Gardiner Dam, located 100 km south of Saskatoon, is a 5 km long earth-fill structure towering 64 m above the South Saskatchewan riverbed. A dam near the "elbow" of the river (see Elbow) had first been suggested in 1858 by Henry Hind, but construction did not begin until 1958 when a cost-sharing agreement was signed by the Diefenbaker (federal) and Douglas (provincial) governments.
The dam is named after James G. Gardiner, former Saskatchewan premier. The body of water behind the dam is named Lake Diefenbaker after the man who, as prime minister, put the plan in motion (though Diefenbaker and Gardiner were arch-opponents). The dam was created to better use the water resources of the South Saskatchewan River for irrigation, recreation, urban water supply and electrical power. It was officially opened in 1967.