A total of 4,420.5 miles of railroad were constructed in South Dakota, with the last track laid in 1948. Since 1909, rail abandonment's have resulted in the loss of service on over 75% of the maximum system. The State of South Dakota, in cooperation with private railroads, was successful in restoring service on over 900 previously abandoned rail lines in the state. Currently there are 1,977 miles of operating rail lines in South Dakota.
As a result of the Milwaukee Road embargo in 1980, South Dakota was confronted with the loss of over fifty percent of its total operating rail mileage. The State analyzed each line individually and identified the essential rail lines vital to the economy of South Dakota. Some of the embargoed essential lines were purchased by other railroads and service was restored. The remaining essential lines for which a private solution could not be found were purchased by the State.