The view overhead Lewis and Clark Lake at Springfield, South Dakota, tells the story of accumulating sediment. These photos near Springfield were taken Sunday, Oct. 11, 2015. Lewis and Clark Lake is expected to be half full of sediment by the year 2045. In just 30 years the lake will change drastically; however, there are ideas on how to address sedimentation. Some have cited a three-pronged strategy: reduce, remove and manage. Several other methods also have been discussed.