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THE PROTECTION OF THE OCEAN BEACH.

am 3'fAso-X's iu;/'oir['. The report of Mr H!?; r m ( r )e ooH«rvatioo of Hit (>.- m ttouialii a:ul tiro protuctiim of St.. t'liiii' was «ii!>mitted to the uwetins of tiw> rv.«m u Hoard las!, pvi-'iliiig, (-'■Uiisidtvaliuii of ih« report Was (I,'forKil, 'litfi Kpori w,>- of mi. oxeefdiliiijy ■Mil imiKH'taiit Bdln?!., |i> hi- pivlimiimy rntnarfcs lit! uubou'ledgec! the of nil sports nnrl plans v/Mcli tlie Ijmkl bad remvod on the subject, ijti<a v.iijc'li wore re-fcrrr-d to him for coiwkli ratio!). 'l.ljey weni from flw foUowmg .?ewttmi(!ii:-sff«fri (i, M. Kiiir. J4, H. Mii'iii';. |{, iWmt J, H, lie;,'.voids I?), W. 11. Ihiifiic.-.oii (2), :. m j i'. W. iVtr,< |S). Mr Mason's rcpcvrl ihpn goes on t» say. infer alia.— In the iuirriiij ?,?i.of vein: letter Mid Inc. ii.bavti plans 1 b.vo examined the (<;rcsnore and Sandhills between St. C'l'tir and Lawyers u.wrl Uiysdf !ii'r|iuniitp<i as far pflssiti.e wiih the !ir>Hu"il features u)ttt prcVflllil'lg CnK(lifjQt|-a, Ohr-OVVdti'lllS (s'W'O also Ijseii extendedv.v3i\y;ud.'4 fiom SU CMr along the/'Oiv?:i. to Brighton, hi order in Meerlain what chafes <j{ anv ) have lata pbre over this pieee al cimt within uiute or <1/ fi itilij periods.

JJeiore uunu an examination of the raring plans ami re-ports sitbniiUed I de-iire to n«to M few poictH eonn.ectcd with xji r.ijud bejjone,-, and to dr.'suies brififly, iij the absence of pliV.sical fturtly, the conditjnj.is ;ip-pst-NHjy preuoiimiant at ib Occ-an Ueicti nml St, Clair.

ConseS of Clraijoe in Sand IJerr':,;! and Saiujfuils.—lt !S ob?M-v«i tivnt iii nil sand tactics mictual'.oiis in fonji and creitour iit «%h .and low wiUor inevitaVry oceiir, dejieiid' iil;4 chiefly upon t-h.o decree of cxpn-iure, recj'trrciiy meteorologfeijt cliav^os f eiid tije v:triation in strength and (Urectkn of tijn wav.r' force and .of the caastal current. Thesff agencies pioditce either ioea.l inovomei;! ;u,id fnn : :spor( oi sniid front 011.0 portion of the bea.idi to i,i,n-qt-heri ?)?d ;fit>';in.ent or tf;i' sifj;jj-y •of sitnu froin tliv sen, ptomotiug .?.ometimes more, or Jepn permanent, hut gep<-riiHy of an evanescent character, the tendency beiu£ towards thii assumption of its stale under normal conditionf! of wmd. atid weather. Usually a Mate of practical is attained when Nature La left to henwlf. ]h\\ -,vith the increase of sett'eniont along th.!co,i»l.s Jof niir corouie?. marked changes ki'Vo talvcii ■ place in the sandy shore formations I have noted in the foreshore over tat'"? portiOns of the \ ictovian coa.s't froin Cape. Kofthrmibc;rhrivd to Cape IJowe. On the soul hern : coast of thai Slate, the rand dunc.7 are steadily growing and extending inland hi places, while 011 tire east coast encroachments of the pea r.lO qecin;vui? lietween Corner Inlet m\ the Xn?et.j'-mile lieach. Atid on our own coasts aftfltogoiw idiaiigeft ii.ro in proves*. Mv C. W. Adsuis, then cliief suvvuyov at Thmedui, writing in the Otygo i)aify Time? o-f llfh dune, alludes to change.* at. Post Molynenx a;'id ■ ii#ar I'aieri -Vonf.h. v.-'/fiv c-Aten^iv'i l ift reported us ))loce. Aiitl we liav. 1 , p>mi^ lav evidence in the Hlteratioos visible bcUvoe.ii Bfighton and Head, In ihe nei'/h" bau4iood of Crrcen and .fiawyer's Head saiul is acc\rimViat : ng, while Ihe result of xhsis observed nt S#,. Clair. It is cvidcrd to anv olipcivev Uia.t c ( hiinge.s are largely ujnon the dishivbnnee. of Hainral from i]ie landward side, brought alrout bv the advance of scUh-inont nnd The r-irova l of til* frini™ df forest, biish, or pcrttb coniigu-' 01m to the const and saMdhillsj the of fh-c patural smid by eaitlc nrd tvpfli?, a.)ul the breakmg of the ?and np^ 1 : hy thf sainc agency may be as po* rt vt in protlucmg the \tmle:-dvah!e fhnnoes afoji« our coasts. Deilhis pneciflrally with th fv D'unedin t!>o present iuntabiiily may be countered due tft— Aiternticms to natural epnditionp fffixn t'ho bndwa.vd s.ide by the of the frlntre of' vcc'Matioji, e.-pecfalty at St. CJrir;-ib) loosening ftnd desh-uciion of ssmd tivrisscs by cjittle a,iid traffic; (e) rnpiovnl from Hie honeh oi sea wr[!c]c,- marme doUris, driftwood, etc, (debris of even* ;ii:l s rar,!vr{:;!>}" i-i nrov-i'i'tirff the triivei of dry saiid); fd) brealfing up oi the sand crust by ItJiOic; lk<i saline crust formed in dry weather whero saml is exp&sed to the ocean spray nud the rcced'ng wave prevents drift to a pojir-iderable exUmt: /c) i'-rlifieifll remove (if sawl, Bt, nuil ?ifttsAelburglf, (f) variations from seawards in the OiijiUni! wave acjion, c;'iived by alti'-i'tioi;-?

gftcl T&movai e-f yorlr-i ?.t St. fbir Bntlis. tl i 5 much txr bo vrrvi'it.n.l thot fl)p vocr.Uy 4ioU upcu wi.iif!) fbo }m\\* arc fpnuecl Im bce<i i-nterfered with, either by the remow] of locfts of by cx:':r.vr.(iftnp. without iiutinvo fi<m being givoti as io lbe r(iS.\iH of action in uiuMiny 'he tretul ?.M forte of the. ?r.a m mhm uvatbon upon the fo;ril<nwir? betiAliFrom ifc.~pse*ion \ sm <i>f nniufrh 1-list ditv-ilTg the prcvnlenco of heavy frcsir-tly and :;ouihorly wen-llicr {»!■? nish of w.itrr oyi* the is greater >?ow 'luui before fbe or \}\o_ b.ith*. nr.d. acUi).;' o-a lb o ' eh obliquely, drives the sand before it, tfkling nutenany n{ U»u' : : fbc "ivrcfAM of PwvftiKQg —U- is to ijo rcer->fted that iso full and ctntrplole MiryV ii\% (jb^i : vi'ition t > on (\\p- force and direction c: inshore mrreni.--*, s.ni'ml movements, etc., i- 4 , vail* .able ;h prf-limiiHU'v to the fo'riirtiof iwy improvement Kliciii-?. Currents: Tlie tU 1 .- riiira.lty Sailing Dire el ion? {soe 2(t'7. frlh Kd.) anfl lit Polio's eKtelrd otev.*tta

bwflr mil !h» general statement f'aat tlu 1 foiiß'al currents arc rt« the coa?t casi.vrjy, and. Hint tlierofaw within the limits of kw.liifig strs, which i:i tiliro of :-U rni may esfcend out to tlstsi- fathom lino, Use sandy bottom :? iif molitn iii the same (Jn-rr iinn. Exposure: It. wy 're eoweM 1-liat flic expo aire between St. Olaif H.t.Ml Luwyct's Head !1 not tlir same /.mder all circumstances. fu westerly to southerly we*;!** t'ne St. Clair portion of the Wh is uwlfl the lej. R.i the reeky bultfwses to the tn-st, vthicb r-c! in deflecting the coast?.! t»uvrent seawards, ami altering the direction o-f the wave motion, so that during such weather the above twrtion of the btatrh 15 more of less sliclk'feil front the filt! force of the sea. From Jti- Petri:'? observations it would appear as ii snob infioiwea were felt tlirinvrli two-thirds <st the dit'evm-.o from ft't, Piair towards (lie Central Halt fy, a! which dirtawe the full force o! the s ; a j? eiicouutem! with Jufrfcsed sjml Jeposil. Si'tiil Depnsitv-On» awA el early eiidrav.mr to arrive tt r, of the conditions muler which deno=iJs are formed ic any Bartievdar locality,' before iti'snipting to a : Skt car retard Xiitnre in her work, anti ihe datu io hsnd a ml observations mads should lie fuJiev and more extended, before the exact mt;l lines tor pcitnaisent ivorfer. are laid down. 11l (lie ease under eoM'fb'ralion we. leave to deal with the two <W* of «»»d dwosiU or (lrn-ils—via., wsHer.lnvne drift ami wiuil-linrne drift, llw quantity of the latter etojicmJing upon tile supply of the first, Walor-Borae Mt-.-As already uotf.d., the drift of sen sand up the coast, being lifted from the bottom witln'li thcftreil of broken rater, and transported laterally by the current close ill or off tho shore. depemling upon th,e. force of the two and the character of the roast. Oiiiwitc a bold and clfffy feast I lwvc ibu iI.Iv found the baufc of drift, out front the foot of the cliffs, (lie distance varying' directly as the wave force. Facing a sheiviug'or i-anJv shor; ths drill may be .{timid class, to, in" rough weather frequently forming a rid; i. parallel with tiic shore, tind np.prtarliing nearer thereto its the sm moderates, until with fine wrcithpv it may be heaped* up above low-water mar![, inilil finally by the waye action hicqrpwMl : to form tiio bench at high-water iiKU'fe, This : process can b? sre:, in a-::t;o,i very li'-ainU* bitivi'cu lawyer's Ilcad ami Iber:",:';!:, where the btt(klin»-n;i of the ißaelt from Rewards appears to he greatest. In the ra.se of the beach opposite Si. Clair it Ins h-cn l-'d oil! Itiat the rocks to the w.istwijrd tend to deflect the ciimnt and flu; Ireml of flic' wave during southerly am) viisierly WeatlKT, when She drift of sand from Peiiwiirds- m::-t nec 'fsnt'ily 1» gi'eirter thiin at other times;. Ilul ijli(:h drift will probably, hv the agency awl also by the Itrnvkr v;,ive rc:'''|ioii:i a! <ueh sat»ons, lis kept iveil ehn t v fl f tin- shwv a dUhince m'jitli of tlie i/:c!is, while the waves humnsm;; on the l>M<-li oliliuu-ly cense guv Piiwi th.'if. may he .vaplißil ij;> („ wcrii Sivey freu'i lite iiivht. T'ndvr prifHcr enndi. tious su-li action wow!,l prahitiiy not heve proved delriniental to stability, i;he Send d, : . posiird duriug' fine nortiierly or (a»t.\r!y weather, to»etlier with wind-borne drift, wsukl have kouo to maintain the. nnlura! bidance. Supply of Waier-hoi'ft.i I?,;:-. I e;!niiot sac any reason to fear thn! the supply M WRfirbortm d'-.'ft is not its p-eat ns in t.he year* lirfore Sfttleineiit, or Ihet (or ye.tfs 'o eonie. tl'.ere will be any <lir.ii«utioii Hi.-■)><'»!. 'ill-? sands hrpnjht Sown lij- our fiver,-; ai'fl stresni?, such as tin' Molyneti:; and il-at'iimi, ti'ii- never, eej.sifig disintesKdien aim erosion «f the cliffe shore, shown nc;u' home at: the clilT-- >cuth of JJr Caivi'.l's resitUne:.', and the (listnrbaiiee of o'd deposits alont; ihe es'ist to the south will pu>Yide a more or less r-oussa-it, supply, t-'.' eve seuthc-vi'v "file niiM hritef ifa of d-'i r t opposite the b?iieh, h Wiriioti of whiet; wcrliii-g iiisiiore a; ihe u'of-s dov/n, will ren'aee the s:i : .t£i cavriefl awav oy iiic mmc gale iii'tho costv.r ■■■■■ WiiHi-liertie Drift.-Tbe dwirilmiioH of u„ hs.!;'m- dritt, as wi-15 ]( s (.-oiiti-t-mei:.} within limits. rr(|ni'T-cO'isi-h reiiiKi in ill* t.'ork j '.'o!!S' , iviii t .r ihe and foreflio-,-. I I tliWi the Itfwlem.v »: (he Ocean B-a-h I--, a- 1 a whn'e, torards a(?';n«,;:!ti(m. but ai !h" same ! til?!' 1 it is apjK.i'etu ih:i! the bfaeh .=i;fT-'i-:- fi'sin | liii'-rjna' distribe.'ißii «f the ss'luly (spoil, 3V j pveilfli'iifltilU'e 'n (it'i l ill tlie onri! nmst hf i he ill )h.- obT.'tje.n of ;Ilf f,i-,val!i,l» mcA {WW M' C\>it t/,«xnU Uwivf's ' Ilea.;!—unh'-- :-e.e:!ii-ifd by te.-> ,-flrrivv ci r-n- | rir«nm«nl. Ouris-K tbr ;>rvv»'rs«i> wimi* | .V(.m jiortif !« «4. i!:-' t-jad-knif Wit d;-! pe-itfil in the bight r.f Pt. C'air v,i!l hot i K< ce.sv.,:viiy he ?ll (li-phi'-riT !,v vi- of fonal ] v.'.tc fro® opiuisiii.'; f|itar'ors, ri«m? to I.J.if: cow- ; nsrative shelter afeite] l,y th«'mr»viin.li.« fit ii.vi-jill. i.'-j v.-vvrli a.-'jt;s In pausing j ■''In-tfji.'V die e>J:iii;:' in iveen! of | erifiiniil bi.i ; h f®m 'he ; ivi:(t bills nia-V n <l,! al'ii" the westerly wilids J lucre sciino hi :'ii; iii.vtjS thjW in | (otnter yeti®, irtjtl thus ha-teis the proce-? of ; de;ind;;UOU.t I ® in«la«l in (he eiviumii i liwt til? ytiuiit! fmsoa to the kutiks «t !

= Clair is the displacement of the wind-home drift from sonic of the causes connected with Settlement, and no doubt helped by the removal i pf the locks at the baths, erection of sea-oppos-ing walls and efflux of drainage. UepnrW and Schemes.—'The reports submitted are addressed to various persons and bud it . j , and cover a period extending from July, J£9l, to August o{ tliis yeat. Th«'y cannot in every ens? be considered complete schemes, the \vrit»rs no doubt b;'ing coiifiurcl by the tenor pi llunr instructions. In only one instance h.is ii genera! schcme been submitted in a competitive manner, and to regard the remaining reports obtained at different time? and under diflLieiu instructions in the same light cannot be intended. The location and character of dcFH'n foi ii .sea wall or embankment distuned in all the .reports, and appears the only question that is generally treated with foil' Retail. J have therefore (-nd'HYoiucd in the place In concisely define and coinnave their essential propositions dealing with the general maintenance and conservation of tip domain, and in the second place to indicate from submitted designs the ckss and diameter oi sea wnl! which, in mv judgment, would be the best for the board to adopt, ii HU'.h were ffltind (o be necessarv. Addendum.-In the addendum to tliii report will be (mind Home notes on the maintenance ©f tin l Ocean iJejndi and fuller oetai'.s of con.sci vat ion opera iioini, loi'ether with othrr co';nute iiifnrmation which may aid the board in the initial inn of imnrovements and management of the Domain. Operations.- The subject will b? best deal', "wilh under two head.-' —viz.: (a) Projection and oonscrvitt son oi Sandhills ap.d beach; (b) protectioji <»f St. Clair and re-erection of .sea wall, fn) I'iolcclion and conservation of .Sandhills Ist. Protection. The three methods suggested ii'i the reports as applicable for raising the k'K'h and seeuriiiL' protection to the Sand-

I hills arc -(a) Arrcsl of wind-borne drift by I meaiiH of wind brakes inshore of high water [jjuirk; (h) arrest of sand travel generally by I means of groynes extending out beyond high[water murk; (c) protection of Sandhills and | J' Istt by mei'iis <»f sea walls or embankments, 1 with or wilhout protecting groynes, (a) Of the ■ above methods there is no doubt, that the 4 first (a) is tiuquestionably the method that ; Hiiothd primarily be adopted or tried wherever ' favourable condilions obtain, such as immunity from inundation and of exposure to sand travel. , ?'![' referring to the breaches in the Sandhills between Musselburgh and St. Clair, says: But I will point out the proper principle tp adopt in this will be to endeavour to induce the Sandhills to extend from the beach outwards. And this expresses the views 0! Mr JJutHieson and Messrs Mirams and Hasher on the sumo point, with, which I concur. The success oi the fences nlrfadY erected at Musselmrgh as an pnrnest of what may be ixpected by their future extension, and favours the belief that the depression forming the lagoon Diay thus be ultimately filled up to a level Miflicient for (he growth of vegetation. The barriers across the depressions might with advantage be mndc of more substantial materials t miu 'brushwood so as to last for some time and sustain the effect of a possible subflitrgcncc before llio j.and has had time to amimnlatc. Spb clause IS of Messrs Mirams lUid Ussb.cr report, (b) Tile b-'ecor.d method (b) of promoting sand accumulatioji by means of groynes extending out beyond hi«b water marl; is evidently peculiarly adapted to '.lie conditions prevailing at the Ocean licacl'., and ifi places v.ii"re the first method is not annljcsole, should assuredly be tried before attempting the construction of sea-opposing iviills. The raising of the beach and consequent retirement of {lie high '.v.V.er mark is iiecessarv to prevent undenniiiiiig o! the Sandhill slows Hie stability of which must be maintained will I lieu* surfaces more or less "fixed" before grass planting t'.icivon can succeed. The portion of the beach between St. Clair and Central Lattery, where the slopes oi the Sandhills are washed by the s:a at high water, might b" rniscd by means of the groynes referred to in Messrs -Miranis and Uasher's report (clause 1G), and Leslie 11. Reynolds's further report, •l/iO/98. These consist of framed timber work or hollow cribs filled with stones or of stones a.one. An extensively used and safer construction of grovne for exposed positions consists of a row of piles spaced a few feet apart with or without bracing and sheet piling between. This latter cla«s oi groyne I would personally bo inclined to advocate for the situation ill question, but al the same time thinlr it advisable for a crib groyne to be tried in t.'c first place as a test of its strength and efficiency in withstanding the wavo force to which it may bu cposed. 1 have not the slightest doubt that Hie cons! ruction of groynes as suggested would, yiiovovoi placed on tlio outer beach, slop Jurther encroachment, and build it up by arresting the travel of drift eastwards. One

may point to the efficient protection of portions of the Kentish eoa»t, the coasts of Sussox, Norfolk, and north of the Humbor. brought about by analnsous means. And in lite Fame manner no difficulty lias been found lii stopping sea encroachments in the State ?> V c i,1 r !n- Swm Islnml ' a{ t!;e "I'rance lo inrl 1 lullip, lost ncrcs year by year, mifii protected by groynes, when accretion comn:tineed, and is still in progress where thus protected. Indeed, Uje trouble lias been to pJevc'iil snnd accumulations owing to the effect produced by numerous jeltys and niers rui> out from the exposed sandy const. These interfere ftith the natural movement of the drift «y pciing as groynes, resulting in a making of tlie beach and decreased dojiths of water in the vicinitv of such p.cr". (o)The third method (c) of opposing fuitiin- sea encroachments hv menus oi a spa wall is one thai, in mv opinion, should traly l,p resorted to when the conditions are stwh as to admit of nn n11,»,. „n i; i • .i.

,„ ,uui:i, mi oilier anernative, winch no. so ;n the (i ic o of the Ocean Beach. The s.oppa.;e and l,ohlin s of Die sand continually Muphwl ii'Oin the Pea, and meanwhile drifted hj wind and tide, are all that is necessary to hl.tld „p maintain the beach, a result i Inch no wall in itseli could effect. The t»ndency o; a wa 1 woil'd he to lower the beach Uttifss fian..:ed by groynes, whicb would in turn hy eneomagins .sand deposit, probably render f. ?, unnecessary. I am convinced that (i» and (b). already described, will ceomphsl, the ;]Mirf< , ol , jpfti aml m t ' hpn ,_ Jflio no. m-onnrecj to arlvocato walls or rmbanlrUleuts as a delctice against sea encroachments .1- the Oc'.m Beach, the effects of which riav hs serious and far reaching. y lieehinnfion and Conservation of (he Sand hints and Sandhills.-The subject :s touched \f!r"„l" n I ' 0 ' ,8 ' 1,1111 19 of Messrs re P° ri ' n,:d R,£o by Mr wl rl i t, 1 n"'"' 0f '"' s re ' !or( ' with \Mtieh i lui;dameiital!y concur. It seems lo me necessary, however, thai Eomctbin» more than a hare outline of such operations is neccssa:y, and I have therefore treated Ihe matter Milium. " nd l,orlienUnrs mor,! t,,l| y •» Proteelion of St. Clair and Ke-ereclioi, of Sea H o7^cli ro^' 0 " °' , a " E wa " for eifl !m II ' ' a ' 1(1 - tllo ° C<im Bench is ports d.oico'of be the only uS wh'Tthe Jo,rd lequire detennnialion. As before stated, there are reasons for counselling delay in the cmistnietion of walls until the bca-h has been vM T ["T 1 ™ 1 - *'» tlot'W the comoaralively sheltered position at St. Clair would be time lavourable to the maintenance of a wall tiian at any other pari of the bench. But T hold strongly that ihe raising of the beach hv the Ilitcrrrotion of sand drift o" oilier means should E 5 ? 6 "ti ° f " ,e 15 splanntlc wall. Designs: rite various designs submilled pro,or ,valls or embßiibneiits iu timber o1 "' nn(l n,^ K witll or m.u.l f! stone "prons. The efficiency of anv fonnlil ' !>C "i "P"" stability of ■o a io,i. and as sand inrnw one of the b;s|. T' s 7 h ? n T*"" 1 1!ot nllmv « l 10 ''.U)e. the design l,r«t ( aicu!:,led lo maintain h,s condition, other thint-s being eottal, should ■Ue he preference. A loose rubble or stone 1": \ n "" f,l r ]y i vn EaiK '- n,l<l expospd to its , fru.p <0 1110 WIIPH 01 waves on 'I slonincr han/ili r u,Id certainly s i„, : thr 1"!T 1 ( 0 "' c 7 i l . tll ° ■ a " ( 1 Iwl. thus allowim; Ihe foundation to be waslird away lhroit 2 h !f 01 il » wa,L Wilt" this danger 5- avertfil In- of fasoinp njpj i ves-s or clay puddle, I should hesitate'to ■ (-rontiuend u-orlis of this diameter as suitable to tin. eondi ions of e-oosnr: and formation . WO d 'or, Thf 6h '" Cl " r * >:\ , ad'.ocst" won.d present a solid stir- ■ ri to Ine sea, and secured as far as possible ,™blnlhn r ' , f 1 " i, ' ? , rrt "" " ,r ""<1 notation of ,rcsh and sat! water. Tlie d»si'jus in conoreli'. fimb-i. and ma=onry fulfil he eo-'dit.ons mote o, le,s. Wall in Con- • et . the concrete monolith proposed bv Mr Uii-.cheson IS linr.ne.tior.i.lily (considered'as a V J.J- defence) th" most satisfactory design, and i! built and placet would, in rov op,l,um, oive the nmmimn of security at the i>; »">»"» of co-a Mr Untcheson roughly 'i^!t Pn?l ,or t0 " ®f ">e above wall at R „ m v; | !le |, 9l rajos ■ » labour n-.,:l malr-rial, would have to be ..•.■rrawl to y : , lvi ||, an 3 |, otnl| . p Jm .., in.it.on of osi,|„n P( li. and wing wall at ForMUV roa:l, l, vl „o ln „ !]|o |n(a) n ,„ Jro)£ i lnn . to cwnditnre up to itwn. The difficulty and 11 'onftriK-tinjj the wall the level priced wi ] no dc.ubt be gnat, and. moreover. T :1 ' :il ' " r.ttirh will lie gahjrd hv cf If'l being required. '1 C Pi:il "' 5 in are fttriV ? , '' Borr llr O'Connor V ,no!^. ll f^ir sis i nf nrar:y m,ic:!i ™ 113 . r ";«"'at'on of concrete in bass, and r''" n-, , 'u '' lOSO ■ (lf b-Wl f U 4 " r n ' ~ r;l? l 1"1 sai " l - file only difference { lie-.":enn t,i» dwian. i s (heir I,fight end ioc.,. I """ r-' lt ! to I'ish-water ma,'!; as it ! V; Barr 'I'MV t:p his rencrt. Wr ~ 1.11,1, r. ,01,. nation, with an auron of rubble ' iw-t. I do not consider thi; design at all ! ''' ~J', ,J ' iu question, whore h v o foimV.ioi, j, n, f cllicf ronsiderai V.alls: Alter,,alive schemes for ■ ■■rr wo:! are fnrai?l>Cil by Mr Bait. The | estiina'e given for the wall is (;!SlO. For s wall ! PXW«I to wave action it would, in m < oninion i lu necessary to put in double sheeting, mid i i-:iry the same somewhat deeo-r. A fascine j n-,(trass under the it,me; forming the apron would givr greater security against ttnder- ! mining ai d escape of the filling, Tb» adop- ; fio.il of tiii. above sugs"sfio;,s would inrreasn bo--o rriiniatc by e?.!Ji). ni»Mn* a total nf -I'cromnjf'datines: T submit for the : considrralioii the design in concrete by j Vi. 11. Tfutchcson, and "scheme E" in timber 1 <iy ,ur B.irr as. alternative design? for sen wall-

should such be required. Concrete: The wall in concrete has (lie merit of durability, strength, end stability, but its costly; estimated cost, £1303 for ten chains. Timber: 'Die timber wall, while not so durable ns the above, will, ii built- oi approved hardwoods, be »oorl for 30 years. f consider it a safer and move stable construction 'than the various design* in masonry, and in the event oi damage" or under-mining wouid be more easilv repaired and made good again; estimated coat, .£'2llo lor ten chains. In the event of the raising of the beach by means alieady suggested, a timber structure similar to the [orcTCing would form an admirable brcMuork foi the esplanade, with the Dilution of the apron of stones, t wouid not favour a lower level for the esplanade than provided for in "scheme K," and have therefore allowed a sum of ClfOO in tho table ot expenditure, as provision for nn esplanade wall of simiiar construction. Advkxduv. Restoration oi the Beach at St. Clair.-WY-U the rwi'ptiuj] of the poiJion opjjo.silo St. flair no appicheiisiou need exist- as to the stability oi the heju'Jj injilcr prevailing conditions, in whim llio v.'iivc? B):<?r.d themselves grradunllv upon tne sandy slopes, leaving in the aKcrcgsite luoro th.wi they taki» away. In the rase of the frontage to St. Clair, this 'i-'si'esate IS evident';,' not sufficient to make up the loss from other causes, and the question becomes: Can the supply be increased from seaward ? My own experience, and what IS being done elsewhere, convince me that it 1 'J character of the works of any scheme one could conscientiously recommend would bo auch that, while offering a minimum resistance tc ho imjiaet ot the rea, they would intercept and arrest some, portion of the water-borne drift in Its progress eastwards, causing it | 0 work mlo the bi«l.t at St, Clair and build up die foreshore. (Iroynes: To accomplish the above I would advocate the construction of a, groyne or groynes inn out from the shore or oe o the .Sandhills until the desired effect, is obtained. ihc projection of such »rovne Cei tr MM " 1C P f, rl ' lUy rontl lowimls (Ii li.Vt r y wo "' €l intercept portion of tho v i l 'm 3 ? 1 ll,p sllorc furllier £ T ! llslr, m ? P«e "P s«ch drift along .lie shore to the westward of the groyne. Jitlj gioyne• lam inclined to k-lieve that-'one giojnc would sn /n ( . P (o rp ,| on , ( | lc beac|i i„H„ . ~g ootl, I >'P C wo » l! l ho that of ii jett-j consisting of a row of piles, sa ' v 10ft apart, with a parallel row, sav, 20ft apart for Staying purposes and to carry the truck for the pile-driver. The piles to be braced mid waled or shcet-piled between. Heavy rubble Ot bouldors obtained as suggested by Mr Hrynolds from the boulder beach could belaid along the oilier portion at a later date if required. lie distant.' out such a groyne would require to be taken would probably not be further than into 3ft or 4ft at low water. It would be belter, however, not to define any deliu.te length of structure, but watch tho rcc of each completed portion in building up '""fore extending it further.' it is manifest that the accumulation of saml beyond what IS iieeuful to maintain the foreshore is i not desirable at St. Clair, as a pleasure resort i "°i 13 desiriible. for other reasons that such ■ groyne should extend beyond Ihc depth I have ; mentioned. Any sinul working into the bight hrongu th« agency of t|,e grov-e would B ,'n 1° fhi l" 1 T?1 thMC ' S'-adually raisin., the level of the beach and enabling a roadway or e Sp ] Ma(le waU (o be constructed. , a bank of sand. Experimeu- . at groyne: Extended ooservation leads me to believe that 1:1 fine weather there is sufficient "flux ot sand into the bight pt St, Clair to , warrant the placing of a groyne immediately | west of l'orburv road, as preliminary to the consideration of othei proposed resiorjtive works. Such groyne could be made of cribs, triangular in section, and filled with the stones of the old wall now lying on the beach. I anticipate (hut a length of Moit from the foot ot tlie bank would lie long enough at first and • is estimated to cost 4100. The success of a ' gioyue at the place indicated would simplify the operat ons of the bocrd in dealing with the J'.splanade, and I would therefore urge that It be erected at- an early date, to get the advantage of the summer season, and that £100 be allocated for the purpose. Sen Ai alls.--It is always desirable to maintain a sand beach as the first and best defence rgamst the sea, fostering its renovation by every known means. But under conditions where such is impossible a bulwark or well of defence becomes an absolute necessity, whatever may be the consequence to the beach in iionl. the formation of a promenade or esplanade between the baths and Forbury road, essential to St. Clair as a watering place and i a likely boon to the community, is no doubt a work to be. included in any complete improve- I men! scheme. But the effect of the sea wall '• of such esplanade on the maintenance of St. ! Clair beach would, in my opinion, be injurious ' unless protected by groynes along its unshel- ! tered portions. Without such protection the j prevailing fetch of the sea, being more or less j deflected by the wall (depending on its desjgn), would in all likelihood operate in scouring the sand from the base or apron, rcsuiting in tjio lowering of the beach, and the possibility of under-mining and danger to the stability of tho wall, I am convinced from experience that the effect of a wall, inter alia, would be inimical to the conservation of the bench unless supplemented I by groynes, which would probably in turn I render void the utility of such wall by sanding | it '.in. My recommendation to the board would j therefore be that jetties or groynes (as already I indicated) for the restoration ot the beach be first constructed, and their effect' noted, before finally deciding upon the character and design nf the esplanade wall. Maintenance oi Beach and Sand Flats North of St. Clair.—ln order to prevent further waste of the Sandhills from seawards, it would be necessary to run out groynes from tho toe of ihc sand slope, as suggested in Messrs Miranis and Ussher's report (clause 16). and placed, say, 500 ft apart, so as to raise the beach and push out the high-water mark, preparatory to the erection of wind-brakes and fences for

fixing the sand and for the furtherance of plant growth. By the judicious extension of groyne construction along the outer beach, towards Lawyer's Head, the sand ridge could be induced to grow, and prevent the wash at high tide from lipping over into the lagoon. But as* the formation of such ridge might interfere with the supply of sea-borne drift for the reclamation of the lagoon depression, it might be belter left 09 it is', until the windbreaks and barriers hove done their work. Reclamation and Conservation.—Area: The acreage included within the space bounded by Victoria street, Fovbury road, low-water marl;, and an imaginary line drawn from p. point on the braeh to Onslow House opposite, is estimated by Messrs Mirams and Usshcr at 80 acres, and presumed to be the area intended in the Brat place to be conserved. I would suggest that the depression forming the extension of the la«oo'n eastwards bevond the above imaginary line, be included and added to the above area. For it is apparent that the raising and fixing of the surface westwards of such depression will tend to maintain it, possibly as a saltwater lagoon, a contingency which should be avoided by inducing its reclamation. Levels: The surface, levels sought to be attained bv the proposed works need not exceed the fineweather height of the bank at tho outer b:ach fronting the lagoon, in order to secure safety from inundation and render plant life pos-' sihle. The reclamation of the lagoon depression. and the growth of marram and other sand-binding grasses, will in all probability be accompanied by a raising ot the outer beach, while the surface generally may be expectrd to slowly but continually make! The fillingup of the depressions will n!?o tend to the increased displacement of salt by comparatively fresh water, and allow of the growth of trees and shrubs thai would not otherwise thrive. Buirinrs: I would recommend that durable I biirriare o> spaced palisading or slab fenc'ng b. l erected 'across the depressions, commencing, as alrendy suggested, at the extreme eastward cornel of the lagoon Iran and extending their ceclion westwards as the sand accumulates. Local experience alone will dictate the best directions and distances apart to place them. Wind-breaks

and Hedges: Alter the desired levels have been attained, (lie \viwl-brealts or hedges for sandfixing can be erector! and grass-sowing or planting commenced. These hedges need not be high, but must be close enough together to sheltei the young plants or grasses and prevent sanding up. Failure to clothe sand surfaces with grasses is generally due to v.niit of adequate shelter (or the plants while young, or b-fore they have had time to properly mot and spread. Scrub oi all kinds, beige cuttings. and thorns rati be utilised for these hedges. It in usually {onml necessary to .space th?m not wider than 12ft apart, to prevent sand movement while the seed is germinating, or the transplanted tufts gaining hold of the sand. Grass-planting, Ktc.: The growth of suitable vegetation after the sands are arrested, should present no difficulties v.-itli our abundant rainfall and generally mild coastal tcmpcnlure, provided discrimination in used in the selection of plants for different degrees of exposure and witness o( soil. In the historic fixing of the Lamlos of Bordeaux, referred to by Mr Hutcheson, Bremonticr divided the ':'.ic,i into

three zones. The first zone (facing the sea) was about ,1'i!) yards wide and phmt'-d with marram grass (Aruudo tireniiria), The second zone, of similar width, with brambles, heaths, all'.! creepers, and the inner zone, beyond the influence of si'-It water, with tile maritime nine iPinus pinaster). Marram fir.i=s: Of all ssndbinoing grasses, tniivam or Clonvbet (Amn'.'.o arenriyia) has proved the hardiest am! be.-t sand-binder in temperate climates, and ihe evidence of its suitability for our needs is liianir 'est in lis -nvrfsfi l l growth at Mus-'dhiugh. I would recommend this grass as the -taple sand binder. It is essential, however, to secure the proper kind, and in th : s connect'on thy letter- oi Mr 'Thomas V'augh, attached to Messrs Miiam's and [fr-shev's report, are of ini-iest. Mr Vaujli also d- srn'li:---. pr.ioliH methods of sowing and otaiitins; the »<c:l and roots. Tree-planting: .-\ftoi the mr.rram or other 'elected gras-cs have fixo'.l the .-and.-, the panting of picked shrub" and I lees could lis commenced ami extended seawards, as circumstance;-,, such '?.« the growth of sheltering ridges thrnui;h the binding inflnnc-'s of tlie gra«ses, permitted. It should lie clc.uiy understood that tree-planting should fo!':ow after the fixing of Ihe stirfaco by sand-bindivg grasses, and not before. The utilisation of otherwise waste land, increasing the a'.tr.'ctiveness of the Doman as r. pleasure resort, the provision of a sand-covering more permanent than grass, may be considered the principal object* of tree-planting. But is it absolutely

nrccssjiry to successful forestry that the pand be fixed, so that it may not choke and blast tho young trees. Sand drift in the neighbourhood of plantations must he prevented aic! avoided by the growth of yrafs. The simdi',"np of tho fringe of the bn'di or forest iiwr tha sen by the sand set (tee through ihp dest-ruetim of the grasses, is common ' tlircm-liout tho colonies and it is a familiar sight to ape i. f t , w dry tv.-igs on u sand dune, narking tho «:nvn oi some tree, green but n few months b°fore. Prohibited Areas: It is reconnr.ci:ded that the Sandhills and flats, with the exception o! tho outer beacii, he absolutely protected from traffic wherever sand-fixing and grass-pbnting operations are in progress. The Sandhills might be specially guarded by a .system .if barbed wire fener-i or entanglements, wtrch have proved leisewhere cfirient protection agaiin-t invasion, enabling the native s.ind Brasses to gain ground, as well as foster th« growth oi shrubs and trees planted thereon. Nurseries: In order that r. supply of plants may be available v.hen wanted, nnu their suitability to climate nnd situation tested, it is suggested that plots o[ ground in chosen si.iutions Ik laid off as nurseries. Standard vsnYties of sand-loving grasses and plants could there be propagated, and the adaptability of native grasses, heaths, shrubs, etc., av.'i o! various Australian and foreign plants tested, lleco'.nmendations.—ln order that the board may possess some general scheme, embodying the extent and scope of their probable operations, the following summary of recommendations is now submitted, together with notes on the future management of the domain, tha'may prove of value to the board. The proposed Works are arranged in the order of their priority. (1) Construction of experimental groyne opposite St. Clair. (For particulars "see addendum, page 10.) (2) Complete survey of Ocean Beach Domain and St. Clair, embracing current observations and collection of all ditta. necessary for locating groynes and walls, with cross sections at frequent intervals for future comparison and reference. (3) Construction of jetty groyne for the protection of the beach at St. Clair. (I) Construction of pontoon or rough limber crib groyne! for building up the beach opposite the Sandhills eastwards of St. Clair. (5) Kstnblishnient of nurseries for the propagation of sand-loving grasses and pla-nts, and for ■experiments as to the suitability of dif-erent plants for various aspects and degrees of saltness of soil. A list of various sandloving grasses and plants is appended. (0) Esplanade at St. Clair can be proceeded with when the effect of the proposed groyne in raising the beach has been noted, and the character. ritlier as a retaining wnll only, or as a, sea defence determined. (7) Sand barriers.— Erection ot harriers for reclamation of depressions, and wind-breaks and artificial hedges for temporary tiding of the sand preparatory to grass planting. (8) Management, of tho Domain.—ln the conduct of operations under the board's control it will be recognised that while their first attention must be directed to the prevention of further sea encroachments, their ultimate nim will no doubt be tho conversion of the domain into a people's park by methods analogous lo those described. TH.i success of such methods must depend largely upon the attention and judgment oi the board's emn\ove?s, as much ot the work 0. conservation will he on empirical lines, and iletai.s of procedure dictated by the experience, gained as the work proceeds. Curator-I would suggest, therefore, that the direction of siilid-hxing and tree-planting operations ho placed in the hands of a gentleman eminent in botanical science, etc.. who would be willin" to act as curator, and lo whom the manager or local officer of the hoard could look to for guidance 111 the above important part of his duties. Manager.—lt is also suggested a manager be appointed, possessing a knowledgo ot landscape gardening and forestry, mid powers of initiation and observation." The duties of such an officer could include the charge of the domain nurseries, supervision of sang-fi:;,ng and grass-planting, and acting as Tftnyei' and prosecuting officer in the enforce"lent of tho by-laws, rules, and regulations necessary lor the maintenance and protection ot the board s property. Expenditure.—As the board might desire to possess some idea of the. probable expenditure required in performing the functions of maintenance and conservation on the lines herein suggested, I have endeavoured to approximate .he cost of continuous operations and management, as well as the cost of non-recurrin" works, over a period of live years from the initiation of such works. The annual cost for management and labour extending over the above period, including manager, honorarium to curator, officc expenses, labour, maintenance contingencies, is estimated to be for the first year £COO, second year £600, third year XGIO fourth year £735. fifth year £750; grand totai lor live years, The total estimated annual expenditure for the period of five years including surveys, jetty groyne at- St. Clair groynes onpositc Sandhills, esplanade at St! Clair, sand barriers, wire fences and entanglements, nurseries, seeds and plants, management and labour, is for the first- vear fISOO serond year £3000, third year .€1230, fourth.vear *1435, fifth year £900. Total non-recurring expenditure, .£5100; management and labour, per statement, £3325; total expenditure for five years, i'BlG5; extra for wnll of esplanade, constructed in cement concrete (as sea defence), £1500; extra lor wall in timber, £3l0;-grand total, .£87:15. List of Sand-loving Plants and Grasses.—For sea frontage: Marram grass or gourbet (Arundo arcnaria), sea lynie (Klynms arenarius), sen wheat (Triticum junceum), Celifomian giant or land lupin, Australian coast titri (Leptospermnn lanigeriimn), branch - spreading plagianlhus (Plagiantlms divaricatus). For mner area: Manuka scrub (Leptospermtm scopariuni), Tasinaiiian titri (Leptosiiermim laevigaUini), NewZealand bramble (Rnbus auslralis), sheoak (Cr.suarina poiidula), slieoal; (Ca?uarina siihcrosa), wattles (such as acacia daalbata, mcla.n, and mucrciiata), maritime pine (Pinus pinaster), sand-loving eucalypti, sand-loving heaths and creepers.

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Otago Daily Times, Issue 12219, 6 December 1901, Page 2

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6,593

THE PROTECTION OF THE OCEAN BEACH. Otago Daily Times, Issue 12219, 6 December 1901, Page 2

THE PROTECTION OF THE OCEAN BEACH. Otago Daily Times, Issue 12219, 6 December 1901, Page 2