Environment and development
in coastal regions and in small islands
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Coastal management sourcebooks 1


Accretion: accumulation of sand or other beach material due to the natural action of waves, currents and wind; a build-up of sand.
Armour: structural protection for the shoreline.
Artificial reef: a man-made marine habitat constructed for the purpose of improving fisheries.
Back beach: the section of beach extending landwards from the high water mark to the point where there is an abrupt change in slope or material; also referred to as the backshore.
Backfill: material used to build up and consolidate the land behind a seawall or similar structure.
Backhoe: an excavator in which the bucket faces the operator and is pulled towards him.
Bar: fully or partially submerged mound of sand, gravel or other unconsolidated material built on the sea-bottom in shallow water by waves and currents.
Barrier reef: a coral reef separated from the land by a large lagoon or, in some cases, by several kilometres of open sea.
Beach downdrift: area of beach towards which material is being moved by longshore transport.
Beachface: upper surface of the beach.
Beachface dewatering: a technique whereby water is continuously pumped away from the beachface, thereby lowering the water table under the beach.
Beach nourishment: artificial process of replenishing a beach with material from another source that lies either inland or is dredged offshore.
Beach profile: side view of a beach extending from the top of the dune line into the sea.
Beach recovery: process whereby accretion takes place at a beach, usually after a major storm or hurricane.
Beachrock: ledges of rock formed within the body of the beach consisting of sand grains cemented by calcium carbonate and formed by chemical processes. Erosion of the sand leaves the beachrock exposed.
Berm crest: ridge of sand or gravel deposited by wave action on the shore just above the normal high water mark.
Bioerosion: process by which animals, through drilling, grazing and burrowing, erode hard substances, for example rocks and coral reefs.
Bluff: high, steep bank at the water's edge; often used to refer to a bank composed primarily of soil. See also Cliff.
Breaker: a wave as it collapses on a shore.
Breaker zone: area in the sea where the waves break.
Brackish water: freshwater mixed with seawater.
Bulkhead: structure that retains or prevents the sliding of land or protects land from water damage.
Bypassing: movement of sand from the accreting updrift side of a structure, inlet or harbour entrance to the eroding downdrift side.
Cay: low island or reef of coral, sand, etc.
Cliff: high steep bank at the water's edge; often used to refer to a bank composed primarily of rock. See also Bluff.
Coastal vanes: curved structures moored to the seabed, designed to change the direction of part of the wave.
Coastal woodland: area of coastal trees and large shrubs located behind the beach, also referred to as coastal forest zone.
Conservation: the political/social/economic process by which the environment is protected and resources are used wisely.
Coral reef: complex tropical marine ecosystem dominated by soft and stony (hard) corals, anemones and sea fans. Stony corals are microscopic animals with an outer skeleton of calcium carbonate that form colonies and are responsible for reef-building.
Corrosion: wearing away of material especially by chemical action.
Cuspate foreland: an accretionary feature consisting of a triangular accumulation of sand projecting seawards from the shoreline.
Deep water: area where surface waves are not influenced by the sea-bottom.
Downdrift: direction of longshore movement of beach materials.
Dredging: excavation, digging, scraping, draglining, suction dredging to emove sand, silt, rock or other underwater sea-bottom material.
Dune: accumulations of wind-blown sand in ridges or mounds that lie landward of the beach and usually parallel to the shoreline.
Ebb-tidal current: flow of water in a given direction that takes place between high water and low water.
Ebb-tide: the falling tide, part of the tidal cycle between high water and the next low water.
Ebb-tide delta: an accretionary deposit of sand found on the seaward side of an inlet and usually formed by tidal currents.
Ecosystem: organization of the biological community and the physical environment in a specific geographical area.
Environmental impact
detailed studies which predict the effects of a development project on the environment. They also provide plans for mitigation of the adverse impacts.
Equilibrium: state of balance.
Erosion: wearing away of the land, usually by the action of natural forces.
Estuary: mouth of a river, where fresh river water mixes with the seawater.
Fetch: area of water where waves are generated by the wind.
Filter cloth: synthetic textile with openings for water to escape, but which prevents passage of soil particles.
Filter material: layer of fine gravel used in slope stabilization structures that allows water to escape and retains soil particles.
Flank protection: angled section of wall at the end of a shore protection structure, for example a seawall or revetment.
Flood-tide: rising tide, part of the tidal cycle between low water and the next high water.
Flood-tide current: flow of water in a given direction that takes place between low water and high water.
Flood-tide delta: accretionary deposit of sand found on the bay or river side of an inlet and usually formed by tidal currents.
Foreshore: zone between the high water and low water marks.
Fringing coral reef: coral reef closely associated with the land; it may be joined directly to the beach or separated from the beach by a shallow lagoon.
Frond: shoot of a seaweed resembling a leaf in more advanced plants.
Frontal system: weather system where there is a line of separation between cold and warm air masses, usually associated with strong winds.
Gabions: wire mesh rectangular containers filled with stones.
Greenhouse effect: heating of the earth's atmosphere due to an increase in gases like carbon dioxide.
Groyne: shore protection structure built perpendicular to the shore; designed to trap sediment.
Groyne field: series of groynes acting together to protect a section of beach.
High water mark: the highest reach of the water at high tide. It is sometimes marked by a line of debris, e.g. seagrass, pieces of wood.
Hurricane: intense, low-pressure weather system with maximum surface wind speeds that exceed 118 km/hr (74 mph).
Jetty: structure projecting into the sea for the purpose of mooring boats; also solid structure projecting into the sea for the purpose of protecting a navigational channel.
Land reclamation: process of creating new, dry land on the seabed.
Lee: sheltered.
Leeward: the lee side.
Leeward coast: coast sheltered from the waves.
Longshore current: a movement of water parallel to the shore, caused by waves.
Longshore transport: movement of material parallel to the shore, also referred to as longshore drift.
Low water mark: the highest reach of the water at low tide.
Mean sea level: average height of the sea surface over a 19-year period.
Monitoring: systematic recording over time.
Northeast Trade Winds: dominant wind regime in the Caribbean region; the winds blow from directions between north and southeast.
Ocean current: flow of water in a given direction in the ocean.
Offshore breakwater: structure parallel to the shore, usually positioned in the sea, that protects the shore from waves.
Offshore step: break in the offshore slope; the point where, upon walking into the water, one suddenly steps into deeper water. Usually located at about the same place as the wave breakpoint.
Offshore zone: extends from the low water mark to a water depth of about 15 m (49 ft) and is permanently covered with water.
Patch reef: small colonies of corals, sometimes less than 10 m (33 ft) in diameter.
Pile: long heavy section of timber, concrete or metal, driven into the earth or seabed as support for another structure.
Retaining wall: wall built to hold back the earth.
Retreat: movement backwards towards the land.
Revetment: shore protection structure made with stones laid on a sloping face.
Sand bar: accretionary deposit of sand formed across a river mouth or bay by wave action and joined to the shore at both ends.
Scour: removal of underwater material by waves or currents, especially at the toe of a shore protection structure.
Seagrass bed: area of the offshore sea-bottom colonized by seagrasses.
Seasonal deposition: accumulation of sand or other beach material, usually layered, resulting from winter/summer variations in coastal processes.
Seasonal erosion: loss of sand or other beach material resulting from winter/summer variations in coastal processes.
Seawall: massive structure built along the shore to prevent erosion and damage by wave action.
Sediment: particles of rock covering a size range from clay to boulders.
Setback: prescribed distance landward of a coastal feature (e.g. the line of permanent vegetation), within which all or certain types of development are prohibited.
Settling pond: man-made depression created to receive water and sand mixture directly from a dredging operation.
Shore: narrow strip of land in immediate contact with the sea.
Shoreline: intersection of a specific water height with the shore or beach, e.g. the high water shoreline is the intersection of the high water mark with the shore or beach.
Silt curtain: fine, meshed material suspended in the water to prevent silt escaping from a construction site.
Siltation: deposition of silt-sized particles.
Slurry: mixture of 70 per cent water and 30 per cent sand/silt/clay size particles; term used in dredging.
Spit: accretionary deposit of sand or stones located where a shoreline changes direction, formed by wave action and joined to the shore at one end only.
Storm surge: a rise in the sea surface on an open coast, often resulting from a hurricane.
Swamp: low-lying areas that are frequently flooded and support vegetation adapted to saturated soils e.g. mangrove swamps. See also Wetlands.
Swell: waves that have travelled out of the area in which they were generated.
Tectonic: processes that build up the earth's crust.
Tidal current: movement of water in a constant direction caused by the periodic rising and falling of the tide. As the tide rises, a flood-tidal current moves in one direction and as the tide falls, the ebb-tidal current moves in the opposite direction.
Tidal inlet: a river mouth or narrow gap between islands, within which salt water moves landwards during a rising tide.
Tide: periodic rising and falling of large bodies of water resulting from the gravitational attraction of the moon and sun acting on the rotating earth.
Toe protection: material, usually large boulders, placed at the base of a sea defence structure like a seawall to prevent wave scour.
Tombolo: accretionary deposit of sand or gravel joining a small islet or rock to a larger island or landmass. Formed by wave action.
Topography: configuration of a surface including its relief and the position of its natural and man-made features.
Tropical depression: organized low-pressure system forming in tropical latitudes with wind speeds of between 37 km/h and 60 km/h (23 mph and 37 mph).
Tropical storm: low-pressure weather system with maximum surface wind speeds between 61 km/h and 118 km/hr (38 mph and 73 mph).
Tropical wave: low-pressure system forming in tropical latitudes with wind speeds of up to 36 km/h (22 mph).
Tsunami: wave caused by an underwater earthquake or landslide; can rise to great heights and cause catastrophic damage to the coast.
Turbidity: reduced water clarity resulting from the presence of suspended material in the water.
Updrift: direction opposite to the predominant movement of longshore transport.
Vegetation edge: place where the vegetation (e.g. grasses, vines) meets the bare sand area of the back beach.
Water table: the upper surface of groundwater; below this level, the soil is saturated with water.
Wave breakpoint: the point where the waves break.
Wave direction: direction from which a wave approaches.
Wave refraction: process by which the direction of approach of a wave changes as it moves into shallow water.
Weep hole: hole through a solid revetment, bulkhead or seawall for relieving water pressure.
Wetlands: low-lying areas that are frequently flooded and which support vegetation adapted to saturated soils e.g. mangrove swamps. See also Swamps.
Wind waves: waves formed in the area in which the wind is blowing.
Windward: side facing the wind.
Windward coast: coast exposed to wave action.
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