 Lake Erie Shore Erosion Management Plan
Appendix: Glossary
Anoxic: Describes an area lacking oxygen, typically within water. An anoxic zone can have significant negative impacts on fish and wildlife.
(See Lake Erie Oxygen Depletion maps in the Ohio Coastal Atlas)
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Bank: A landform similar to a bluff but lower in height, at most reaching only 20 feet above lake level, and usually containing a less complex set of soils than a bluff.
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Bar: An offshore ridge of sediment (usually sand) formed by waves and currents.
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Beach Nourishment: An erosion control measure that involves the placement of sand within the shore zone to build up the beach thickness and width.
See also shore structure webpage
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Benthic: Organisms living at the bottom of a body of water or within the sediment of the lakebed; also referring the bottom zone of the lake, including organisms and sediment. In contrast organisms living within the open waters of a body of water are referred to as pelagic.
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Bluff: The natural upland area adjacent to the lake that typically rises 20 feet or more above the elevation of the lake. Bluff is often used synonymously with “bank,” although banks are lower in height. A bluff may consist of bedrock, soil, or a combination of both.
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  Breakwater: A large pre-cast concrete block or armor stone structure attached to and built at an angle from the shore that reduces the energy of approaching waves, creating a calm environment landward of the structure.
See also shore structure webpage
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Bulkhead: A retaining wall used to separate water from land. Bulkheads are typically used for piers and boat moorings in areas of low energy. Bulkheads are typically constructed with steel sheet-pile in harbors, marinas and along rivers.
See also shore strucure webpage
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Confined Disposal Facility (CDF): A structure designed and constructed to safely contain contaminated sediments dredged from navigation channels. Sediments are often dredged as a mix of sand, mud and water requiring many CDF structures to be semi-permeable. The structures are intended to retain contaminated sediments while allowing excess water to return to the Lake. The structures are typically constructed with steel sheet pile and armor stone with layers of smaller stone or gravel at the core.
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Cohesive: Sediment containing a significant portion of clays which allows the sediments to bind together, particularly when wet.
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Consolidated: Soils, typically clays that have become compressed over time; usually the lower layers of soil.
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Detached Breakwater: A shore-parallel structure built in shallow water, just offshore, to reduce erosion and protect beaches by reducing wave action, also referred to as an offshore breakwater.
See also shore structure webpage
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Dead zone: An area or layer of hypoxic or anoxic waters often devoid of fish and invertebrates.
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Dike: An artificial wall used to reduce flooding within a low-lying region. Commonly dikes are constructed of cohesive sediment or stone.
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Dolomite: A sedimentary rock, similar to limestone. See also limestone.
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Dune: An accumulation of sand, usually built by wind and/or storm waves, that exists above calm water level and usually persists for longer than one season, perhaps for years. Through the intentional human-induced movement of sand, dunes may be created or enhanced. Dunes are often stabilized by vegetation and function to protect the upland by limiting the number and force of waves reaching inland. They also serve as habitat for shore birds and invertebrates.
See also shore structure webpage
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Dynamic Equilibrium: A system that is continually changing with all materials entering the system equal to that exiting. In terms of sediment changes at a beach, the amount of sand building the beach is the same as the amount of sand eroding due to waves and wind.
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Erosion: The wearing away of land or a lakebed by the action of natural forces. (USACE, Living on the Coast)
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Fish kill: The death of a significant number of fish in a relatively short period of time. Fish kills can be caused by anoxia, pollution, disease, and natural stresses.
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Glaciolacustrine: The sediment deposited in lakes associated with glaciers. The lakes may occur near, adjacent to, or otherwise in association with glaciers. As with other lake sediments, these sediments are typically fine-grained, having been left by calm, slow-moving waters.
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Groin: A structure that is attached to the shore and projects into the lake at or near a right angle to the shore, whose function is to build a beach by stopping or slowing the movement of sediment along the shore.
See also shore structure webpage
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Groin Field: A set of typically evenly spaced groins.
See also shore structure webpage
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Habitat: The physical area and biological conditions that support the needs of living organisms. Areas with similar physical and biological properties on a large scale are also referred to as habitats. For example, the nearshore of Lake Erie is considered habitat of fish. On a smaller scale, the sandy bottom of the lake nearshore would be considered a different habitat than the rocky bottom.
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Headland: An area of land- typically a bluff- that projects farther out into the lake than the surroundings due to greater resistance to erosion.
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Herbaceous plants: Plants with soft or non-woody tissues that die down at the end of the season and grow again next season; often perennials or annuals.
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Hypoxic: Describes an area of low levels of oxygen in water that can have a negative impact on fish and invertebrates.
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Invertebrate: An organism lacking a spine. Insects and mussels are common invertebrates found in Lake Erie.
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Jetty: A structure used to stabilize a river mouth, harbor, or tidal inlet for improving navigational (boating) safety. Jetties are shore-connected features built parallel to the navigation channel, often a river, which usually results in the jetty being perpendicular to the shore.
See also shore sturcutre webpage
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Lacustrine: Referring to a lake environment or sediment deposited by a lake.
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Lakebed downcutting: The gradual erosion of nearshore cohesive soils in the lakebed by wave action. In this process, the lakebed is irreversibly deepened, often leading to greater wave energy being directed at the base of the bluff.
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Limestone: A hard sedimentary rock of calcium carbonate. Limestone, and the similar rock dolomite, make up the islands of western Lake Erie and are also found at or near ground surface at Marblehead, Catawba Island, and along parts of Sandusky Bay. Bluffs of limestone tend to be erosion resistant, but are not erosion-proof.
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Littoral Zone: The zone parallel to shore where waves break. Lakeward of the littoral zone wind and waves have little effect on the movement of sand along the shore or on and off the shore. For Lake Erie, the littoral zone is similar to the nearshore.
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Littoral Drift/Littoral Current: The current which moves material parallel to the shore (also referred to as longshore or alongshore). Littoral drift can also be the material that is moved along the shore.
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Nearshore Zone: The zone parallel to shore influenced by wave energy and littoral currents. For Lake Erie, the nearshore zone is similar to the littoral zone, but can be used to refer to shallow areas extending lakeward of the littoral zone.
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Nearshore Ice Complex: The relatively flat ice that extends lakeward from the shore. This ice is often attached to the onshore ice which has a more jagged appearance because it has been pushed onto the land.
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Pelagic: Organisms living within the water column or open water of a body of water. In contrast, organisms living at the bottom of a body of water or on or within the sediments of the lakebed are referred to as benthic.
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Pier: A structure extending into the lake that is primarily intended for lake access, watercraft or recreation, rather than erosion prevention.
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Re-grading/ Terracing: Re-grading involves the excavation and movement of bluff material to make the slope of the bluff more stable (usually less steep) than the original slope. Terracing is more intensive and involves the creation of terraces, or platforms, along the bluff face, often with switch-backs to create an easy pathway down to lake level.
See also shore structure webpage
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Revetment: A sloped onshore structure, usually of stone, built to protect the toe of a bluff or bank from erosion caused by wave action.
See also shore structure webpage
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Rip-rap: A classification of quarried stone of a wide size range, typically much smaller in weight than armor stone. Revetments are often referred to as being constructed with rip-rap.
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Salient: An extension of beach projecting from the shore towards an offshore breakwater or island, but not connected to it.
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Sand Bypassing: The intentional redistribution of sand from an updrift area of accretion to areas downdrift that have been starved of sand. This may occur through pumping, dredging, excavation, or other means.
See also shore structure webpage.
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Sand spit: An above-water accumulation of sand built naturally by wave action, often at the end of a landform. This sand frequently moves with waves and currents, unless stabilized with structures.
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  Seawall: An onshore, vertical shore-parallel structure with the primary function of reducing wave-induced toe erosion. A secondary function of a seawall is to limit waves from overtopping the structure to prevent flooding of the land behind the structure. Seawalls may also be built with a cap on the top of the structure for lake access.
See also shore structure webpage.
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Sediment: Material resulting from the weathering of rocks and/or erosion of soils, ranging from microscopic to gravel-sized, that is carried and deposited by wind, water, or ice.
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Sediment sink: An area where the sediment within the littoral system escapes the influence of currents and becomes deposited. This area captures the sediment and does not allow for transport onshore or downdrift.
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Seiche: The oscillation of water between two ends of an enclosed basin such as Lake Erie, resulting from a surge in water level. Seiche inducing surges are usually due to storm winds that persist for a number of hours. When the wind subsides, the surge rebounds to the other end of the lake until the water level stabilizes (similar to water sloshing from one end of a bathtub to another). The Toledo Gauge Station is at the western end of Lake Erie. The Buffalo Gauge Station is at the eastern end. The graph above illustrates a seiche event that occurred in April 2011.
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Shale: A bedrock type, the remnants of ancient muds and silts deposited millions of years ago. Shale makes up much of the bluff in parts of Cuyahoga, Lorain and Erie counties, and is exposed in the nearshore as well from Erie to Ashtabula County.
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Shoal: A shallow area within a body of water, usually due to sediment accumulation that is often a hazard to navigation.
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Shore-Parallel Structures: Shore structures oriented so that their long axis is in the same direction as (i.e. parallel to) the shore. Typical structures of this kind include seawalls, revetments, bulkheads, and offshore breakwaters.
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Shore-Perpendicular Structures: Shore structures oriented so that their long axis extends from the shore into the lake and are not parallel with the shore. Common structures of this kind include jetties and groins.
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Slumping: A form of slope erosion where large sheets of soil move under gravity down the face of a bluff.
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Terminal Groin: A groin constructed at the end of a beach enhancement project to contain sand within the project boundaries. Terminal groins are often constructed to contain sand pre-fill added to a project site or when a beach enhancement project is located near an existing marina or navigation channel.
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Till: An unsorted mixture of sediments and soils placed by the glaciers through direct deposit of material either under the ice or following ice melt. Land formations comprised of till may contain a combination of silt, clay, sand, and gravel.
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Till Lag: Coarse, unsorted, gravelly material caused by geologically recent erosion of glacial till features such as bluffs. Finer materials are commonly washed away, leaving the coarse deposits, perhaps with a sticky coating.
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Tombolo: An extension of beach projecting lakeward from the shore and connecting to an offshore breakwater or island.
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Unconsolidated: Loose soil materials, such as sands and gravels and upper layers of soils that have not been compressed or cemented.
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In an on-going effort to assist property owners along Ohio’s Lake Erie coast by providing free technical assistance, the Lake Erie Shore Erosion Management Plan (LESEMP) is being developed by the Ohio Departmentof Natural Resources through a partnership between the Office of Coastal Management, Division of Wildlife and Division of Geological Survey.
The LESEMP identifies the causes of erosion in specific areas called reaches which are stretches of shore with similar site conditions. The LESEMP then outlines the most likely means of successful erosion control based on reach-specific erosion issues, geology and habitat. The objective of the reachbased approach to erosion control is to simplify the decision process while enhancing the effectiveness of solutions to erosion related issues.
The LESEMP does not contain any regulatory oversight provisions.
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