WALES BEACH GUIDE

Coastal Terminology

Bight
A small bay, not deeply indented; the sea area between two headlands.
Bill
A narrow promontory
Bog
An area of soft, often waterlogged ground consisting of decaying vegetation
Bore
A large wave surging up a river estuary, caused by a fast rising tide or tidal surge
Chart Datum
Often seen on Tide Tables. A level from which water depths and tide heights are measured. Usually the lowest possible calculated tide height, so that tide tables will never show a negative height
Causeway
Causeway Causeway to St Margarets Island
A road or tidal crossing, above the sea or other wet area
Dumping Waves
Also known as Plunging waves, these occur when the face of the wave develops a concave shape, and the crest falls - often with considerable force - onto the shore. They occur mostly on beaches with a steep gradient
Dune Slack
The low-lying depressions in sand dunes, where vegetation usually flourishes
Ebb Tide
A falling tide - (the 'drop' in surfing terms)
Estuary
The tidal section of a river
Fathom
Unit of water depth - equal to 6 feet
Flood Tide
A rising tide - (the 'push' in surfing terms)
Foreshore
The area of the beach between high and low tide
Doline
A depression in the ground, often funnel-shaped, caused by the ground collapsing into a limestone cave
Groyne
A stone or timber barrier on the beach, to reduce erosion and longshore drift
Isthmus
A narrow strip of land connecting two larger areas of land
Lagoon
An area of sea water, separated from the sea by rocks or sand
Marsh
An area of wet or muddy low-lying ground frequently flooded
Neap Tides
Tides which occur around the time of a quarter moon. These have the lowest tidal range
Promontory
A point of land (usually with some height) sticking out into the sea
Purl (verb)
To flow with a soft rippling sound
Ria
Ria Solva Harbour - An example of a ria
A glaciated river valley, open to the sea
Rip current
Rip currents Rip currents at Monkstone
A body of water flowing out to sea
Roads
A sheltered area of water where boats can safely lie at anchor
Runnel
A small stream or channel, especially one which drains a tidal pool
Sand Bar
A ridge of sand projecting out into the sea usually created by river currents, and a dangerous place to be on an incoming tide
Saltmarsh
A marsh often flooded by the sea
Skerry
A small, rocky islet
Slack Water
The state of the tide around high or low tide, when there is little tidal movement
Slough
A bog or marsh, usually connecting with a river or the sea
Spilling waves
Spilling Waves
Waves in which the broken water gently tumbles down the face of the wave. These occur mostly on beaches with little gradient
Spit
A bank of sand or shingle, jutting out to sea
Spring Tides
Tides which occur around the time of a full or new moon. These have the largest tidal range
Sound
A narrow channel of water connecting two larger areas or forming an inlet; the channel between an island and the mainland
Spume
The white foam seen on waves during windy or stormy weather
Strand
The land bordering a sea or lake
Strandline
The line of sea-borne debris on a beach just above the high water mark
Tombolo
Tombolo
A spit of sand or shingle between an island and the mainland
Wave-cut Platform
A region of relatively flat rocks at the base of the cliffs, caused by sea erosion
Zawn
A steep-sided, narrow inlet in the cliffs