Rule 1501-6-10 | Definitions.
(A) "Annual recession rate" means the average rate, expressed in feet per year, at which the recession line moves landward. The annual recession rate shall be based on a time period not less than ten years nor greater than thirty years prior to the year that the base-map imagery was acquired. In no case shall the annual recession rate used to calculate the anticipated recession distance be less than zero.
(B) "Anticipated recession distance" means the center-weighted moving average of distances, equal to thirty times the annual recession rate, as determined at five consecutive transects. Anticipated recession distances less than thirty times the "calculated accuracy limit" (refer to paragraph (H) of this rule) shall be equal to zero.
(C) "Barrier beach" means a narrow, elongate sand ridge rising above lake level and extending generally parallel with the mainland shore, but separated from it by a body of water or a wetland.
(D) "Base recession line" means the recession line mapped from synoptic aerial photography, remote sensing imagery, digital data, or maps used to create the recession-line base map upon which coastal erosion areas are designated. The coastal erosion area shall be designated by measuring anticipated recession distances from the base recession line.
(E) "Beach" means a zone of unconsolidated material that extends landward from the shoreline to the toe of the bluff or dune. Where no bluff or dune exists, the landward limit of the beach is either the line of permanent vegetation or the place where there is a marked change in material or physiographic form.
(F) "Bluff" means a bank or cliff with a precipitous, steeply sloped face adjoining a beach or a body of water.
(G) "Bluff line" means the point of inflection where the slope of the upland surface changes to begin its descent to the beach or shoreline.
(H) "Calculated accuracy limit" means the potential error in recession rate resulting from the limit of image resolution and measurement inaccuracies and shall be calculated by dividing a fixed error of five feet by the time period in years over which the annual recession rate is calculated.
(I) "Coastal erosion area" means those land areas along lake Erie anticipated to be lost due to lake Erie-related erosion within a thirty-year period if no additional approved erosion control measures are completed within that time. These areas include land lakeward of the base recession line where anticipated recession distances are greater than zero and extend landward from the base recession line for a distance equal to the anticipated recession distance. Where anticipated recession distances are equal to zero, coastal erosion areas shall not be designated either lakeward or landward of the base recession line.
(J) "Dike" means any artificial barrier together with appurtenant works that shall be used either to:
(1) Divert or restrain the flow of a stream or other body of water for the purpose of protecting an area from inundation by flood waters; or
(2) Maintain water levels in the diked area for the purposes of managing a wetland.
(K) "Dune" means a ridge or hill of loose, windblown sand, the crest of which typically trends parallel to the shoreline.
(L) "Erosion" means the loss or displacement of land along the lakeshore due to wave attack, ice scour, mass wasting, or other related erosion processes.
(M) "Erosion control measure" means a structure or actions specifically designed to reduce or control lake Erie-related erosion of the shore. Examples include, but are not limited to, groins, jetties, dikes, seawalls, revetments, bulkheads, breakwaters and artificially nourished sand and/or gravel beaches.
(N) "Fill land" means artificial land made by placing substantial fill and associated erosion control measures in lake Erie.
(O) "Mass wasting" means the downslope movement of material due to gravity. Examples of mass wasting include but are not limited to rotational slumps, debris flows, block falls, and rock falls.
(P) "Recession" means the landward retreat of the shore due to erosion.
(Q) "Recession distance" means the distance between two recession lines. The recession distance shows how far the "recession line" (refer to paragraph (R) of this rule) receded during a given time period.
(R) "Recession line" means the landform used for mapping recession of the shore, which shall include but is not limited to:
(1) Where the shore is a bluff, the recession line shall be the bluff line. Examples are shown in figure 1 of this rule.
(2) Where the shore is a sand spit with a dune or a barrier beach with a dune, the recession line shall be the top of the wave-cut face in the dune or the crest of the dune.
(3) Where the shore is a low-lying sand spit lacking a dune or a barrier beach lacking a dune, the recession line shall be the crest of the spit or barrier.
(4) Where the shore is a wetland, the recession line shall be the lakeward line of persistent emergent vegetation.
(5) Where the shore is diked, the recession line shall be the top of the lakeward-facing slope of the dike.
(6) Where low-lying waterfront areas are protected by a seawall, bulkhead, or revetment, the recession line shall be the top of the lakeward-facing slope of the structure.
(S) "Sand spit" means a narrow embankment of land composed of sand and gravel deposited by littoral processes which has one end attached to the shore and the other terminating in open water.
(T) "Shore" means the land bordering the lake.
(U) "Shoreline" means the line of intersection of lake Erie with the beach or shore.
(V) "Wetland" means an area that is inundated or saturated by surface or groundwater at a frequency and duration sufficient to support, and that under normal circumstances does support, vegetation typically adapted for life in saturated soil conditions. Wetland includes without limitation swamps, marshes, bogs, and fens.
Five Year Review Date:
Prior Effective Dates: 9/8/1991