Annex Creek is a stream that flows 5 miles (8 km) southeast from Annex Lakes to Taku Inlet, about 0.4 miles (643 m) northeast of Sunny Cove and 10 air miles (16 km) east of Juneau, Alaska. The local name was first published by the U.S. Geological Survey in 1916 and adopted by the U.S. Forest Service in 1929.
In 1880, gold was discovered in Juneau at what is now known as Gold Creek. The early mining efforts were placer mines that used large water jets to wash gravel through sluices to separate the gold. Most of the placer mining along Gold Creek in the Silver Bow Basin was finished by the 1890s, and the miners’ attention was drawn to the lode, or hard-rock gold deposits. Miners soon discovered that the gold ore around Juneau was relatively low grade and to be profitable mining had to be done on a very large scale. The smaller mining operations in the Juneau area began consolidating and by 1911 there were only three large mines operating in the Juneau area: the Treadwell Mine on Douglas Island, the Alaska Juneau or AJ Mine, with a mill operating near downtown Juneau, and the Alaska Gastineau Mine operating in the community of Thane near Sheep Creek.
The Alaska Gastineau Mill was built in 1915, and a hydroelectric power project was built at Salmon Creek to power the mill. The rock crushers, conveyors, and other plant equipment were all powered with electric motors. A second hydroelectric project was built at Annex Creek when the mill’s capacity was expanded. Engineers tapped Upper Annex Lake with a tunnel 1,481 feet (451 m) long that diverted water to electric generators near sea level and the Annex Creek Hydroelectric Project came online on February 14, 1916. The Gastineau Mill closed in 1921 and remnants of the buildings are still visible on the hill above Thane. Today, the Annex Creek Hydroelectric Project is owned and operated by Alaska Electric Light and Power and still provides about 5 percent of Juneau’s electric energy demand. Read more here and here. Explore more of Annex Creek Hydroelectric here: