Orman Dam

Orman Dam (now known as Belle Fourche Dam) is a dam on Owl Creek in Butte County, South Dakota, USA. It was constructed in 1911 to store water for agricultural use. Its construction created Belle Fourche Reservoir. At the time it was built, Orman Dam was the largest earthen dam on Earth. In 1989, Orman Dam was designated as an official National Historic Civil Engineering Landmark. It is approximately eight miles east of Belle Fourche, South Dakota, along SD 212.

Sources: [1], [2] and [3]