 Before and after photos of beach restoration efforts, Florida coastline, USA. Beach nourishment is a complimentary term that describes a process by which sediment (usually sand) lost through longshore drift or erosion is replaced on a beach. It involves the transport of the nourishment material from one area to the affected area. This process is often expensive (minimum of $1 million/mile), depending upon the source (and thus the cost) of the sand. Beach nourishment is almost always used as part of a coastal defense scheme. A poorly-designed and/or executed beach nourishment project can result in a severely impacted ecosystem, regardless of how much care is taken to deal with the sustainability of the littoral environment. Once a beach is nourished, it almost always is necessary to regularly renourish it since nourished beaches tend to erode faster than natural beaches. The economic activity generated through beach tourism may compensate for the cost of both capital and maintenance beach nourishment works, but only in a small number of heavily urbanized areas. Image File history File links This is a lossless scalable vector image. ...
Image File history File links Beach nourishment - before and after photos of beach restoration efforts, Florida coastline. ...
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This article or section cites very few or no references or sources. ...
For other uses, see Sand (disambiguation). ...
Longshore drift (sometimes known as shore drift, LSD or littoral drift) is a geological process by which sediments such as sand or other materials, move along a beach shore. ...
For morphological image processing operations, see Erosion (morphology). ...
For other uses, see Beach (disambiguation). ...
Coastal defenses are objects and engineering techniques used to defend coasts against erosion and flooding. ...
Primary functions:
- to provide protection to backshore property
- to increase the recreational space along the shore
- May replicate natural coastal processes by augmenting coastal sand budgets
- Sediment texture (grain size and sorting) is critical for success. Sand fill must be compatible with native beach sand.
Environmental issues: - dredging may cause short-term direct mortality to sessile organisms, modifies seafloor habitats and sedimentary character
- burial of plants and organisms (SAV, shellfish)
- blockage of light in water (coral reefs, SAV)
- toxicity of sediments
- dredging too close to shore can cause erosion
- changes critical habitat for nesting sea turtles and birds
- provides a false sense of security that increase development pressure
Assessing beach erosion There are two different ways that a sandy beach can become eroded. The first type of erosion is the natural response of a beach to storms and calm weather. During storms, sand from the visible beach submerges below the water to form storm bars that protect the beach from further damage. During calm weather smaller waves return sand from the storm bar back onto the visible recreational beach surface in a process called accretion. The term 'erosion' always sounds bad and conjours up the idea of environmental damage so the term submersion is often used for the natural erosion processes of a healthy sandy beach to distinguish this process from the more serious type of erosion described below. For morphological image processing operations, see Erosion (morphology). ...
Accretion (Coastal Management), is the process of coastal sediments returning to the visible portion of a beach or foreshore following a submersion event. ...
Submersion (Coastal Management), is the sustainable cyclic portion of coastal erosion where coastal sediments move from the visible portion of a beach to the submerged nearshore region, and later return to the original visible portion of the beach. ...
Another type of erosion is a more serious problem for beach health. Some beaches do not have enough sand available to coastal processes to respond naturally to storms. Reasons can include:
When there is not enough sand left available on a beach, then there is no recovery of the beach following storms. Seawall protecting homes from storm waves and beach erosion. ...
This article is about the sand formations, for other meanings see Dune (disambiguation) Mesquite Flat Dunes in Death Valley National Park In physical geography, a dune is a hill of sand built by eolian (wind-related) processes. ...
Longshore drift (sometimes known as shore drift, LSD or littoral drift) is a geological process by which sediments such as sand or other materials, move along a beach shore. ...
This article is about structures for water impoundment. ...
Plates in the crust of the earth, according to the plate tectonics theory Continental drift refers to the movement of the Earths continents relative to each other. ...
Variations in CO2, temperature and dust from the Vostok ice core over the last 450,000 years For current global climate change, see Global warming. ...
Sea level measurements from 23 long tide gauge records in geologically stable environments show a rise of around 20 centimeters per century (2 mm/year). ...
An ocean current is any more or less permanent or continuous, directed movement of ocean water that flows in one of the Earths oceans. ...
The submersion/erosion distinction between total sand in a beach (erosion scale) and its position above or below the waterline (submersion) - is an important aspect when considering beach nourishment proposals. The response to coastal erosion should be different between a situation of extreme erosion and one of extreme submersion - even though the visible portion of the beach erosion will appear the same to observers. An eroded beach in a healthy environment may fully recover with no assistance through beach nourishment. There are beaches that are eroding due to natural processes like longshore drift but the majority of problems for beach health are anthropogenic. Addressing the anthropogenic cause of the beach erosion problem is often a better response to beach erosion than beach nourishment. Submersion (Coastal Management), is the sustainable cyclic portion of coastal erosion where coastal sediments move from the visible portion of a beach to the submerged nearshore region, and later return to the original visible portion of the beach. ...
Submersion (Coastal Management), is the sustainable cyclic portion of coastal erosion where coastal sediments move from the visible portion of a beach to the submerged nearshore region, and later return to the original visible portion of the beach. ...
Submersion (Coastal Management), is the sustainable cyclic portion of coastal erosion where coastal sediments move from the visible portion of a beach to the submerged nearshore region, and later return to the original visible portion of the beach. ...
Longshore drift (sometimes known as shore drift, LSD or littoral drift) is a geological process by which sediments such as sand or other materials, move along a beach shore. ...
Look up anthropogenic in Wiktionary, the free dictionary. ...
Look up anthropogenic in Wiktionary, the free dictionary. ...
A common problem with poorly designed beach nourishment schemes, is that sand is dredged only to the visible portion of the beach above the waterline. Like an iceberg, only a small portion of the entire beach system exists above the waterline. If beach nourishment only occurs upon the upper visible beach above the waterline, then the beach becomes unstable and the sand is quickly eroded to fill the lower portions of the beach. A lot of communities have lost faith in the ability for beach nourishment to improve beach health due to poor design of the nourishment program. Politicians go out and have their photos taken on the newly nourished wide upper beach, but when the first storm arrives most of the sand disappears to fill the lower portions of the beach profile and the overall project is declared a failure. Beach Profile Nourishment is a term that suggests that the full beach profile is nourished, not just the upper visible portion. For beach profile nourishment schemes for the Gold Coast, 75% of the total sand volume is placed below low water level. Some coastal authorities are even overnourishing the lower parts of the active beach profile (nearshore nourishment) so that in the months and years following the investment, the natural beach increases in size. Nearshore nourishment and beach profile nourishment schemes tend to increase the community's confidence that beach nourishment is a worthwhile investment. Icebergs at Cape York, Greenland Iceberg at Cape York, Greenland Iceberg, Témpanos, Patagonia, Argentina. ...
“Gold Coast†redirects here. ...
Beach nourishment projects Beach nourishment projects are usually constructed along shorelines where an erosional trend is present that could be either natural or a result of human activities. In those cases where this trend is due to human activities, the project will perform much better if the cause of the erosional trend can be minimized or eliminated in conjunction with construction of the beach nourishment project. The setting of a beach nourishment project is key to design and potential performance. Possible settings include a long straight beach, a project adjacent to an inlet that may be either a natural or modified inlet and a pocket beach. Projects constructed on rocky or seawalled shorelines, that otherwise have no sediment, present unique problems. Pocket beach is usually a small beach, between two headlands. ...
Seawall protecting homes from storm waves and beach erosion. ...
Northern Gold Coast Gold Coast Beaches have experienced periods of severe beach erosion. In 1967 a series of 11 cyclones removed most of the sand from Gold Coast beaches. The Government of Queensland engaged engineers from Delft University in Holland to advise what to do about the beach erosion. The Delft Report was published in 1971 and outlined a series of works for Gold Coast Beaches, that included beach nourishment and an artificial reef. By 2005 most of the recommendations of the 1971 Delft Report had been implemented. The Northern Gold Coast Beach Protection Strategy (NGBBPS) was a Aus$10 million dollar investment into the health of sandy beaches along the northern Gold Coast in Queensland Australia. The NGCBPS was developed between 1992 and 1999 and the works were completed between 1999 and 2003. The NGCBPS included dredging 3.5 million cubic meters of beach compatible sand from the Gold Coast Broadwater and delivering it through a pipeline to nourish 5 km of sandy beaches along the northern Gold Coast between Surfers Paradise and Main Beach. The new sand nourishment was stabilised by an artificial reef constructed at Narrowneck out of huge geotextile sand bags. The new reef was also designed to be an artificial surfing reef that would improve wave conditions for surfing. A key monitoring program for the NGCBPS is the ARGUS coastal camera system operated by the University of New South Wales. “Gold Coast†redirects here. ...
Slogan or Nickname: Sunshine State, Smart State Motto(s): Audax at Fidelis (Bold but Faithful) Other Australian states and territories Capital Brisbane Government Constitutional monarchy Governor Quentin Bryce Premier Anna Bligh (ALP) Federal representation - House seats 28 - Senate seats 12 Gross State Product (2004-05) - Product ($m) $158,506 (3rd...
The Gold Coast Broadwater is a large estuary of water as large as Sydney Harbour in the central Gold Coast. ...
Categories: Stub ...
Main Beach (originally Southport East) is a suburb of the Gold Coast. ...
Construction in place of an artificial reef from hollow tile blocks Ship about to be scuttled to act as an Artificial Reef An artificial reef is a man-made, underwater structure, typically built for the purpose of promoting marine life in areas of generally featureless bottom. ...
A geotextile is a synthetic permeable textile. ...
Uniwalk is the main walkway stretching through the whole Kensingtion campus The University of New South Wales, also known as UNSW or colloquially as New South, is a university situated in Kensington, a suburb in Sydney, New South Wales, Australia. ...
Holland See the National Institute for Coastal and Marine Management for more information.
Response alternatives on an eroding beach - Structural - The structural approach is simply to prevent upland loss and can be in the form of: revetments, seawalls, detached breakwaters, or groins, etc. If well designed, armoring in the form of shore parallel structures (seawalls or revetments) is emplaced on an eroding shoreline, it will satisfy its intended function of preventing erosion of the upland; however, with continuing erosion, the beach will narrow and eventually the beach will no longer be present. Groins trap sand from the littoral stream and may impact adjacent shorelines. Recognizing that there are cycles of shoreline advancement and recession superimposed on the long-term shoreline change, the armoring will tend to occur during periods of erosional cycles. The time required before no fronting beach is present may be decades.
- Retreat - A second option is retreat as the shoreline erodes. This option has been exercised very infrequently along the United States shoreline; however, a number of examples exist. Retreat would appear to be the most appropriate option in areas of high erosion and in the presence of small economic revenue base. Many, but not all areas of high erosion are due to human activities. These activities interfere with the natural sediment flows either through dam construction (thereby reducing riverine sediment sources) or construction of littoral barriers such as jetties, or by deepening of inlets; thus preventing longshore transport of sediment across these channels.
- Beach nourishment - A third option for responding to an eroding shoreline is beach nourishment. This process usually consists of the placement of large quantities of good quality sediment along the water’s edge to advance the shoreline seaward. Beach nourishment is the only alternative that addresses the sand deficit directly through the placement of additional sediment. Beach nourishment is usually but not always carried out on an eroding shoreline and is favored by a substantial upland investment and a relatively mild erosion rate. Beach nourishment has a finite lifetime and renourishment is almost always required.
Rocky revetment at a restoration site along Keene Creek, Duluth, Minnesota. ...
Breakwaters create safe harbors, but can also trap sediment moving along the coast. ...
A groyne (groin in the United States) is a rigid hydraulic structure built out from the shore (in coastal engineering) or from the bank (in rivers) and interrupts the flow of water and sediment. ...
For morphological image processing operations, see Erosion (morphology). ...
A littoral is the region near the shoreline of a body of fresh or salt water. ...
This article is about structures for water impoundment. ...
Alternate meanings: See Jetty (web server) Alternate meanings: See Jettying in buildings The term jetty, derived from the French jetie, and therefor signifying something thrown out, is applied to a variety of structures employed in river, dock and maritime works which are generally carried out in pairs from river banks...
Benefits of a beach nourishment project
Storm protection It has been demonstrated from both field studies and theory that a wide beach provides significant benefits in the form of storm damage reduction. During storms with elevated water levels and high waves, a wide beach performs as an effective energy absorber with the wave energy dissipated across the surf zone and wide beach rather than impacting on the upland structures and infrastructure. The storm damage reduction benefits of beach nourishment projects have been well established.
Recreational benefits In many coastal areas, the recreational benefits of a wide beach can be substantial. An excellent example of this is the ten mile long Miami Beach, FL, USA project that was constructed over the period 1976 and 1981, cost approximately $64,000,000 and has revitalized the economy of this area. Prior to nourishment of the Miami Beach project, it was quite difficult to walk along many portions of this beach, especially during periods of high tide. Miami Beach is a city located in Miami-Dade County, Florida. ...
The benefit cost ratio for the Northern Gold Coast Beach Protection Strategy (NGCBPS) was conservatively estimated at 75:1 for a AUS$10million investment into beach health. The identified benefits were extrapolated from a model of lost visitor nights in hotels following previous beach erosion events. The NGCBPS improved the health of beaches so that recovery of the recreational sandy surface following minor and moderate storms occurred within weeks. Additional unquantafied benefits of the NGCBPS included lifestyle benefits for residents, additional public open space and improved fishing, diving and surfing conditions. “Gold Coast†redirects here. ...
Potential environmental effects There are potential environmental costs associated with beach nourishment projects. These include decreased habitat for sea animal nesting such as sea turtles due to the pumping of sand onto nesting site that hardens making the digging of nest very difficult. Decreased foraging areas for sea birds, and burying of beach flora under sand being pumped in. The cost of such projects can have a political environment impact as well when there is no willingness to continue paying for the expensive projects that serve as only a temporary fix for erosion problems. Beach Nourishment can also improve habitat for sea turtles, sea birds and beach flora. Typically an eroded beach removes the habitat for sandy beach creatures and so renourishment can often be a positive contribution. In Florida there was concern that the dredge pipes would suck turtles into the pumps. A special vacuum cleaner grill was designed and added to the dredge pipes that ensured that turtles were not sucked in with the sand.
Possible settings for beach nourishment projects There are a number of possible settings for beach nourishment projects. - Long straight beach
- Beach nourishment adjacent to inlets
- Pocket beaches
- Seawalled beach
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