Riverdale was the largest of the construction camps that sprang up in 1946 to house workers building the Garrison Dam just to the west.
It overlooks the Garrison Dam.
Hydropower turbines at Garrison Dam have an electric power generating nameplate capacity of 583.3 megawatts.
Clear water up to 180 feet deep is measured at the Garrison Dam near the lake's eastern terminus.
But in the mid-20th century, just as the population was rebounding, the federal government built the Garrison Dam.
The closure of the Garrison Dam occurred in April 1953, one year after the city's major flooding.
To help reduce the flood levels, waterflow at the Garrison Dam was completely shut off the first time in its history.
The site is now under the waters of Lake Sakakawea created by the Garrison Dam in 1953.
It was founded in 1954 as a home for those displaced by the rising backwaters of the Garrison Dam.
President Eisenhower stayed at the hotel in 1953, while visiting the recently completed Garrison Dam.