Glossary

A marsh periodically flooded by salt water.

Mineral particles ranging from 0.0025 to 0.08 inch diameter; 0.03 inch is the normal lower limit at which the unaided human eye can distinguish an individual particle.

A procedure whereby sand deposited on the updrift side of a training wall or

The movement of sand by wind. In context of coastlines, "sand drift" is generally used to describe sand movement resulting from natural or man-induced degradation of dune vegetation, resulting in either nuisance or major drift. Sand drift can damage buildings, roads, railways and adjoining natural features such as littoral rainforest or wetlands; sand drift can be a major coastline hazard.

An almost vertical slope along the beach caused by erosion by wave action. It may vary in height from a few inches to several feet, depending on wave action and the nature and composition of the beach. (Also occurs on river and stream banks.)

Concentrated erosive action of flowing water in streams that removes material from the bed and banks.

A vertical, wall-like coastal engineering structure built parallel to the beach or dune line and usually located at the back of the beach or the seaward edge of the dune.

Solid particles or masses of particles that originate from the weathering of rocks and are transported, suspended in, or deposited by air, water or ice, or by other natural agents such as chemical precipitation and organic secretion.

An earthen or rock embankment located to capture sediment from runoff and retain it on the construction site, for use where other on-site erosion control measures are not adequate to prevent off-site sedimentation.

A temporary sediment barrier consisting of filter fabric buried at the bottom, stretched, and supported by posts, or straw bales staked into the ground, designed to retain sediment from small disturbed areas by reducing the velocity of sheet flows.

The sediment transported through a channel by streamflow.

A small, temporary ponding basin formed by an embankment or excavation to capture sediment from runoff.

Groundwater emerging on the face of a streambank.

The removal of a fairly uniform layer of soil material from the land surface by the action of rainfall and surface runoff.

Runoff water that flows uniformly over the soil surface.

A pile with a slender flat cross section to be driven into the ground and meshed or interlocked with similar sheets to form something like a bulkhead. Made out of aluminum, fiberglass, steel, vinyl, wood or other suitable materials.

Slightly cohesive to noncohesive soil composed of particles that are fine than sand but coarser than clay, commonly in the range of 0.004 to 0.0625.

The filling of a waterbody or wetland by waterborne sediment.

Natural depression or opening on the land surface which often includes a channel or hole leading directly to ground water; usually in areas underlain by cavernous limestone.

A measure of the amount of a river’s meandering; the ratio of the river length to the valley length. A straight channel has a sinuosity of 1.0; a fully meandering river has sinuosity of two (2) or greater.

This remedial activity (usually done by hard labor) involves grading the slope to fill in rolls and gullies, slumps, and other depressions that concentrate surface runoff. Slope scaling is necessary to repair slopes prior to wattling, brush packing or erosion control blanket installation.

Shallow swamp or marsh with sluggish, slowly, flowing water.

The downward slipping of a mass of soil, moving as a unit usually with backward rotation, down a bank into the channel. Also called sloughing off or slumping.

A permanent grass sod sediment filter area around a storm drain drop inlet for use once the contributing area soils are stabilized.

Permanent stabilization of exposed areas by laying a continuous cover of grass sod. Sod is useful for providing immediate cover in steep critical areas and in areas unsuitable for seed, such as flowways and around inlets. Sod must be rolled over after placement to ensure contact, and then watered. Sodded waterways and steep slopes may require netting and pegging or stapling.

Soil finer than sand but coarser than clay, but not so fine that it can remain suspended in water for long periods.

Evapotranspiration and interception in the foliage can limit buildup of positive pore water pressure.

The measure of the variety of species in a community that takes into account the relative abundance of each species.

A designed surface passageway for excess runoff water to pass.

A tide that occurs at or near the time of new of full moon and that rises highest and falls lowest from the mean sea level.

The type of bed features associated with the slope and bankfull width of the stream. The bed features are generally chutes and scour pools whose pool-to-pool spacing is inversely related to the stream slope and is proportional to the bankfull width.

Long bags or nets filled with straw or similar material. They are placed along the contour of a slope or streambank in order to reduce erosion and sedimentation. Commonly uses wood or live stakes to anchor the roll in place.

The change in elevation of the bed surface over a measured length of channel. It is expressed as a ratio of elevation (rise) over distance (run) in ft/ft..

The ability of a stream to transport the water and sediment of its watershed in such a manner to maintain its dimension, pattern, and profile, over time, without either aggrading nor degrading.

The portion of the channel cross-section that restricts lateral movement of water. A distinct break in slope form the channel bottom.

Removal of soil particles from a bank slope primarily due to water action. Climatic condition, ice and debris, chemical reactions, and changes in land and stream use may also lead to bank erosion.

Collapse or slippage of a large mass of bank material into the channel.

Plant that is rooted in soil and grows below the water’s surface.

Weight of vegetation can, in certain instances, increase stability via increased confining (normal) stress on the failure surface.

The area between the outermost breaker and the limit of wave uprush.

Roughening a bare, sloped soil surface with horizontal grooves or benches running across the slope. Grooves can be large-scale, such as stair-step grading with small benches or terraces, or small-scaled, such as grooving with disks, tillers, or other machinery, or with heavy tracked machinery which should be reserved for sandy, noncompressible soils. Roughening aids the establishment of vegetative cover, improves water infiltration, and decreases runoff velocity.

That portion of rainfall that moves over the ground toward a lower elevation and does not infiltrate the soil.

The part of the total sediment load that is carried for a considerable period of time at the velocity of the flow, free from contact with the streambank.

That area of the shoreline characterized by wave uprush and retreat.