Cascade Falls descends to Cascade Bay, an estuary extending 1.5 miles (2.4 km) northwest from Eaglek Bay in northern Prince William Sound, about 52 miles (84 km) west-southwest of Valdez and 32 miles (51.5 km) east-northeast of Whittier, Alaska. The local name refers to a waterfall at the bay’s head, first reported in 1952 by the U.S. Geological Survey. This is the largest waterfall in Prince William Sound, descending 170 feet (52 m) to tidewater from three interconnected lakes all within the Chugach National Forest. The first lake sits at 170 feet (52 m) and receives meltwater from Eaglek Glacier. The second lake, at 270 feet (82 m), is fed by two deglaciated cirque lakes, or tarns. The highest lake is at 470 feet (143 m), nourished by an unnamed glacier on the west flank of Peak 4015. Eaglek Glacier, about 1.5 miles (2.4 km) across, caps the ridge above Cascade Bay on the south flank of Peak 4015. Like all cirque glaciers in northern Prince William Sound, Eaglek Glacier has been steadily retreating. Warmer winter temperatures have raised the snowline, reducing the snow accumulation area. Lighter-colored rock now marks areas of recent retreat. The mountains along the shores of Prince William Sound are part of one of the world’s largest accretionary complexes. This complex has been known by various names as geological understanding of Alaska’s southern margin has evolved. It is now generally referred to as the Southern Margin Composite terrane. At Cascade Bay, the rocks belong to the Valdez Group, formed during the Late Cretaceous period. They consist primarily of complexly deformed, partially metamorphosed sedimentary rock such as graywacke, siltstone, and shale. These are generally considered deposits of turbidity currents in a deep oceanic trench.

The northern coast of Prince William Sound was historically the territory of the Kniklik tribe of the Chugach Sugpiaq people. In the past, there were eight tribes of the Chugach: the Nuchek, Shallow Water, Sheep Bay, Gravina Bay, Tatitlek, Kiniklik, Chenega, and Montague Island peoples. These tribes shared the same culture and language and entertained each other at feasts, yet they were politically independent. Each group had its own chief or leader and a principal village. The tribes occasionally raided one another but might also unite against common enemies such as the Tlingit, Eyak, Dena’ina, or Koniag. The Kiniklik tribe inhabited an area with the most valley glaciers reaching tidewater, including the Columbia Glacier. The main village’s historical location is unknown, as the village of Kiniklik appears relatively modern and was abandoned by 1930. There were at least three historical summer settlements or fish camps in Eaglek Bay. The Chugach people once buried their dead in sea caves. In the early 20th century, mummies were found wrapped in sea otter skins with paddles beside them. Upon removal, the mummies and fur robes disintegrated. In another cave, six mummified men were discovered dressed in armor and groundhog skins, some wearing masks depicting human faces. These remains were taken to Valdez and subsequently disappeared. The Chugach Sugpiaq were likely the first Indigenous people to encounter Russian explorer Vitus Bering in 1741, followed by explorers from Spain, France, and the United Kingdom, as well as American maritime fur traders. Their population was drastically reduced by disease, subjugation by Russians, and internecine warfare. Today, remaining Chugach Sugpiaq villages include Chenega Bay, Eyak, Nanwalek, Port Graham, and Tatitlek.

The Chugach National Forest, established in 1907 and expanded in 1908 with the addition of the Afognak Forest and Fish Culture, encompasses parts of Prince William Sound, the Kenai Peninsula, and the Copper River Delta. Unusually for a national forest, less than 2% is deemed suitable for commercial logging. Instead, the forest boosts local economies through tourism, recreation, mining, and commercial fishing. In response to historically low salmon numbers, Alaska’s modern hatchery program began in the early 1970s. Hatcheries enhance salmon production by improving survival rates during early life stages, when most mortality occurs. They produce large numbers of fry or smolts, which are released into marine waters to face the same conditions as wild salmon. Unlike fish farms, hatcheries do not rear fish to adulthood; they incubate fertilized eggs and release the offspring. Under hatchery conditions, developing embryos are protected from environmental threats like low stream flows, freezing, gravel scouring from floods, and predation. There are five hatcheries in Prince William Sound: Cannery Creek in Unakwik Inlet, Lake Bay on Esther Island, Port San Juan on Evans Island, Solomon Gulch in Port Valdez, and Main Bay. In 1994, an expansion of the Main Bay Hatchery was proposed, and new sites for sockeye salmon enhancement were considered. The Prince William Sound Aquaculture Corporation obtained a state permit for Cascade Bay in Eaglek Bay, located in the Chugach National Forest on U.S. Forest Service land. However, field tests revealed that the water temperature in Cascade Lakes is too cold for sockeye salmon incubation and rearing due to its glacial water source, leading to the abandonment of the site’s development. Read more here and here. Explore more of Cascade Bay and Eaglek Bay here: