Kasnyku Falls is a waterfall located between Kasnyku Lake and Waterfall Cove on the northeast coast of Baranof Island, 7 miles (11 km) north of the community of Baranof and 20 miles (32 km) northeast of Sitka, Alaska. Kasnyku Lake is 1.7 miles (2.7 km) long and named in 1923 by the U.S. Forest Service, presumably for Kasnyku Bay. Kasnyku is a Tlingit Native name reported in 1895 by Lieutenant Commander E.K. Moore of the U.S. Navy. Kasnyku Creek flows from Kasnyku Lake and drops about 400 feet (122 m) through a narrow gorge and then plunges over the falls into Waterfall Cove. The only access to this waterfall is by aircraft or boat.
The region is rugged, mountainous, and extremely glaciated and lies within the Chilkat-Baranof Mountains section of the Pacific Border Ranges geological province. Few roads or trails exist, and most of the interior of Baranof Island is accessible only by floatplane, helicopter, or foot travel. The climate is mild and wet, characteristic of southeastern Alaska. The snow cover is gone from lower altitudes by June and from higher altitudes by August. Hemlock, spruce, and cedar grow in dense stands, and alder, devils club, and berry bushes form thick undergrowths on alluvial fans and landslide areas. Potential hydroelectric power sites have been explored on the east side of Baranof Island since 1929. One proposed site is at Kasnyku Lake that occupies a glacier gouged basin 393 feet (120 m) deep at an elevation of 595 feet (191 m).
The storage capacity of the lake is currently too small and proposed waterpower development would be best accomplished by the construction of a dam at the lake outlet above the Kasnyku Creek gorge to raise the water level 100 feet (30 m). Water would be diverted through a bored tunnel with a portal on the north shore of Kasnyku Lake near the lake outlet and extending to tidewater at Ell Cove just north of Waterfall Cove. A tunnel along this route would be approximately 2,900 feet (884 m) long and would convey water to a powerhouse installation at Ell Cove through a penstock about 1,400 feet (426 m) long. Read more here and here. Explore more of Kasnyku Falls here: