Accretion - the deposition of sediment, sometimes indicated by the seaward advance of a shoreline indicator such as the water line, the berm crest, or the vegetation line.
Active beach - the portion of the littoral system that is frequently (daily or at least seasonally) subject to transport by wind, waves, and currents.
Algal bloom - a sudden increase in the amount of marine algae (seaweed) often caused by high levels of phosphates, nitrates, and other nutrients in the nearshore area.
Armoring - the placement of fixed engineering structures, typically rock or concrete, on or along the shoreline to reduce coastal erosion. Armoring structures include seawalls, revetments, bulkheads, and rip rap (loose boulders).
Backshore - the generally dry portion of the beach between the berm crest and the vegetation line that is submerged only during very high sea levels and eroded only during moderate to strong wave events.
Beach - an accumulation of loose sediment (usually sand or gravel) along the coast.
Beach loss - a volumetric loss of sand from the active beach.
Beach management district - a special designation for a group of neighboring coastal properties that is established to facilitate cost sharing and streamline the permitting requirements for beach restoration projects.
Beach narrowing - a decrease in the useable beach width caused by erosion.
Beach nourishment - the technique of placing sand fill along the shoreline to widen the beach.
Beach profile - a cross-sectional plot of a shore-normal topographic and geomorphic beach survey, usually in comparison to other survey dates to illustrate seasonal and longer-term changes in beach volume.
Berm - a geomorphological feature usually located at mid-beach and characterized by a sharp break in slope, separating the flatter backshore from the seaward-sloping foreshore.
Building setback - the county-required seaward limit of major construction for a coastal property. Building setbacks on Maui vary from 25 feet to 150 feet landward of the certified shoreline.
Coastal dunes - dunes within the coastal upland, immediately landward of the active beach.
Coastal erosion - the wearing away of coastal lands, usually by wave attack, tidal or littoral currents, or wind. Coastal erosion is synonymous with shoreline (vegetation line) retreat.
Coastal plain - the low-lying, gently-sloping area landward of the beach often containing fossil sands deposited during previously higher sea levels.
Coastal upland - the low-lying area landward of the beach often containing unconsolidated sediments. The coastal upland is bounded by the hinterland (the higher-elevation areas dominated by bedrock and steeper slopes).
Day-use mooring - a buoy or other device to which boats can be secured without anchoring.
Deflation - a lowering of the beach profile.
Downdrift - in the direction of net longshore sediment transport.
Dune - a landform characterized by an accumulation of wind-blown sand, often vegetated.
Dune restoration - the technique of rebuilding an eroded or degraded dune through one or more various methods (sand fill, drift fencing, revegetation, etc.).
Dune walkover - light construction that provides pedestrian access without trampling dune vegetation.
Dynamic equilibrium - a system in flux, but with influxes equal to outfluxes.
Erosion - the loss of sediment, sometimes indicated by the landward retreat of a shoreline indicator such as the water line, the berm crest, or the vegetation line.
Erosion hotspots - areas where coastal erosion has threatened shoreline development or infrastructure. Typically, the shoreline has been armored and the beach has narrowed considerably or been lost.
Erosion watchspots - areas where the coastal environment will soon be threatened if shoreline erosion trends continue.
Foreshore - the seaward sloping portion of the beach within the normal range of tides.
Hardening - see Armoring.
Improvement districts - a component of a beach management district established to help facilitate neighborhood-scale improvement projects (e.g., beach nourishment).
Land banking - the purchase of shoreline properties by a government, presumably to reduce development pressure or to preserve the parcel as a park or as open space.
Littoral budget - the sediment budget of the beach consisting of sources and sinks.
Littoral system - the geographical system subject to frequent or infrequent beach processes. The littoral system is the area from the landward edge of the coastal upland to the seaward edge of the near-shore zone.
Longshore transport - sediment transport down the beach (parallel to the shoreline) caused by longshore currents and/or waves approaching obliquely to the shoreline.
Lost beaches - a subset of erosion hotspots. Lost beaches lack a recreational beach, and lateral shoreline access is very difficult if not impossible.
Monitoring - periodic collection of data to study changes in an environment over time.
Nutrient loading - the input of fertilizing chemicals to the nearshore marine environment, usually via non-point source runoff and sewage effluent. Nutrient loading often leads to algal blooms.
Offshore - the portion of the littoral system that is always submerged.
Overwash - transport of sediment landward of the active beach by coastal flooding during a tsunami, hurricane, or other event with extreme waves.
Revetment - a sloping type of shoreline armoring often constructed from large, interlocking boulders. Revetments tend to have a rougher (less reflective) surface than seawalls.
Scarp - a steep slope, usually along the foreshore and/or at the vegetation line, formed by wave attack.
Scarping - the erosion of a dune or berm by wave-attack during a storm or a large swell.
Sea bags - large sand-filled geotextile tubes used in coastal protection projects.
Seawall - a vertical or near-vertical type of shoreline armoring characterized by a smooth surface.
Shoreline setback - see Building setback.
Siltation - the input of non-calcareous fine-grained sediments to the nearshore marine environment, or the settling out of fine-grained sediments on the seafloor.
Storm surge - a temporary rise in sea level associated with a storm's low barometric pressure and onshore winds.
Urban runoff - the input of hydrocarbons, heavy metals, pesticides, and other chemicals to the nearshore marine environment from densely populated areas.
Zooxanthellae - unicellular, symbiotic algae living within coral polyps that produce food for their hosts by photosynthesis and help efficiently recycle low-levels of nutrients.
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