Beach renourishment, also called beach recovery or replenishment, is the act of rebuilding eroded beaches with offshore sand and gravel that is dredged from the sea floor. Renourishment projects are sometimes implemented to widen a beach for more recreational capacity, or to save structures built on an eroding sandy shoreline. The process is one that requires ongoing maintenance; the shoreline created by a renourished beach will eventually erode again. According to the National Oceanic and Atmospheric Administration (NOAA), the estimated cost of long-term restoration of a beach is between $3.3 and $17.5 million per mile.

The process itself involves dredging sand from an offshore site and pumping it onto the beach. The sand "borrow" or dredging site must also be carefully selected to minimize any negative environmental impact. Dredging can stir up silt and bottom sediment and cut off oxygen and light to marine flora and fauna.

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