However , sedimentation has been much lower than predicted , and it is now estimated that the useful lifespan of the dam will be 85 years , to about 2060 .
The useful life of the dam and reservoir was estimated to be approximately 50 years .
Sedimentation has been much lower than predicted , and it is now estimated that the useful lifespan of the dam will be 85 years , to about 2060 .
The useful life of the dam and reservoir was estimated to be approximately 50 years .