salmon