Shorezone Terminology

 

ACCRETION: Beach build up by sand movement. (1)

ANCHOR GROIN: Designed to stabilize a length of shoreline by capturing a proportion of any material drifting along the shore, or by retaining a quality of introduced fill.  Once this material is caught, the design allows for bypassing, either over or around the groyne, so as to maintain drift (Carter, 1988).

BACKSHORE: The zone of the shore or beach lying between the foreshore and the shoreland and acted upon by waves only during severe storms, especially when combined with exceptionally high water (Veatch and Humphrys, 1964).

BANK:  A landward-facing steep bluff or sharp slope of unconsolidated material landward of the shoreline; the bluff.

BEACH:  A shore of unconsolidated material, usually sand and/or pebbles (U.S. Army Corps of Engineers, 1973).

BERM: A substantial high-water sand body forming a beach ridge (linear mound-shaped ridges roughly paralleling the coast).

BLUFF: A lakeward-facing steep bank or sharp slope of unconsolidated material landward of the shoreline; the bank.

BLUFF BASE:  The point or line of abrupt change in slope at the bottom of the bluff; the bluff toe. 

BLUFF CREST:  The point of line of abrupt change in slope at the top of the bluff; the bluff line.

BLUFF FACE: The lakeward facing inclined surface of the bluff; the bluff slope.

BLUFF LINE:  The point or lone of abrupt change in slope at the top of the bluff; the bluff crest.

BLUFF TOE:  The point or line of abrupt change in slope at the bottom of the bluff; the bluff base.

BLUFF SLOPE: The lakeward-facing inclined surface of the bluff; the bluff face.

BREAKER ZONE:  The area of water bounded by the beach and plunge line; the plunge line is the line along which the highest waves break (Russell and MacMillan, 1970).

BREAKWATER: A structure protecting a shore area, harbor, anchorage, or basin from waves; it is usually parallel to the shore and built in the nearshore zone (U.S. Army Corps of Engineers, 1973).

DEEP WATER WAVES: C = (gL/2)½  when h/L > ½, L = wave length. 

EDGE WAVES: Secondary wave motions that develop at right angles to the shoreline and differ from reflected waves in that they are resonant and, in theory at least, of unlimited height.

FETCH: The distance over which the wind is in contact with the water. (1)

FOREDUNE: The front sand dune immediately behind the backshore (U.S. Army Corps of Engineers, 1973).

FORESHORE: The part of the shore, or beach, normally covered by the uprush and backrush of waves (Veatch and Humphrys, 1965).

GABION: Wire basket filled with rock placed to form a groin or revetment. (1)

GROIN (GROYNE): A shore protection structure built usually perpendicular to the shoreline in order to trap littoral drift or retard erosion of the shore (U.S. Army Corps of Engineers, 1973).

HAMMER HEAD GROYNE: A typical groyne but has a breakwater placed parallel to the shore at the head of the groyne.

INSHORE (ZONE): The zone of variable width extending from the shoreline through the breakwater (Gray, McAfee, and Wolf, 1972); essentially the same as the littoral zone.

JETTED: Sand excavation using water under pressure. (1)

JETTY:  A structure extending into a body of water designed to prevent shoaling of a channel by littoral material and to direct ant confine stream flow (U.S. Army Corps of Engineers, 1973).

LAKESHORE: A general term used to denote the margin of the lake or a particular side of the lake.  It does not refer to a specific area within the shorezone; the lakeside.

LAKESIDE: A general term used to denote the martin of the lake or a particular side of the lake.  It does not refer to a specific area within the shorezone; the lakeshore.

LITTORAL CURRENT: Any current in the littoral zone (inshore zone) caused primarily by wave action, e.g., a longshore or rip current (U.S. Army Corps of Engineers, 1973).

LITTORAL DRIFT: The sedimentary material moved in the littoral zone under the influence of waves and currents (U.S. Army Corps of Engineers, 1973).

LITTORAL ZONE: An indefinite zone extending lakeward from the shoreline to just beyond the breaker zone (U.S. Army Corps of Engineers, 1973); essentially the inshore zone.

LONGARD TUBE: Nylon tube filled with sand used as a groin or revetment. (1)

LONGSHORE SAND BAR:  A low, elongate submerged and ridge(s), built chiefly by wave action, occurring at some distance from, and extending generally parallel with, the shoreline, and typically separated from the beach by an intervening trough(s) (Gray, McAfee, and Wolf, 1972).

LONGSHORE CURRENT:  The littoral current in the breaker zone moving essentially parallel to the shore, usually generated by waves breaking at an angle to the shoreline (U.S. Army Corps of Engineers, 1973).

LONGSHORE DRIFT: The material transported by a longshore current (American Geological Institute, 1974).

MASTIC: Mixture of sand, mineral filler, and asphalt commonly mixed with rock to form a groin or revetment. (1)

MOVEABLE STRUCTURE: Means a permanent structure which is determined to be moveable based on a review of the design and size of the structure, a review of the capability of the proposed structure to withstand normal moving stresses, and a site review to determine whether the structure is accessible to moving equipment.(2)

NAMI RINGS: Round concrete barrels put on the beach front and filled with sand.

NEARSHORE (ZONE): The indefinite zone extending from the shoreline well beyond the breaker zone defining the area of nearshore currents, and including the inshore zone and part of the offshore zone (Gray, McAfee, and Wolf, 1974).

NEARSHORE CURRENT SYSTEM:  The current system caused primarily by wave action in and near the breaker zone; four main components comprise the system: The shoreward mass transport of water, longshore currents, lakeward return flow, including rip currents and the longshore movement of the expanding heads of rip currents (U.S. Army Corps of Engineers, 1973).

NOURISHMENT: Addition of sand to a beach to act as a shore protection measure.(1)

OFFSHORE BREAKWATER: Walls placed parallel to shore in lake so littoral currents can move along with shore behind them, and wave energy can be dissipated.(1)

OFFSHORE (ZONE): The shallow bottom lakeward of the breaking waves (Bloom, 1978); this zone is of variable width and is lakeward of the inshore zone (Gary, McAfee, and Wolf, 1972; U.S. Army Corps of Engineers, 1973).

PERMANENT STRUCTURE: Means a residential building, commercial building, industrial building, institution building, mobile home, accessory and related buildings, septic system, tile field or other waste handling facility erected, installed, or moved on a parcel of property.  This definition does not include recreational vehicles or travel trailers; nor does it include appurtenant structures that are less than     15 feet by 15 feet by 10 feet high which are used for picnicking, storage of recreational or lawn equipment, and are constructed in a manner which facilities easy removal.  The appurtenant structure shall not have a permanent foundation and shall not be used as a residential facility. (2)

REVETMENT: A facing of stone, concrete slabs, etc. built to protect a scarp, embankment, or shore structure against erosion by wave action or currents (U.S. Army Corps of Engineers, 1973).  Protective blanket built parallel to the shore.

RIP CURRENT: A strong current flowing lakeward from the shore (U.S. Army Corps of Engineers, 1973).

RIPRAP: A layer, facing, or protective mound of stones randomly placed to prevent erosion, scour, or sloughing of a structure or embankment; also the stone so used (U.S. Army Corps of Engineers, 1973).

SANDBAGS: Nylon bags filled with sand (used to build a groin or revetment). (1)

SEAWALL: A structure separating land and water areas, primarily designed to prevent erosion and other damage due to wave action (U.S. Army Corps of Engineers, 1973). 

SET-UP: Wind applies stress to the water surface, the surface responds by piling up on the leeward (downside) side of the lake (denivellation).  Surges are events where there is a piling up of water in shallow water, created by massive pressure differences created by violent storms.

SHALLOW WATER WAVES: C = (gL)½  when h/L < ½, h = depth.

SHORE: The zone lakeward of the shoreland over which the ground is alternatively exposed and covered by waves; the shore's upper boundary is the lakeward limit of effective wave action at the base of the bluffs and its lakeward limit is the water line.  It may be subdivided into a foreshore and a backshore (Gray, McAfee, and Wolf, 1972).

SHORELAND: The zone of land of indefinite width that extends from the base of the bluffs inland to the first major change in terrain feature; the bluff is the lakeward margin of the shoreland (Gary, McAfee, and Wolf, 1972).  In essence, it is the lake margin equivalent of "coast," which is an ocean or sea margin term (Veatch and Humphyrs, 1964).

SHORELINE: The line separating water and the land; the water line.

SHOREZONE: The combined nearshore zone, shore, and shoreland.

STEEL PILING: Large steel sheets jetted into a beach or lake bottom used as a groin or seawall.(1)

TERMINAL GROYNE: Effectively stops longshore transport of sediment (Carter, 1988).

TETRAPODS: Large irregular shaped concrete blocks (jacks) piled on the beach to absorb the wave energy.

TIMBER CRIBS: Timber boxes filled with rock used as groins.

TIMBER PILING: Timber placed in beach or lake bottom built as a groin or seawall. (1)

VERTICAL SEAWALL: Constructed of resistant interlocking blocks, can have wave breaking piles located seaward of the wall.

WATER LINE: The line separation water and the land; the shoreline.

ZIG-ZAG PANELS: Concrete panels used as offshore breakwaters or seawalls. (1)

 

REFERENCES

1) Michigan's Demonstration Erosion Control Program; Evaluation report, November 1974.

2) Great Lakes Shoreland Erosion; Prepared by Division of Land Resource Programs Department of Natural Resources, 1982.

Copyright © 2011 W.Richard Laton, Ph.D.


Associate Professor of Hydrogeology


California State University, Fullerton


Department of Geological Sciences


(657) 278-7514