As a bluff erodes, the top edge moves landward. This is a natural process that becomes a hazard when it threatens buildings or other developed property. Bluff erosion rates will vary from year to year, much like the weather. Even a steep bluff may remain unchanged for many years, or slump a large amount of sediment once every few years. Fine silt and clay eroded from bluffs may end up on mud flats or salt marshes at the base of the bluff, helping to reduce wave energy and slow the overall rate of bluff erosion. Eroded sand and gravel become part of the beach at the base of the bluff, helping to stabilize the shoreline.