Reservoir Delta Progradation Simulator

Every dam traps the river that feeds it, and every trapped river answers by filling its own reservoir back in. This simulator models the classic Gilbert-type delta that forms where an inflowing, sediment-laden river meets the still water behind a dam: a flat topset at pool level, a steep foreset advancing toward the dam at the sediment's angle of repose, and a thin bottomset draping the deepest water. Choose a grain-size class, set the river's sediment load, and run years of deposition to watch the delta prograde down the reservoir while live readouts track how much of the original live storage capacity has been lost — the same bathymetric-survey question every reservoir operator eventually has to answer.