Glossary

A temporary fabric barrier placed around a drop inlet to help prevent sediment from entering storm drains during construction operations, while allowing use of the inlet for storm water conveyance.

Planting live cuttings and other vegetation in the frontal openings of retaining structures.

A securely bound, thick roll consisting of live or dead branches, coir, or other organic or inorganic material.

The distance over the water in which waves are generated by a wind having a rather constant direction and speed.

Layer of fabric, sand, gravel, or graded rock placed between the bank revetment or channel lining and soil for one (1) or more of three (3) purposes: to prevent the soil from moving the revetment; to prevent the revetment from sinking into the soil; to permit natural seepage from the streambank, thus preventing buildup of excessive groundwater pressure. Also called filter layer or filter blanket.

The aquatic and surrounding terrestrial environment that meet the necessary biological and physical requirements of fish species during various life stages.

Streamflow between a structure and the bank, possibly occurring because the structure was not properly tied into the bank.

Uses a probability of a given magnitude flood peak that may be expected to occur for a given return period expressed in years. For example, the "1 in 100 year" flood would have a probability of 0.01 or one (1) percent of being equaled or exceeded in one (1) year.

The period of tide between low water and high water. A rising tide.

Level land adjacent to a river periodically covered by, floodwaters.

The width associated with a value of twice the bankfull depth. It is the area including the floodplain of the river and often the low terrace of alluvial streams. The value when divided by the bankfull width is used to determine the entrenchment ratio.

Produced by moving water.

For coastal areas; area characterized by low, herbaceous or slightly woody plants, annual or sometimes perennial (not grasses.)

A shallow stream crossing; the streambed is often surfaced with stone or other material.

The larger and more mature dune lying between the incipient dune and hinddune area. Foredune vegetation is characterized by grasses and shrubs. Foredunes provide an essential reserve of sand to meet erosion demand during storm conditions. During storm events, the foredune can be eroded back to produce a pronounced dune scarp.

The front dune immediately behind the backshore.

The steeper part of the beach that extends from the low water mark to the upper limit of high tide. The beach face.

Bands of mangrove along subtropical or tropical mainland shores in areas of low wave energy. Many of these areas are located behind coral reefs, which together with the mangroves themselves, provide significant protection for the mainland from storm impact.