Lake Alvin Recreation Area in southeastern South Dakota, about thirteen miles southeast of Sioux Falls, is a state recreation area centered on a lake created in 1957 when a dam was built across the lower end of Nine Mile Creek. Located just west of the Iowa border and the Big Sioux River, it is a popular nearby destination for fishing, hiking, and swimming. The lake and recreation area were named for Alvin Dempewolf of Harrisburg, a South Dakota soldier who died overseas during World War I at age twenty-five, linking this accessible outdoor retreat to a personal local story.