Detroit Lake is situated over a historical road bed of the former Oregon Pacific Railroad.

Idanha had rail service until the 1950s, when the track was removed for installation of the Detroit and Big Cliff reservoirs.

[1] Part of the Willamette Valley Projects, the lake was intended primarily for flood control and power generation but has become one of the major recreation resources in western Oregon.

It is one of 32 lakes federally designated for recreation, managed by the United States Forest Service.

In 2015 and 2016 low water levels in the reservoir impacted recreation, the operation of marinas and the economy in the Santiam Canyon.