A Feeder bluff is a coastal

cliff In geography and geology, a cliff is an area of rock which has a general angle defined by the vertical, or nearly vertical. Cliffs are formed by the processes of weathering and erosion, with the effect of gravity. Cliffs are common on co ...

or headland that, through erosion and weathering, provides sediment to down-current beaches as a result of

littoral drift Longshore drift from longshore current is a geological process that consists of the transportation of sediments (clay, silt, pebbles, sand, shingle) along a coast parallel to the shoreline, which is dependent on the angle incoming wave direction ...

. First discussed at

Western Washington University Western Washington University (WWU or Western) is a public university in Bellingham, Washington. The northernmost university in the contiguous United States, WWU was founded in 1893 as the state-funded New Whatcom Normal School, succeeding a pri ...

, the term ''feeder bluff'' is primarily used to describe eroding bluffs in the

Puget Sound Puget Sound ( ) is a sound of the Pacific Northwest, an inlet of the Pacific Ocean, and part of the Salish Sea. It is located along the northwestern coast of the U.S. state of Washington. It is a complex estuarine system of interconnected ma ...

region of the United States. A bluff will be more susceptible to

weathering Weathering is the deterioration of rocks, soils and minerals as well as wood and artificial materials through contact with water, atmospheric gases, and biological organisms. Weathering occurs ''in situ'' (on site, with little or no movement) ...

and

erosion Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is dis ...

if it contains unconsolidated

sediment Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sa ...

(such as silt or sand), softer (or more erodible) rock,

fissures A fissure is a long, narrow crack opening along the surface of Earth. The term is derived from the Latin word , which means 'cleft' or 'crack'. Fissures emerge in Earth's crust, on ice sheets and glaciers, and on volcanoes. Ground fissure ...

fractures Fracture is the separation of an object or material into two or more pieces under the action of stress. The fracture of a solid usually occurs due to the development of certain displacement discontinuity surfaces within the solid. If a displa ...

. Wave activity and power will also contribute to the rate of erosion. A bluff will retreat away from the ocean as the erosion processes continue. Although coastal processes can be complex, feeder bluffs are recognized as an important source of sediment for building and maintaining nearby beaches. Practices of armoring beaches and bluffs against erosion have caused beaches and habitats to erode away due to the decreased availability of sand and gravel. One of the goals of the Puget Sound Nearshore Ecosystem Restoration Project is to reverse this process by identifying and removing bulkheads from beaches and bluffs. In 2013 the

Washington State Department of Ecology The Washington State Department of Ecology (sometimes referred to simply as "Ecology") is the state of Washington's environmental regulatory agency. Created in February 1970, it was the first environmental regulation agency in the U.S. predating t ...

completed mapping and categorization of feeder bluffs in the Puget Sound, finding they make up about 426 Miles (17%) of the shoreline. The data has been made available at th
Washington State Coast Atlas

References

Further reading