Glossary

A B C D E F G H I J K L M N O P Q R S T U V W Y Y Z

ALGAE - Simple marine or freshwater photosynthetic plants. May be single or multicelled.

ANNUALS - Invertebrates which generally spawn once a year and live about a year.

BEACH - The shoreline zone comprised of unconsolidated sandy material upon which there is a mutual interaction of the forces of erosion, sediment transport and deposition that extends from the low water line landward to where there is a marked change in either material composition or physiographic form such as a dune, bluff, or marsh, or where no such change can be identified, to the line of woody vegetation, or the nearest impermeable manmade structure.

BENTHIC - Pertaining to any plant or animal living in or on the bottom sediment of a river, ocean, lake or other aquatic system.

BERM - A wall or mound built around a low-lying area to contain a spoil material.

BIANNUALS - Invertebrates which generally spawn twice a year and live less than a year.

BMP - Best Management Practice. In general, BMP's are measures that have the combined effect of helping to ensure project integrity for the design life of the project while minimizing the potential adverse impacts associated with construction and maintenance.

BOX CUT - The physical profile of a dredge cut. Typically, areas are box cut with a hydraulic cutter head or mechanical clam shell and adjoining undisturbed sediments will slump into the box cut area in an attempt to reach a more stable slope. Generally, the finer the grain size of the sediments, the flatter the slope.

BRACKISH - Pertaining to the waters of bays and estuaries, salty but of lower salinity than seawater.

BULKHEAD - A vertical structure or partition, usually running parallel to the shoreline, for the purpose of retaining upland soils while providing protection from wave action.

CHANNEL DESIGN PROFILE - The proposed section view of a dredged area after slumping. Usually including side slopes of 2:1 or 3:1.

COASTAL PRIMARY SAND DUNE - A mound of unconsolidated sandy soil which is contiguous to mean high water, whose landward and lateral limits are marked by a change in grade from ten percent or greater to less than ten percent and upon which is growing as of July 1, 1980, or grows thereon subsequent thereto, any one or more of the following plant species: American beach grass; beach heather; dune bean; dusty miller; saltmeadow hay; seabeach sandwort; sea oats; sea rocket; seaside goldenrod; and short dune grass. The following localities are currently authorized to adopt the coastal primary sand dune ordinance: the counties of Accomack, Lancaster, Mathews, Northampton, and Northumberland, and the Cities of Hampton, Norfolk, and Virginia Beach.

COMMISSION - Virginia Marine Resources Commission: A nine member citizen board appointed by the governor and chaired by a Commissioner who serves a dual role as agency head.

COMMUNITY - Ecological term for any naturally occurring group of different organisms inhabiting a common environment, interfacing with each other relatively independent of other groups. Communities may vary in size and larger communities may contain smaller ones.

DETRITUS - Organic matter (primarily marsh plants) which while decaying in the aquatic system forms the basis of major marine food web. The organic matter and its rich growth of microbes are fed on by many estuarine species.

DIKE - A wall or mound built around a low-lying area to prevent flooding.

DRAGLINE - The method of dredging employing a crane and large metal bucket to remove accumulated sediment.

DREDGE BUFFER - An undisturbed area adjacent to a sensitive habitat or structure. Generally, the buffer starts at the edge of a vegetated wetland and extends channelward to the landward most swing of the dredge cutter head. This distance has typically been a minimum of 15 feet. The term "undisturbed" is used here to mean "not cut with the dredge cutter head."

DREDGED MATERIAL - The material removed from a channel bottom or other water body during a dredging operation.

DREDGING IN THE DRY - A technique of dredging used where new channels or canals are being cut. The canal is dredged from the landward end toward the seaward end and the last step is to open the new canal to the existing waterway.

ECOLOGY - The overall relationships between organisms and their environment.

FASTLANDS - The zone extending from the landward limits of wetlands to at least 400 feet inland.

FOOD WEB - The complex interactions of organisms in a natural community involving organisms feeding on one another to obtain energy.

FRESH WATER - Water containing no appreciable salt, usually less than 0.5 parts per thousand.

GABION - A container filled with stone, brick or other material to give it a weight suitable for use in bulkheads, groins, revetments or breakwaters. In the marine environment, usually made of galvanized steel wire mesh with a PVC coating.

GROIN - A shore protection structure built perpendicular to shore to trap sand moving along the shoreline in order to accrete sand and thus retard erosion of the shore.

HETEROGENEOUS - Being composed of many different forms of something. Specifically, a heterogeneous marsh is one composed of many different species without any one being dominant.

HYDROLOGICAL - Pertaining to water, its properties and distribution especially with reference to water on the surface of the land, in the soil and underlying rock.

INTERTIDAL - Area on a shoreline between mean high water and mean low water.

JETTY - A structure extending into a body of water designed to prevent shoaling of a channel.

KNEE BRACING - Piles secured to the bulkhead extending channelward from the face to provide increased stability in situation where the proper application of deadmen is not possible.

LINE OF SALTBUSHES - Refers to the characteristic growth of salt marshes at the upper limit of the highest high tides. When present in a line along the inland side of a marsh it often indicates the upper limits of wetlands as defined in the Virginia Wetlands Act.

LITTORAL PROCESS - Those physical features and characteristics of the intertidal area which determine the type of shoreline present.

LOW PROFILE GROIN - Low profile groins are structures with a terminal elevation at mean low water extending landward to an elevation of 1 foot above mean high water, with the landward terminus extending into upland to reduce flanking.

MEAN HIGH WATER (MHW) - The average height of high waters over a nineteen year period.

MEAN LOW WATER (MLW) - The average height of low waters over a nineteen year period.

MEAN TIDE RANGE - The vertical distance between mean high water and mean low water.

MICROCOSM - A small community regarded as having all the characteristics of the biosphere or the world.

MONOSPECIFIC - Being composed entirely of one species or one type of organism. In this case a marsh vegetated by one type of grass.

OVERBOARD DISPOSAL - The practice of placing dredged material on subaqueous bottom in lieu of upland disposal.

PERENNIAL - A plant which produces new growth year after year according to the seasons. In the case of nonwoody plants the aerial portion dies each winter and is replaced each spring.

PHYSIOGRAPHIC - A description of nature or natural phenomena in general.

PIERS - A PRIVATE PIER is generally held to be an appurtenance to riparian property constructed in the waters opposite said property whose use is noncommercial by definition and designed to provide navigable access and/or mooring for the riparian owner.

NONCOMMERCIAL use means a pier which is for individual property owner use only, and does not support the sale of goods or services.

COMMUNITY PIERS are generally held to be an appurtenance to riparian property for which ownership interest in the property is divided between two or more property owners in the adjoining subdivision or parcel. Community piers are by definition commercial.

POPULATION - All of the members of one species within a community.

PRESSURE TREATED - The process whereby wood is impregnated with certain chemicals to reduce or retard invasion by wood destroying organisms.

PRIMARY PRODUCTION - Biomass produced directly from sunlight by plants.

PRODUCTIVITY - The rate of energy storage of an ecosystem or community in the form of organic substances which can be used as food materials.

REACH - A discrete portion of a river, stream or creek somewhat homogeneous in its physical characteristics and upon which there is mutual interaction of the forces of erosion, sediment transport, and accretion.

RHIZOMES - Underground stems capable of producing new aerial shoots.

RIPRAP - Stone that is hard and angular and of such a quality that it will not disintegrate on exposure to water or weathering and it shall be suitable in all other respects for the purpose intended. No individual armor unit should be longer than three times its minimum dimension.

SECONDARY PRODUCTION - Biomass produced by animals grazing on plants or other organic matter.

SEDIMENT BARRIERS - Structures placed at the toe of a slope or in a drainageway to intercept and detain sediment and decrease flow velocities from drainage areas of limited size. Barriers may be constructed using posts and filter fabric properly anchored at the base and/or straw bales staked in place end to end or any combination of the two.

SHEET PILE - Typically, a wooden plank or steel or vinyl sheet used in the construction of bulkheads and groins.

SHORE DEFENSE STRUCTURES - A bulkhead or groin intended to deter erosion of the shoreline.

SLOPE - Degree of deviation of a surface from the horizontal; measured as a numeric ratio, percent, or in degrees. Expressed as a ratio, the first number is the horizontal distance (run) and the second is the vertical distance (rise), as 2:1. A 2:1 slope is a 50 percent slope. (Slope is actually defined as rise/run (1:2 or 1:3), but is generally referred to as run/rise).

SPECIES DIVERSITY - Pertaining to the numbers of different species inhabiting a given area, i.e. high species diversity would mean many different species in one area.

SPOIL - The material removed from a channel bottom or other body of water during a dredging operation.

SPRING TIDES - Higher high tides which occur twice monthly due to astronomical conditions.

SUBMERGED LANDS - Those ungranted lands beneath the tidal waters of the Commonwealth extending seaward from the mean low water mark to the 3 mile limit (Territorial Sea) and including nontidal freshwater subaqueous bottomlands; or lands beneath freshwaters extending channelward from the ordinary high water mark. The upper limit of VMRC jurisdiction, at the present time, is considered to be where waterways reach a minimum average annual flow rate of five (5) cubic feet per second.

TIME OF YEAR RESTRICTIONS - Restrictions which limit bottom disturbing activity during periods of heightened sensitivity for certain aquatic organisms.

WALER - A wooden plank used in bulkhead construction to help support sheet piles.

WEEP HOLES - Holes placed in the face of a bulkhead at regular intervals to allow water to seep from behind the structure and reduce excessive back pressure caused by the weight of the water.

WETLANDS - TIDAL WETLANDS, as defined in Section 28.2-1300 of the Code of Virginia, means both vegetated and nonvegetated wetlands.

VEGETATED WETLANDS - lands lying between and contiguous to mean low water equal to one and one-half times the mean tide range at the site of the proposed project... upon which is growing any one of the 37 plant species identified in the code.

NONVEGETATED WETLANDS - unvegetated land lying contiguous to mean low water and between mean low water and mean high water, including those unvegetated areas of Back Bay and the North Landing River subject to flooding by normal and wind tides.

FEDERAL DEFINITION - areas that are inundated or saturated by surface or ground water at a frequency and duration, sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions.

WETLANDS BOARD - A board created pursuant to Section 28.2-1303.

WRACK LINE - A line of debris, above the mean high tide line, which has been deposited by previous higher than normal tides.

ZONATION - The practice of terracing depth requirements such that shallow draft vessels are moored closer to shore while deeper draft vessels are located progressively more channelward.