Basic Dune Physical Characteristics

New Jersey’s Beach and Dune Characteristics

Dunes in New Jersey are mainly confined to a narrow part of the sandy beach. e line of dunes closest to strip of land between the beach berm and upland the water is called the foredune or primary dune . ese development. While there are a few locations in which primary dunes are particularly susceptible to erosion, the sand supply and beach width are adequate for overwash, and breaching during extreme storms. Dunes dunes to reach their full form (Island Beach State Park, located landward of the foredune are numbered for example) most dunes are limited in height and consecutively and are referred to as the secondary dune , width by the sand available from the beach berm area the tertiary dune , and so on. Along developed coasts, and the infrastructure landward of the beach. As a the natural dunes are sometimes enlarged with result, on most New Jersey beaches only a single line of artificially placed sand or replaced altogether with a dunes exists. structure such as a seawall, bulkhead, or revetment.

e shape of the beach on any given day is the result Seaward of the dune is the beach berm , which is the of a complex set of interactions between the air, the flat, dry section of the beach that is normally used by land, and the sea. Some of the more important factors recreational beach users and by several species of include the: wildlife and plants. Some of these include rare, threatened, and endangered species. Beyond the berm • wave heights and water levels experienced at is a sloped area known as the foreshore which leads into site during the recent past the water. is foreshore is exposed to constant wave present wave and water level conditions • action and generally shifts shape and slope between characteristics of the sand • seasons and storm events in response to changes in underlying geologic conditions at the site • wave action. • presence of any artificial structures. e beach profile continues under water. e area roughout much of New Jersey and the Mid- closest to the dry sand is called the nearshore . Like the Atlantic, present-day dune heights reach 8 to 15 feet foreshore, the nearshore is constantly affected by the above the flat part of the beach known as the berm energy of the breaking waves. e nearshore generally (Hamer et al. 1992; Psuty and Ofiara 2002). is takes one of two shapes. During calm periods, the height has been found to be related to the limit of the beach slopes off uniformly into deep water and ability of the wind to move sand higher on the dune generally takes on a characteristic shape known as an and deposit it on the back or lee side of the dune equilibrium beach profile (Dean 1977). During stormy (Hamer et al. 1992). Dunes have the potential under periods, however, sand eroded from the dry beach ideal conditions to grow in height up to 4 feet per year, collects in nearshore sand bars which form near the although growth rates of less than 2 feet per year are point at which the majority of the waves are breaking. more typical. e part of the beach between the breakpoint and the area that is constantly dry is sometimes referred to as In a typical beach configuration, known as a beach the surfzone . e area beyond the breakers is generally profile (Figure 2), the dune is located along the back referred to as the offshore portion of the beach profile.

4 Dune Manual B ack- s F hore ore- s hore Nea Dunes (th rsho roug re Berm crest h br eake rs) Offs hore Berms Beach scarp

Longshore trough

High tide Longshore bars Low tide (dotted line)

Figure 2. Example of a typical beach profile.

Dunes are constantly changing in response to both transport system until it is deposited offshore in a bar short- and long-term environmental processes at a or on a downdrift beach. given location. Dunes are sometimes referred to as reservoirs of sand. eir size fluctuates in response to Winds play an important role as well, with offshore the amount of available sand on the beach berm, the winds blowing sand from the dune onto the beach, strength and duration of the wind, and the storm surge and onshore winds blowing the sand back into the and wave action. Dunes can either be erosional or dune. Vegetation plays a critical role both in trapping depositional depending on the interaction between sand blown towards the dune and in limiting the sand these processes. Sand loss from wind- and wave- blown off the dune. ese dynamic environmental generated erosion can impact the dune directly or conditions cause dunes to shift between erosive and indirectly by decreasing the supply of sand available to accretional phases. On many beaches, the dune shifts build the dune. During large storms, high water levels landward during the winter in response to erosive may allow waves to erode the base of the dune and conditions and seaward in the summer in response to create a vertical cut or scarp (Figure 5A, B). Typically, accretional conditions (Figure 3). On a stable coast, the sand eroded from the dune gets swept into the the forces building the dune are balanced out by the surfzone, where it becomes a part of the active littoral forces acting to erode the dune.

Figure 3. Dune migration due to sand movement from wind.

Dune Manual 5 Long-Term Dune Evolution

Historically, sea level rise has had the greatest impact quantities of sediment, increasing the width and height on the shape of our coastlines. At the end of the last of the barrier islands (Psuty and Ofiara 2002). As the glacial period (approximately 20,000 years ago), sea barrier islands became more stable, vegetation began to level was about 450 feet lower than it is today, and the grow and coastal dunes began to develop landward of shoreline was located approximately 100 miles seaward the beach berm (Figure 4). Within the last 500 years of its present-day position (Psuty and Ofiara 2002). As or so, New Jersey’s barrier islands entered a new phase the earth’s temperature increased and the glaciers began in their evolutionary development as the once to melt, sea level rose rapidly and continued to do so bountiful supply of offshore sand dwindled, causing a until about 2,500 years ago, when it slowed transition from a period of relative stability to one of significantly. Geologists generally agree that the barrier gradual loss (Psuty and Ofiara 2002). As surges and island shoreline of New Jersey at this time was low and large waves associated with coastal storms began to narrow, with poorly developed beaches and dunes that inundate the beaches on a more regular basis, the were frequently overwashed during large storms (Psuty dunes began to erode and migrate landward. More and Ofiara 2002). During this time the coastal recently, human alterations to the environment, such landscape was extremely dynamic. As the rate of sea as shoreline armoring, have further reduced the natural level rise decreased to approximately its current rate, supply of sediment to the coast. Without a natural the waves and currents began to move the sediments source of sediment and to compensate for sand that were originally flooded during the period of rapid removed from the system during storms, beaches and sea level rise onto New Jersey’s barrier islands. e rate dunes struggle to survive. of sand transfer was sufficient to accumulate large

Year 4

Year 3

Year 2

Year 1

Figure 4. Dune width and height increase over time and migrate in a seaward direction (Rogers and Nash 2003).

6 Dune Manual

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A A B B

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Short-Term Evolution

Sediment Deposition for Dune wind and the availability of a sand source. A beach Growth with a wide berm typically provides an adequate sand source and will allow the dune to grow; however, if the Wind is the main force responsible for the beach is narrow, there may be an insufficient sand establishment, growth, and maintenance of coastal supply, which limits dune growth. On naturally dunes. When a strong wind blows across a sandy narrow beaches, beach nourishment projects represent beach, it picks up grains of sand which then move by an opportunity to encourage dune growth that might sliding, rolling, or even hopping past one another. not occur otherwise. Lighter grains of sand are capable of being moved more easily and can travel farther, while the heavier 1133 | 113P3a |ge Pa ge As a dune grows, it becomes asymmetrical in shape, grains are left behind. Natural and artificial with a steep seaward face and a mildly sloping obstructions on the beach cause the wind to slow landward tail. As the dune becomes taller and the down, which results in depositional areas in select vegetation becomes denser, the backdune is sheltered locations. On a natural beach, vegetation is the most from the wind. Under these conditions, growth common obstruction, while on developed beaches, landward of the crest is reduced, while seaward of the snow fencing or sand fencing is frequently installed to crest, growth remains steady. On wide, depositional mimic the effect of vegetation and accelerate dune coastlines, it is possible for several distinct dune growth (Figure 1). e rate at which the wind can features to develop. If more than one line of dunes supply sand to a dune depends on the strength of the exist, the landward line must be established first.

Dune Manual 7 Otherwise the line closest to the shoreline will trap to continue the transport process after the fine surface sand, preventing it from reaching the original dune. materials have been removed. On most beaches, the Generally, the seaward-most dune will continue to sand found at the bottom of the foreshore slope, near grow seaward until the toe of the dune reaches the the location of most intense wave action, is typically landward limit of seasonal beach fluctuations. If the the coarsest sand. toe of the dune reaches the mean high water line, beach use for both humans as well as rare, threatened, Vegetation and endangered species can be inhibited. Healthy beach and dune systems require both a dune and a Vegetation is an important part of the evolution of fronting beach, which may require periodic beach dunes, as it serves multiple ecological and physical nourishment projects in areas where natural sediment purposes. Vegetation slows the wind, causing some of sources have been compromised. the trapped wind-blown sand to settle to the ground. e heavy grains fall out first, as more energy is required to keep them suspended. As the wind deposits Sand Grain Size the sand, it accumulates around the vegetation, e size of sand grains on a beach influences the rate initiating the creation of a new dune or contributing of sand transport and dune growth. On a natural to the growth of an existing one. e accumulating beach, a given sample of sand will contain particles of sand promotes the growth of vegetation uniquely varying sizes, each of which respond differently to a adapted to dune environments. Both the vegetation given set of wind and wave conditions. Fine-grain and the dune grow in elevation simultaneously as the sands will move more easily, remain in motion longer, roots of the vegetation strengthen and help reinforce and therefore travel farther than coarse-grain sands. the base of the dune. While barriers such as sand e result is a tendency for wind and waves to sort fences can recreate the trapping efficiency of beach sediment. Fine-grain sand is more easily vegetation, they cannot grow with the dunes like removed from the beach face and is commonly found vegetation and therefore require maintenance over in dunes and offshore in deeper water. Once the initial time. layer of fine sand is removed from the beach, the remaining larger grains armor the ground surface, e most effective dune systems in both promoting making it more difficult to transport additional sand. habitat and providing storm protection are those in Higher wind speeds or larger waves are then required which the appropriate vegetation is encouraged in each

A A A B B B C C C

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A A B B

FiguresF 6igaur, be.s F M6igaulu, rbe. 7MeAul, B. Mcieeusltiplec dunei esps ec pliduneeas ntofs dpl tuhanatnte spc otlahlonatts cthoeal oalt coonngelgo al nthiozeenng g la tlndwohneg la athndwred lsaiadnreddw saidrde sidsetablsthabled hed of an established dune. dune. dune.

While WAmhieleric Amane Briceaacnh B Geach Gften isf tneant uisr nallyatu ersallytab elissthaebdlis ohre pdl aonrt pelda nbtye cdo bmy mucomnimutiesn iotine sd uone d une zone. ‘Cape’ American beachgrass (Ammophila always be consistent with a community’s beach systemssy,s tasem dsu,n ase gdruonwet ghr porwotghr epsrsoegsr,e musselst,i pmule lstpipelcei esps eocfi epslan oft ps lanwillts b wegillin b teog icno tlo nciozleo nareizeas are as breviligulata) is the primary plant species found on management plan and should be coordinated with the landwalarndd owf athrde offo threed ufonree. d Iunn Ne.e wIn JeNerswe yJe, trysepyic, atly sppiceacli esps earecie sR areugo Rsau gRoossae R(Rosueg o(Rsuag rososaa ),ros a), foredunes (or pioneer zone) in New Jersey (for more ENSP to ensure that habitat provisioning is not BayberBryay (bMeroryre (llMa operenllsay lpevannisyclav)a, niancad) G, anoldde Gnoroldde (nSrooldid (aSgooli dsap.pg.)o ( Fsp.pig.u) r(Feigs u6r).e s M6)u. l t Mipluel tsipleec siepse acirees are information, see the dune planting section of this compromised. importimpanto frotra ndtu fnoer sdtuanbeil isztaatbioilniz atsi oena cahs pleaacnht pltyapnet hatypse a ha difsf ae rdeinffte craepnat ciatpy atcoi trey toain re stanind s and guide) (Figure 6A-C). American beachgrass thrives on througthhr tohheuegirh r tohheoetisr aronodt sa baonvde a gbroovuendn gdr ovuendngedt vaetigoent.a tTiohne. m Tohset mefofestc teifvfee cdtuivnee d suynsete smysst einm bso itnh b oth windblown sand deposits and collects sparse nutrients promoptrinngogm haotibnngigta hat abnidta pt raonvdid pirnogv sidtotoinrgm s totproromte prctiootne catrieo nt hSaoaresne t dhino sFweeh iinc hcw tihnhiceg h a tphpre oapprriaotepr iate from the incoming sand, stimulating growth and vegetavteiogne tiast eionnc oisu eragnceodu rinag eeadc inh zoeanceh. zone. Sand fencing or snow fencing is often used as a means reproduction. American beachgrass establishes quickly of accelerating or controlling the growth of dunes. and spreads rapidly, making it a favorite among Sand fencing performs a role similar to the stems of communities undertaking dune restoration projects. 9 | P9a |ge Pa ge the vegetation on a natural beach. By slowing the wind T rappin g rates of 2 to 4 feet per season have been to a point below that which is required to keep sand observed along densely cultivated dunes. grains entrained, deposition is encouraged. Sand accumulates around the base of the sand fence, similar In natural dune systems, as growth progresses, multiple to the way snow accumulates around a snow fence in species of plants will begin to colonize areas landward colder climates. Fencings of various materials and of the foredune. In New Jersey, typical species are densities have been utilized. However, experiments rugosa rose ( Rugosa rosa ), bayberry ( Morella have found that the typical wire-bound, wood-slat pensylvanica ), and goldenrod ( Solidago sp .) (Figure 7A, fencing with a width roughly equal to the spacing B). Species diversity is important for dune stabilization between slats (50% porosity) traps about as much sand because each plant type has a different capacity to as other, more costly materials (Manohar and Bruun retain sand through its roots and above-ground 1970) (Figure 8A, B). Due to the relative cost vegetation. One of the most common mistakes effectiveness of this type of fencing, it is the type most communities make when undertaking a dune frequently used in New Jersey. restoration project is planting a single species (most often American beachgrass) everywhere within the In terms of effectiveness, it has been found that sand dune complex. Within the dune system, dense and will accumulate and eventually reach a level about diverse native herbaceous plants in the appropriate three-fourths of the exposed height of the sand fence zones can provide habitat to pollinators and other (Hamer et al. 1992), depending on factors such as wildlife. In the beach berm zone, the appropriate limitation of space and sediment supply. In Dover vegetation is native, herbaceous, and very sparse Township (now Toms River Township), New Jersey, a (<10% cover). More information on the type of 4-foot-tall sand fence placed in a straight line parallel vegetation appropriate for each zone is covered in to the ocean was observed to trap concave sand subsequent chapters; however, dune planting should Dune Manual 9

S S DuuneDneuune neFe nFceinngci ng SnoSwno fewnc feincngi nisg o ifst oenft eusne usd eads aa sm ae manesa tnos atcoc aeclecrealetera otre coorn ctoronlt trhoel t ghreo wgrtohw otfh d oufn deus noens ao nb eaa bch.ea ch. TheT hsen oswno fwen fceen fcuen fcutniocntiso snismilar similarly totloy thttooe th stee mstes mofs tohfe t vheeg veetatagteitatoant ion ao nna at unaratlu braela bch.ea cBh.y By sloswloinwgi nthhege t hehwie nwid nvde lvoeclitoyc ittoy ato p ao ipnot ibent lbeowl othwa tht waht iwchh iicsh r eisq ruiueirqeuiudir teod k teoe kpe tehpe tshaen dsa pnadr titpicalretitsic les entrenatrinaeid,ne ded, pdeospitoisointi oisn e ins ceonucroaugread.dg.e Sdd.an. Sdan acdc acumcumlatuelats aroes aroundu tnhde tbhaes be aose ohe fheen cfen, sciemilar, similar to to thet hewa wy asny oswno awcc aucmcuumlautelast aroes aroundu na df ean fceen ince c inol dceorld celimatr climates. e Ssn. o Swn ofewn cfeinngc iisn gav isa ilabavailable inle in variovarious umas matertialserials an dan dde ndseitniesist.i eEsx.pep Eexrppeimereimntse nhatsv hae foveu fondu tnhad tha thet t tyhep itycapl iwcairl ew-biroeu-bnodu, nwdo, odwo-sodlat- slat fenfceincgi nthhaga tthha haat sha a sw ai dwthid rtohu rgohulgy helqy uaueaqluua taol ttheo t shepa scpinagc ibengt bewetewne selnat ssl a(5ts0 %(5 0p%or poosirtoy)s iwtyi)ll wtriallp tr ap aboaubto asut muas much csahn sda nasd oasth oetrh mater materialsrialserrialsials (M a(Mnoahnaorh aanrd a Bnrdu Burn,uun,9 9) (Fig) (uFrigesu r7eas, 7ba)., bD)uue. e D toueue t htoe the relatreilvatei vceo scto-esftf-ecffteivcetniveesnse osfs tohif st hitysp tye poef foefn fceinngc,i nitg i,s i tthe is thepe peost ofrset qfuereqnuetlyn utlsye ud siend N ienw N ew JerJseerys.e y.

A A B B

Figure 8A, B. ExampFliegursF oigurf sd unse b. fen b.caems wamieth seanuned auneccumusl awtisot hnw .sitaandhnd saand accund accumulmatuiolan.t ion. Sand w ccu ate d ev tually re e o t three-fourths of the exposed height of deposiStsan 40d fweet wiccude and 3a.5te feet dhi gehv (Hteurrainllygt oren e adovant ctihnrge teh-ef odunrteh sse aowf atrhde. D euxrpiongs ethde he wiingthert, othf is the fe ce amer, et 1 2). lt ugh r some suubbtle differences in sand-trapping 2004)t. hAelt hfeougche theareme arer ,s oemt e su b1tle d2i)ff. e relntces uingh r s suommmee rs guubrbotwleth di isf fesubresenqcueesn tilny scaunt dba-tcrka bpypi stngorm s ability, e ost importa tor is otal length of the fenncce. Geometric analysis o and sand-tarabpipliitnyg, abeili ty, othste immopsto irmtaportantt foarc tiosr is th e otal lengtht hoaft theroed fee tnnchcee b. e rGme oanmde cturtic in anto athlyes disu one toaen. dW here deposits fo e n the lee o fe ng n Dover Townshipp,, NJ indicate that 40-foot wide, total lednegptho soift sfe fonce ine a ginv etnhe ar elea.e S otudies ha vfee ng n Doverf uTlolyw enstsahbilpp,is,h NedJ dinudniec saytsete tmhas etx 4is0t,- ftoheo tb ewirmd ew,i ll 3.5 foot-hig nc ve sand de os s form dward of 4 foot-high fencing placed paarallrallel to the shown3 t.h5a ft owothe-rhie gwindbnclownv esa snadn ids adbeunodsants, form dwardt yopfi c4a lfloyo bte- herigodhe fde bnaccikn gto p tlhace eseda wpaarallarralld lineel otof dtuhnee ocean (Herrrirington, 20 4). Studies have shown where wind-blblown sand is abundant, insnstalling installoincge tawnic (eH aes rrirmriuncght ofenn,c 2e 0(on4e) .r o Swt uadboieust h40a vfee tshown whevreeg ewtaitniodn-bbl. lowis nse saasonnda li sp raobcuness dgaivnets, r iinsnses toa ltlhinge twice as much fence n 4 feet behind the first fence) traps about twice as muucch sand, behindtw thice efi rasst) m truapcsh a fbeonuct etwicne as much s4an df,eet behind the rfeilrasttiv feelyn clee)a rtr, satprasig ahbt oveugte twtatiiocne lainse ms fucuouchnd s aon d,m any regardless o he alignm nt H r,r, et. al., 1992). regardrlesgs aordf felenscse oalignhme ealignt (nHmamnert etH al. 199r,r,2 e).t . al., 1992). natural beaches (Rogers and Nash 2003) which In NIne Nwe Jwer Jsereys,e syn,o swno fwen fceingci nisg fr ise qfrueueeqnueutleyn utitly lutiizeldiz toed ctoorn ecptroroensltre dnout lnt dheeu gnlareno dwgwrtoahrw da tnlhimd a imnt doaf n mwaagvneea -wigniedn uwdc-iendd e-rosion Sanbdl ofbewnloncwi nsnag nd.n issd.a annd.l sAd.on c Aaonmd deamdodden blyde u nbseedfni tfe oifsri tst ehahisva ettrhha ailat otc trihte ecar rteas tae sb ar briaedrrru toireinr pe gto tho peep laeos ptw lsehev owe rmhalo isg tmhotrim gwh sate lawks oanlrks dr. oriv dre oivne on actitvheitti eheds ur enedlautsnee.d Dsto.u dnDueun nmanee b umaniilpdiunilpgat uiniloat Nni eoinwn N Jieneewr swNey eew.Jwer sJeyrs iesy r eisg ruelagtueladt byed tbyhe t NheJ DeNJp Deartpmaretnmt eonf t of SevEenravEl incrovainrsmtoanle mcnotemanlm tPaurlno Pittreieocstt edioecpntil o(Nyn J s(DaNnEdJPD f)Ee. nP Ic)ni.ndi gInvididuviadlsu alnsd a cnodm Icnom Nmuenmwi tuJienrsist eaiyer, ses e aearsneoc neoanul cwroaeguaetrhadeg rte opd ac ttotoenr nctaso ccntata utshece t the seaNsoJnDNaElJlyPD tEpoPrior rio epdrriou iotcore cthoe mc aommoemunnceti nogcf i wnprgino prdje-boclttsjoesw cinttss ts eainntd eendd toed ctore acrtdeya/nmtaemo/didmicif ocydidh aaifnyg eaexsn ii snet xitnhisget ibdunegan cduhe .p n rAeonfi. l aeA.c nDt iavuicrtytiniv gi type riods deptohsaittthe dias t if niairlyas tirly hfairlyae irly sctore mecto mamnodmn/o ofron or fnco oprar cisvotaatels tcpaorlom cpoemrmtuy mniutineist iies sth ise th deop fd lhoeiypgmhlo weynmavte o nefnt s eoergfa ys,oe tanhesa olf onsrnaeols hswon rofee wsncnl ocfpeinencn gics ito nflag t ttoen ed as limit the amount of wind-blown sand that ends up in the street and/or on private propeperty duringlimit the w theinte ar mmonutnhts .o Tfy wpiicnadll-yb, tlohiws mn astaenridal tihs at ends up isna nthd eer sotdreese ftro amn dth/eo rb eornm p arnidv amteo vpers oopepffeshrtoyre . during the winter months. Most communities simply redistribute the sand on the berm during redistrdiburutiendg o tnhe th we binertmer dmuroingt hths.e sMoprinsgt. cSoommme unities simpTlyy priecdalilsyt, rmibuucthe o tfhe th es asanndd oisn s ttohred be relramtiv deluy rcinglose to communities also try to use sand fencing to create shore in underwater sandbars. If the storms are severe 1100 | Page desired dune geometries. By strategically placing enough, the erosion may extend all the 101w0a y| aPcraogess th e

fencin g, dune characteristics such as height, width, and beach berm and impact the base of the dunes. is uniformity can be controlled. Although these practices causes an avalanching processes known as beach are not advocated, if they are conducted they should scarping, which can result in large vertical cuts in the be included in a community’s beach maintenance plan seaward dune face. During periods of reduced wave and should be coordinated with the NJDEP to ensure energy, the New Jersey coast is exposed to smaller, less that the beach/dune system (including habitat frequent storms and long-period ocean swell that provisioning) is not compromised during the process. transports sand from offshore back onto the dry beach. During this process, the foreshore region is steepened Seasonal Variability and the widest beaches of the season (typically during On stable or eroding coastlines, the seasonal the late summer/early fall) are formed. Overall, these fluctuation in the beach profile limits the seaward seasonal fluctuations can add up to 75 to 100 feet of extent of the coastal dune system. Pioneer dune grasses horizontal and 2 to 5 feet of vertical change. typically encroach on the berm during the summer,

10 Dune Manual Storms and Recovery Small storms typically only impact the beach/berm system and leave the Pre-storm dune configuration dunes intact. e pre-storm beach Post-storm sand from dune width, elevation, and presence/ relocated in water absence of vegetation will affect the severity of the erosion experienced during a storm. In addition, if the Figure 9. Relocation of sand after a storm. beach has been left vulnerable by previous storms, increased erosion is likely. In fact, the nourishments are often utilized as a way to rebuild the cumulative effects of two closely spaced minor storms beach and accelerate dune recovery. can often exceed the impact of a single severe storm. Breaches Dune recession typically only occurs during larger, Storms like Sandy that generate extreme water levels more infrequent storm events. During these strong and intense wave action can generate breaches in storm events, the berm erodes first, which exposes the undersized sand dune systems. Breaches can occur foredune to direct wave impact. As the waves erode the either from the land side or the bay side, depending on base of the dune, the front face eventually becomes the relative elevation of the water. On undeveloped unstable and collapses. During routine storms, most of coastlines, breaches and overwash are natural processes the eroded sand is temporarily stored offshore in that contribute to barrier island migration and refresh sandbars that migrate onshore during calm weather. important habitats. On developed barrier islands, e beach berm can recover to its pre-storm width and however, breaches represent one of the most elevation in a matter of months. Depending on the destructive short-term erosion hazards as swift currents extent of the erosion, post-storm dune recovery can can create deep channels capable of carrying away take much longer. While the dune begins to recover anything in their paths. During Superstorm Sandy, almost immediately, it typically takes several growing multiple breaches were formed in the Borough of seasons for the beach, dune, and vegetation to return Mantoloking, resulting in extensive damage to the to pre-storm conditions. In some cases, it has been community (Walling 2015). When they occur in found that full recovery from the most extreme storms developed areas such as Mantoloking, breaches are can take up to a decade (Rogers and Nash 2003). In typically closed manually through sand placement or the wake of severe storms, emergency beach structural means; however, when they occur on natural coastlines, breaches may be left to evolve naturally.

Dune Manual 11