From the record
“The Ouachita River Lock and Dam No. 8 are a historic lock and dam on the Ouachita River in Calhoun County, Arkansas. The area is managed by the county and the Arkansas Fish and Game Commission as a public recreation area.”
Wikipedia article Ouachita River Lock and Dam No. 8, CC BY-SA 4.0.
One of 9 National Register listings published here for Calhoun County · listed in 1983 · category: Structure.
Sources: the Wikipedia article · the National Register database, National Park Service