Gardiner Dam, was at the time of construction, the largest earth-filled dam in the world and continues today, 48 years after completion, to regulate the flow of water into the South Saskatchewan River.
Today, drinking water from Lake Diefenbaker is used either directly or indirectly by three of Saskatchewan’s major centers: Saskatoon, Regina and Moose Jaw and is well utilized by rural communities and farms, bringing the total consumption of drinking water to over 45% of the province’s population!
To prevent drought, Lake Diefenbaker’s water levels are regulated to ensure the communities, irrigators, industry and other water users will have water available during very dry conditions in the area.
One of Lake Diefenbaker’s greatest assets is its ability to supply water for irrigation.
Evaporation is the largest consumptive use of Lake Diefenbaker water. On average, the lake gives up 345,000 cubic decameters of water to evaporation each year. A total comparable to losing water from 90,000 Olympic-sized swimming pools!
From 1959-1967, construction of both the Gardiner Dam and the Qu’Appelle River Dams cost about $120 million, to replace them today would cost approximately $1 billion.
About 94% of the water released from Lake Diefenbaker passes through the penstocks of the Coteau Creek Power Station to produce electricity for the province!
When the South Saskatchewan River Project was completed in 1967, 100 million cubic meters of earth had been excavated to form the reservoir!
The Gardiner Dam Spillway is more than a kilometer long and required 280,000 cubic meters of reinforced concrete!