Construction on Gardiner Dam and the smaller Qu'Appelle River Dam[1] was started in 1959 and completed in 1967, creating Lake Diefenbaker upstream and diverting a considerable portion of the South Saskatchewan's flow into the Qu'Appelle River.

The Westside Irrigation Project supplies water to the west side of the South Saskatchewan River and the Eastside Irrigation Project supplies water to the east side of the South Saskatchewan River.

Phase one and two of the project will rehabilitate and expand the existing Westside Irrigation canal system.

The park was named after Gustaf Herman Danielson (former Saskatchewan Liberal Party MLA).

The dam is named for a former Premier of Saskatchewan and longtime federal cabinet minister, James G. Gardiner.