North Tenmile Lake is one of a chain of lakes along the Oregon Coast south of the Umpqua River in the United States. The chain includes Tenmile, Eel, Clear, and smaller lakes, which drain into the Pacific Ocean via Tenmile Creek. The lake is 8mi south of Reedsport and 1mi east of U.S. Route 101 near the community of Lakeside. North Tenmile Lake is connected to Tenmile Lake by a navigable 0.5mi channel.North Tenmile Lake is named after the creek, which is about 10mi south of Winchester Bay. This community, at the mouth of the Umpqua River, was the earliest pioneer village along this part of the coast.Geology and historyThe lakes in the Tenmile Creek watershed formed after rising sea levels, driven by post-glacial warming, inundated the lower reaches of the creek and its tributaries. Sand dunes that later formed along the coast altered the region's drainage patterns and led to a string of lakes at varied elevations within the Tenmile basin.In the early 20th century, North Tenmile Lake was a cold-water fishery that supported large populations of coastal cutthroat trout, salmon, and steelhead. However, the watershed was gradually altered by logging, farming, stream channeling, and the introduction of invasive fish species such as yellow perch and brown bullhead. Attempts to restore the cold-water fishery, including poisoning Eel, Tenmile and North Tenmile lakes with rotenone in 1968, all failed. Bluegill and largemouth bass are among species that have since dominated the fishery.