The Salinity Control and Drainage Inquiry - State of Victoria - Submission of Keyline Irrigation

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pARLIAMENT'ARY PURLfC

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'IHE SALTNITY

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ANti'l;iriJ-l*i:tll::; ii.r01.iiRY

SUBMISSTOI{ OT KEYI,,i.H.I] IF.RIGATTON

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YEOI\,IANIS

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Sponsored by

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THE MURRAY VA],I,EY DEVEI,OPI"IENT

LEAGI.]E

PARLIAMENTARY

PURI,IC WOR}{S COMMITTEE.

(V]CTORIIi) THE SATIN ITY CON'lllt(-il, 1:\ijii lliil\l i.ll\(li1: INQUTRY

Submissiorr by G " V.

LAW11UNCE

Executive DirecLor MURRAY VAI,LEY DEVtil l-ir[rl''tr

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Prepared for Irearing aI Melbourne on June 1 L911

l:-e Murray Valley Development [,t-:.itJili': !t"ls ,aocr;;ted Mr - P. A :'eonans "Keylinet' principles d:j J{r[-I](,)f)I-t.rt-t,r and valuable :cr the development of Iand-anii-u;ater usc practices in the I'i -rrray Valley.

I have been ass(rc i atcrl wi t-h t'Ir . Yeomans f or: scirre twentyf ive years ancf have qradr-r;l 111r come to the conclusion that his concepts r orr ig irial 1y accepted f or a :estricted function in relatively higlr rainfall undulating :ountry, have a more universal application. "

lour Committee has to consider .i $40 rli l l ion scherne for the abatement of salinity in the Ivlr.tl taf ilir:t"t ' I lrope it will :.ct balk at recomlnendirrg, say, :i40 t-i'toIis;,tttt1 t-o explore Lhe :-ossibility, I say hicrh probabil i Ly, o1' Keyline prescriptions reading off much of this expenLlibure or conrpleting it. :ir. Yeomans evidence will travtii'se thc hist-ory of the failure ''.;or Id wide of perennial f loocl i t.r ir;-it, i tlt't , exartnine the underIyrng causes ana aff irnr that 1(t:','iit'rtr i.rt'ittciples, applied at *.he comrnencement of irr icla1i6n :i(i il(rllr(':'i lv i l 1 t-'nsure their r)ermanence.

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lle is more caulious abo'ut curitr'1 thte iil:; r.r1'' t-he llreserrt large governnient sctlclli(r.c }-rtlt srl'l (,cst s t 1i'r l ,r Pr'()(-' r-c.ss iv, rorking through t ltt i r- ; i ';;r t' i rln il rcils rjoi'i 1 I r;radrrally moderate their s;llittii '' ;ttt<.l t-ir'ir"l u'rl' I - .r i, i 'r t:t-lr,'r-'t-s 1

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i{hen it comes to r}e\d llro j ecLs Mr " Ycotnans LJi)L:s L nLo considerable detail on how lancl s;tiould l-rt' prcpared ancl l'ror+ danrs, irrigation channels and steering Lranks should be sit-ed a great ana iormedl ni" proposals clainr that there wi"ll be given a reduction in the amount of water used to irrigate

area (it will be applied ten times as fast as in current practice), a great saving of labour costs and no increase in. salinity. the tilurray Valley Development League through its consultancy (which it owns but names for me as "G'V' Lawrence facitity anil Associates") has laid out and is supervising a project for Keyline Flooci-flow irrigation in New South Wales on the Snan nif f (Vic.) to Moulamein (usw1 road' The Corimittee is invited to examine the project itr its prcsent formative stage and to take a continuing inLerest in its performance" The Cornmittee will also bre asked to arrange for a demonstration in Victoria to be carriecl out by this League through G.V. Lawrence and Associates and designed by Mr' Yeomans' I:. 1.'ancouver in M.ry-June L97 6, l - Ye{;rti';tls littd l attenclcel :.-.e Habitat Forutii *lli"t, ran parcl 1]el v;i t-1r irAilI'I!AT, Lhe , and -:. ite,d Nations Conf erence on tlulllarl Set t l enlt''lllts Plan f or ine :rstributed the booklet, I'he Austr.rl-lan Keyi FIan) , (Austr:al" Keyline ian ::.e Enrichment of tluman Settlemr:ntand gr:eat interest rt' createrl ;:ich f tender as an exhibitto the messages tvTo :.any contacts were niade. The I'oruni sent more therefore :fflcial delegates. rn the secotrd, and ccnsidered message, were the followinc; words adopted on my :.::ion: "Land musl be managecJ c.-rr-ef u11f in order: to maximise --i.e water resources f rom which distri L'uting systems derive ::.=ir supplies, T'he productivi: non-'i>c;11u1-inq use of waste ;e'-ers ancl the Lr:ansfornation tll sul'-si,i I into productlve :ertile soil i-s a fi-rn<l;rmerrtal ll(rrresstLy"' I'1

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i believe that ther acloption o1 l(eyIirre 1;t'ii:ciples and :ractive can achieve in Australi;r ;rrrd .:l scwhere the cijectives stated in Lhe cluoteci vror:ds" 'I'ht: Murray Va1ley )evelopment League has writteri t,o tl-ie healls of all 120 nat ionll clelegat ions to HABf TA'l' , ntak i ri11 SUrc) t-hat the iustralian Keylini: P1;rn reaci-tt'ri tltt.:ttt .rnr.l sayinq that G'V' :awrence aucl lssoc i.tLr:s al^c [)l t l,,l-t'I I ^:i'lvisc arnd supLj|visc anylhere.

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l ian Plan f or the Enrichment. 0f }iuman

urgent, detailed consideration

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It provides correct designs fcsr specif ic landscapes It controls, uses, purifies, avaiiable water"

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and re-uses all

It transforlns suirsoii intc; soil.,

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Dermanent enrichnrent of l-anri ciriri ,,riv

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It provides econorrical struct-urL. i:larrs on which planning, arch-itectural an<-l ot-her sk j 11s and the provision of roads, power ;ind ret icu lat-ed water: can best be applied or suppr) ied l-;1, their respective expert practitiorrers

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It lends itself both to priniitivci and t-o sophisticated implements ancl methods. Peoples with poor financial resources could do the work themselves with minimurn outside aid.

Housing could be simple to begin wiLh but within thiS basic framework could be progressively upgraded to any heic;l-rt.s of

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',r--er is the one L-l eiii{-,rrt. which can be nianil>ulated, -: Jontrast to landsir;r1;r,.:, a ir ;rrrcl cl irn.rte , wh ich _-..rruL.

"The PIan controls or utilises iri111, al l Lhe rvater --nat fa1ls on or is brought int-r; tl-re sit"e.

"The PIan recognises in stormw.rl er run of f .ind sev,'erage ef f luents, massive quanl it i es o t '.'aluable fertility elements wi-rit:lr it p;rrts t-o ::oduct ive use and el itriinates Lirr,:ni i.l s ii :i()uI-cc

:: lvater borne pollution.

"lrrj-th regard to air, whilst tl're .rntbictrt ;rir nrtrst, De accepted as it is, the Plan tlcpenc'l :; ilL)()n aerated deep soi.l . T'he forest rowLl; r",iric:h is l-ntreqral with the PI;rn wil l irrcL'east,: t lit. o-:ivqcn content of the a ir anri llsâ&#x201A;Źr thc c;tri,roii ,1ii;: itit.r. " c-1

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Lacer, and again with members of the Committee, f inspected the Campaspe Catchment including visits to individual farms, not in heavy rain but the wind and the col-d. were quite remarkable " : -::ally in Melbourne the Commitlee afford.ed me the :::crtunity of presenting Keyline principles and practices ::.a'. were relevant to the inquiry"

::t:s was the first and only serious official_ examination :=- -*he Keyline P1an. f was grateful tc, the Committee for ::=rr attention and consideration. Also f was impressed -,.'-*-:r the great National value of the parliamentary public ,,:::<s CommitLee system" It was good tCI learn that, through --:i-s system, parliamentary decisions on substantial matters -:= made after all concerned, experts and laymen, have been :-le to make their submissions" l:-= oonclusion of the inquiry gave me a measure of satis* :::--ion since an implement and a technique of Keyline :-:-.'ed a significant role in stabilisinq Lhe Campaspe -:--\man*.

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i1.' presentations to your CommitLee will again be proposing ::inciples and practices that are ernbodied in a total ::::cept that concerns almost every association of people ,.;j--;h land and water that I originated and named Keyline a l::.rter of a century ago.

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on this occasion there is a difference:

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earlier submission was made personally rvhereas no\{ f appear as an Honourary Life Member of the Murray Valley Development League with the sponsorship of the League.

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THE TRIUMPH AI{D THE TIitr\GCi-]Y OF TRRIGATION

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.:.e need for Lhis inguj_r1, suggests that the problems of : =:ennial flood irrigation are now fuIIy recognised to '= cf very serious national consequence * probtems which ",;::e unforseen or ignored in Australia when our large s:ale public irrigation developments were initiated.

But --:.e encroachment of excess salt wher:e the::e was l_ittle or :--:.e evident before irrigation and the problems of drainage --::=t ',.iâ&#x201A;Źre non-existent until they were cr:eated by irrigation ::e by no means unique to this country: they are of world* ',.':e significance and have been for many cenLuries past" -:.= nistory of perennial irrigat.ion in the older countries ::scloses a long-term consistent pattern of great success := the desert bl_oorned, that was followed., after a varying :--':::5er of years of declining product_i_on, by disaster" The :'::al disaster was the abandonment of salt encrusted or -=',,.-arped-out saline land and. the tr:agedy of the people :::ced from their homes in the irriEation communities" l.::ab1e examples are lands of both the African and :*rorean shores of Lhe Mediterranean Sea where irrigation iarning as well as the cropping of grain without irrigation, -ea to widespread soil destruction and 1and abandonment.

I:: this century irrigation developments in Northern ?axrstan were abandoned as the land became white with salt ::crustat-ion, and as recently as trvo years ago near raEhdad, Iraqi irrigation farmers spoke to me of irrigating --ieir land and of moving on to 'new' land after only tz -,'ears or so. Their 'new, Iand had f irst been irrigated ard abandoned centuries earlier.

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of the abandoned irrigation land underwent this process of natural recovery and eventually became irri-gation land again when the pattern of success followed by later abandonment often repeated itself.

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THE LONG STANDING DILEMMA OI' IRRIGATION

:-' is submitted, {1) L.hat it is this ancient dilemma of -:nd destruction by perennial. flood irrigation thal has ::J',.,' overtaken our: modern and relatively new trrigation :=velopments i Q) that despite improvements in =::ineering desigrs, equipment, construction and drainage ::.erhods which have extended the life of some of the ::rigation 1ands, the critical factors of ancient and ::esent day irrigation remain substantialLlz the same; (3) that the real problems of irrigation =::d are not salinity and drainage but are much more deeply seated in a system of irrigation that is ecologically :::sound and of which the problems mentioned are clearly cily the symptoms"

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I:: support of this diagnosis the attention of this lcnmittee is drawn to the following natural facts: On =gricultural lands that are endowed with adequate to =bundant rainfall of 25 inches to 40 inches (625 to 1000 :.jr) or more there are none of the perplexing troubles of cerennial irrigation districts; there are no serious drainage problems and salt encroachment cannot exist excessive salting occurs in Nature only in very low rainwater to wash ia11 conditions where there is insufficient out the accumulation of salt by evaporation, salt that is present in very small quanLitir:s in the purest of waters

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-..a. repienish the 1anri" 'v'lhy t-herr on ar:eas of sparse or ,:--::lequate natural- rainfall is tire addition of irrigation /.-r --er, that raises Lhe 'rainf all-equivalent' to the ::equate or the abundant state, invariably followed by --:re problems of water and land that are the subject of --::1s inquiry?

--- -,.,'ould seem these probtrems are completely unnatural and ::-.i there must be something basically wrongrl ,'as not old world irrigation an immitation of the annual :-::Cs which have inundated the flood plains of many rivers :- r-he world for centuries and, except in cold regions, had r --,';=vs

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:j.= following crop from this one controlled inundation? .:rs 'basint syst.em of irrigation with j-ts very frugal use :: .,.;ater had a substantial degree of permanence since it s 'ccessf u1ly persisted for centilries "

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promoted tremendous growth? Had not the same results ::::red when the first irrigators sor.tght to control- the ;=:er of the annual floods and succeeded in spreading the .,"'-a--er far beyond the natural flood plain where a limited :-artity was allowed to soak j-nto the land-and to produce

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-::= real problems of irrigation appear to have arisen when :.:n-made 'f loodings' were produced every ten days or so -:: rveeks or months on end for many years. It seems that -,.':.3t r..,,as greatly beneficial for the soil and for plant ;:rci,r'th once each year, led to the eventual destruction of --a3 land when it was flooded so often in perennial irrigation.

Ilere tras 1ittle question that the land needed the additional -,.,'ater; ther:ef ore the def ect in the system of perennial irrigation was ei-ther:

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in the way the water wasi ;rppiiect tc the land in the amount of water that was forced into the landr or 3. the land selecte<1 was unsuitable for irrigation.

-:-3 in the older countries there are areas of irrigation land - :, ".his state where poor natural drainage such as on o1d -...'=: lands and/or sal-t content should have excluded -::igation.

::-=re may be justificat.ion for con.,rerting salted areas -:--,o productive land where land is in short supply and -::sh rvater or rainfall is plentiful as with the great :-::ers of Holland that have transformed the shallow sea ::: into valuable farm 1and. Horrrever in Australia where -a::i is plentiful and both fresh water and rainfall are in s::::t supply, the conversion of saline land into irrigation ::eas by the use of elaborate and expensive drainage works -s jir\r,d.rrd.rrted" This is particularly so where. totally '*::-ike the situation of the Dutch polders, the sal j-ne water :."s: return to a distant sea via a river that is needed for --:e supply of fresh water to its r:wn vast landscape")

-::e Purpose of this Submission is 'L.a put before this l:::::rittee of Inquiry two propositions, to elahrorate on --:-en, to present arguments in their support to show that ::re problems of irrigation land can be readily resolved :::i to sugg:est how this can be proven.

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?:cposition [l--

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that, excluding {3i above where it applies, the problems of perennial flood irr igation of the past and present, namely salinity, rising '",rater tables and drainage problems, including the at,tendar.rt declining soil prodr-ictirze capacity, increasing diseases of crops and animals, gireat waste of water, increasing depenrtence on artificia1 fertiljsers

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ancl fiiral lanci abandonirtent, are caused in large measure by the methocl or the manner by r,vhich the water is a pplied to the 1and. and t.hat since current methods of applying

the water are sancLioned by the engineering designs and layouts for distributing tlre water in t.he irrigation Cistricts, it f ollows that the whole system of both past and present perennial flood irrigation cou1d. be sericusly at fau1t"

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of perennial flood irrigation land that has rarely been known before; and that these new concepts and methods will reverse the process of land deterioration on the areas already damaged and will recover the land to a condition more fertile and productive than when it was first brought under perennial irrigation; whereuponr with the continuance of these methotls, the land will be permanently productive.

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permanence

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that changecl methods of irrigation design and water application, associated with new conce s of soil care and mana ement, wil1 not only avoid the problems in the future but will rapidly improve the depth and the fertility of the soil of irrigated land, increase the prod.uctive effectiveness of the water several fold and sulport a degree of

Pr:oposition

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the manner of applying water to the land.

Old world perennial irrigation systems that eventually caused the abandonment of land appear to have employed even smaller irriclation streams than those jn use today, rshere vrater is applied to the prepared land at a rate of f lorv that j.s limited to 5 cusecs (112 500 gallons, 510 000

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of thre s;llt-s content ofi thr: i,v.rt,i:r. ilhe neecl Lo provicle the lower parts of the irrigat,ion bays with their quota of water ensures that the upper areas absorb more than the soil can use effectively and water often flows frorn the bays during the over-long in-soak period" A substantial percentage of the water is thus wasted and proctressively added to ground water: to raise the rvater tables and eventually to bring to the surface ancj.ent deep seated salt to further foster salinity and drainage problems" cr-.:,i:i.:i:::lri:rai_ion

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A major requirement for the increased. :::iuction of plant life from irrigated land j.s ttrat the .-.:-1 must use greatly increased quantities of air whereas --:-'s irrigation procedure itself soon restricts adequate air -*:, progressively shallower horizons in the soiln and the '==:er soil dies

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::: instance; it has been observed that land with a natural Itr",-er: of soil seven inches deep has, after only ten years : : oorder-check irrigation, as f.ittle as two j-nches of =:--i:;e soil- remai-ning. The missing five inches of soi1 -'.'1s not lost be being washed away in soil erosion; it is s:iiI in place but has been transformed into re1-atively -::el:t subsoil orving to the restricted penetration of air.

-::= nutrients in the lost soil are no longer avail_able to :-..nt life and the thin top-soiI remaining is burdened by :'.-.:r increasing amounts of artificj-aI fertilisers and other a:-ro-chemicals in efforts to maintain profitable production. ?:oposition

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changes in the application

of water to the land"

ra the excessive length of time that rvater is in ftooding ccntact rvitli the soil is in fact a founilation proLrlem of rerennial irrigation lancl, then the opposite concept of ' br ief f loodi r-rg cont-,;rc L of rvatcr lvith the soil r shoulcl be consider:ecl as t,he .lns\./er t-hat. m.ry avoicl t}-re problcms.

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,, t.iL)]!{tellL. Of f }ir.- 1.;f f.e:{ 'l''1.O,;, i I |,-t ,,: r-rf ti.i.i(-1 1-. L,l i f-'l iqa.t j,r-rn '.-.i -,:ir r lvith tlie soi-l or j-ginatcci a.r:i thr=: Keyli,rrr: Flan F,.1 rL t;f ',::-rrci-i proposed that if agricultu-r.i-L l-and vias to remain :=.nanently productive, the processes of production from iar:riing and grazing land must become also procedures for .

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--:ansforming indifferent soil and inert subsoil into deep :=:tile soil. The subsoil including the near surface :,:onposed rocks - which i.s many times thj-cker: than the .:,- I itself, ifas seen as the larqest and most valuable -.=;csit of mineral and chemical- wealth on Eartlr because s: :,:ch of the subsoil can be tr;rnsfor:med rani.dly j-ntc> .^==:, fertile and productive soil "

-::= techniques for this transformatio.rr of poor soil and s:rscil into fertile soil- were suecessfully developed =:c;n experiments started in 1943 and recordeC later in line books: /The KegTine PLan' L954; 'The ChalTenge of Landscapel -)5:: 'Flater for Everg Farm' 7966-68; 'The Citg Forestt l-97L and .The .l'.s::a-Z:.an KegTine PTan for the Enrichment of Human Sett-Zements' 1976 _::ese-rted with the sponsorship of the I'Iurrag VaTJeg Development -;=::re at the Habi"tat Forum of the United Nations Conference on Human :.='..

-'=::-Ze,ments, Vancouver 3 Canada)

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-::= first three books are out of print. at the moment; copies a:c available at libraries. Copj-es of the Iast trvo are s-.::rtted to this Committee of fnquiry" *

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Planning Objectives of Keyline (to be discussed later ) ::e the complete control and maximum beneficial use of al1 arzailable vrater. Every othe:: aspect of planning includt:t ::oads, subdivisions, f encinq, builciings, r^,,here trees ---Y Ieft or planted, and areas for soi l improvement are lccated in compatibrle relat.i-ons1-rip lvith the lines ancl the structures that are necessary ta achicve these rvater ol:jcctives.

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ir7,i-riai l',t:y i -i-rri.r f a::ms thr,: af farm dams that wc.re sr:meivhaj: large:: th;:n :::struction .s,-1a1, to store all run-off water" Tire dams rvere equipped ,..-'r--h outlets through the base of" the earth wal1s as the most icEical means of using the stored water for irrigating the described -:.nd. Irrigation proceeded on what agri.culturalists as ",^rorthless shale ridges' , and was apparently ef fective but =::evzhat s1ow. o,-t

It r*as obyious j-mmediately that greater flows could

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dams, reconstructed with much larger outlets and ::e-,r dams provided with the lockpipe system*, multiplied the :r;Eina1 flow rates by upwards of tenfold" These larger : lc".'s of water displayed a work-force, absent f rom the smaller ilows, which overcame land surface irregularities and :roduced a completely even spreading of the rvater. With -*:le soil cultural practices already j-n operation, there was achj-eved a uniform and readily controllable penetration of i;a-1--er into the earth of the ridges and valleys of the ;:-Culating

land.

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be7ow, the Lockpipe Sgsfem.

greater: the flow of the irrigation stream t.hat was used better the result became in water and labour economy" flows -::is watering of undulating land employed irrigation --..:-- lv-ere several times greater than Lhe maximum rates of : - :-.': empl-oyed in irrigation There were Iimits districts.

--l :he flow rate of the irrigation stream that were .imposed ^.'- the short lengths of the slopes of the ridges; however, ',,':r3n it came to irrigating the fl-atter lands rvith their longr, :=ntle and more uniform slopes, the rates of f low \^/ere again t :creased.

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In mosb situations the grcat,ly superior flo'"v rate can be acirieved economically onJ-y by'sLr:ck-nitring' ttre a.vailable :,.'acer in specially construct"ed farm dams and by releasi-ng -,he wat.er through a 25 inch (610 mm) or larger Lockpipe sirstem placed belorv the wa}1 during construction.

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fcr irrigating, tLre water is released through the large -,-alve into an irrigation channel constructed contour-wise acj:oss the 1and. From the irrigation channel rsteering :-:nks' that form the long and large irrigation bays of 10 =::es (4 hectares) more or l-ess, .are constructed about two :::: a half chains (50 metres) apart, i.n a right-angular jashion from the irrigation channel dou.n the maximum falI :i the land" -::= f ollowing paragraphs, marked with a vertical line gj-ve --e:hnical details of Steering Banks, Irrigation Channels =::e l{ater Gates and their operation.

.::: settled height of the steering banks is about seven or =-:rt. inches (200 mm) and thej-r lengths may vary on different ;:rjects frorn one quarter to Lhree quarters of a mile (400 to - ,2a 0 metres)

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-::: special function of the steering banks is to hold the -,..'a.er against spreading widely and dissipating its work =c:ce. The location of each steering bank follows the ::ecise path that a stream of water would folIow unaided :i the stream could be made large enough. But a flow of :::e million or even trvo million gallons an hour (nine -,il]-ion litres) on 1and of only slight slope would soon scread widely, lose its positive forward rnovement and iinger-out into numerous small trickles florving anywhere according to the slightest variat,j_ons of the surface of the land. On the other hand on lancl of onl1, one in 11000 or

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or no sloi:: a"t, ai1, rii.: p_.;riL.j-ci:la:.]ccations of the steering banks plus the fact- t-h,at t-he surface 1evel of the water irr the irrj-gation channel is always one foot (300 mm) or more higher than the irrigation Iand, imparts a fa1l from the surface of the water in the channel all the way to the distant end of the irrigation b.y. The work force reposing in the sheer: volume of the large flow maintains a positive and uniform forward movement of the water to the end of the bay.

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Io release the water into the irrigation bays the lower l:ank ci the irrigation channel is equipped with water gates :sual).y six feet wide and two feet highr so that one orr on large projects, two gates open into each of the bays formed D)/ the steering banks " The l_ower ends of the bays are open. .ne Irrigation ghannel is very different from the presently '-:nployed farm ditch of irrigatlon districts since it carries :en to twenty times more water" fts cross dection is :elatively wide and flat.

The earth for each of its two :a;rks may be obtaj-ned from inside or outside the channel =:ea according to circumstances by sidecasting with a :, -: l- l-doz er " As well as outlet water gates in the lower bank ::e upper bank is equipped with inlets or fuses automatic - lt cperation in order to permit upland run-off from rain_

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on pasturer or mixed cropping and pasture enterprisesr the flow efficiency of the channel is maintained by making the feed it produces attractive for stock to eat down hard. In the absence of stock the channel bottom is kept in order by

morving.

the lrrigation channel is on land of more positive s lope such as one i-n 50, a single bank channel is employed.

l',here

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i-ornL the -l ,,r,!i ,tly :-:..1 i:-i() r-iiii.er: :r)lrtCiably from the banks of bor:rLe.r"'-r:heck, both i.n the ::.:nner of their location and in the methc;ds of construction" ..--r-

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l-t:f:f inc; Banks th.rt

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::irst.Iy, they are.located on the precise line of the maximum al-beit very gentle falI by a series of pegs which are then icrr,alised into straights of which there may be only one, or --;',c or three: The Istraights' are then suitable for sub::..'ision fences, where needed, to be located along the banks" S=conc1ly, the formatised line of each bank position is cultiv* =--=,i seven feet (2.2 met-res) or more wide with one or two runs :j'a farm tractor and chisel plow or S1ipper lmp*" Then the :.:;l tractor and a rear mounted ditcher blade sidecasts from =::h side some of the loose cultivated earth to the line of The height -rr=gs placed in the centre of t"tre cultivated strip:1 r-he unsettled bank should be about L2 inches (300 mm). l;:ir ly, this procedure leaves on each side of the new s--eering bank a small channel which has to be 'stopped! with =a:-.h every 20 feet (6 metres) to 40 feet (12 metres) in ::ier to prevent irrigation water from flowihg down the sma1I :::=nnel. The earth-stops may be placed by hand shovel or by x The SJipper Imp is a cuLtivating -a:n tractor and di.tcher:-':-:ire of recent development. rt js described jn a manuaf that is .'.'.:labLe ta the Committee" 3eneral1y these three steps are all that is required in land ::epa-ration, the 1ow cost of which will be apparent. ation Starts rvith all water gates in the irriqation channel.closed. The Lockpipe valve on the dam is then cpened and water flows into the irrigation channel" The water gate (s) into the first bay may novr be opened but a little delay is preferable since an accumulation of water in the channel irnproves the rate of flow into the first of the bays .o be irr:igated and maintains a faster and more uniform rate of irrigation throughout. rrl:I

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-

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ii.- ,.vat-er gate into thr: b.ry i;eirlE ir"r'-rcliti:'C is r.,;,losr:cl before the water reaches tire dorvn-:;l-i:earrr open encl of L.he bay so that the water then r:emaining in the bay is just sufficient to complete the bay vrithouL run-off from the bay" j'tLen the water in the first bay has reached this prei=termined position the water gates into the second bay are ::ened and those to the first bay are closed" The gates to --I:e next bay to be irrigated are opened just befor:e closing --jicse to the operating bay. l'

-1is procedure conLinues to the second last- bay when .L.he ::erator needs to close the Lockpipe valve at the dam when --::ere is sufficient water in the irrigation channel to drain:':t and to complete the irrigation of the final bay.

l;le water gates to all bays may be opened following the :cr.pletion of irrigation, in order to spread evenly the -,.''ater of heavy rainf all when it occurs " Alternatively rain ::::-off waters may be prevented from entering some bays and ,--.':assed into others.

S:eciaI Soil Cultural Practi-ces Are an Essential part of :ieyline frrigation procedures" During irrigation the water is in flooding contact with the land for short periods ontr-y; twenty minutes is the desirable maximum for the largest and longest ef bays. ",nile a'deep and highly fertile soil may be able to accept ics fuII quota of water as fast as it can be applied, a cornpacted or poor c1aye1, soil may take some hours to absorb only two inches (50 mm) . Therefor:e sr:ch soil is cultivated immediately prior to irrigation so that -Lt wiII take in rvater as quickly as the most fer:tile of scils -.1 matter of a 4

l-7.

c or two. Once: er i t,he,r, s,-.:.r- i the f c-rr. t i-le sc-i.i. I ol: the :onpact-ed soil that ha-s; been prr:ope::Iy aerated by cultirzation - has absorbed its quota of water quickly, the j-nsoak of iurther water into the earth slows down very markedly it almosL stops. Since the time of contact of water and soil is so brief, the different-ial between the amount of water absorbed by the upper and the lovrer parts of the bays is -.rinut.

l_

::,lnimaI

I

"

-ee Type of Cult.iyation 31so f s of Signi-f icance-; there should. : 3 no unavoidable mixing of surface and subsoils " The ideal is a cultivat'ion which aerates the soil and some of the s:bsoi1 below but otherwise leaves the cultivated mass in place"

ln poor soil the depth of cultiyation is gauged to allow only --he desired guanti-ty of water to enter the soil.

For instance a certain shallolv pasture soil only Lwo inches deep may be ::I-uivated to a d.epth of five inches inclu{ing three inches into the subsoil when the brief contact time of water with --:re soil will permit only two inches of water to penetrate.

Iae Soil Making Procedures" A poor compact.ed soil and subsoil - which has been aerated by the appropriate cult-

ivation inmediately prior to the first application of irrigation water rvill generally recompact after graz,ing or narvesting to a degree that will require further aeration in order for the land to again take-in rapidly its proper quota of water during subsequent irrigations" This Cultivation for Aerating The SoiI Is the Mechanical Part of the Kelrlir-,. SoiI l,lakin Procedure. The general response on pastur:e land to this first cultivation and irrigation dr.rring v/arm or hot weatl-rer is spectacular growth accomp;rnied by a cJuit-e as notable increase in the growth ancl mass of the root s1,.stems of the g]:asses and legumes which penetr:ate rapidly ii-it_c_r the noist_ aerrat_cd earth.

I

18.

i,'iilIr t.he p:rsture is given its't.-ir.r.(: !r.r i-jji,lr../' r.rridist-urbr:d by sl,:or:k, the root systeros will r'each l-he rurl1. depi"h of the aeraLed earth soi1 and subsr:il l:y the Lime the grasses approach the flowering stage which may be 16 days or less in warm weather and longer: in cool conditions.

The pasture is then mown or eaten off t1i:ickly by stock.

3rass-Shock results from this drastic interru ption of the :astures' normal urges and growth ceases imn,.ediat.ely. fn a day or so the pasture recovers from grass-shock by using -rp the nutrients that were stored in its deep roots ready ior the reproductive event of flovzerinE and setting seed" lnese deeper roots then die off and shortl-y ther:eafter new :oots start to grovr downwards: They too will reach the fu1I depth of the moist, aerated earth if the pasture is again l-eft to grow without disturbance from stock or mowing"

J:rder this type of management, each time the grass becomes :,;e11 grown it is prevented from florvering and reproducing seed, when it responds by growing greatly increased masses cl roots " When newly dead this mass of roots is probably --he best food of all for the micro-organisms and for the iarger species that make up the l_ife*in-the-soi1" Each crop of roots as they die provide the food for successive cl-imaxes in the soit as soil-Iife of population explosj-ons "

proli-ferates in

sequ.ences

By progressively deepening the cultivation say three times in the warm weather of the first year only - a succession of rising climaxes, each fed on j-ncreased. masses of dead rootsr are produced in the moist, warm, aeratecl earth. Subsoil is thus rapidly transformecl into deep humus laden fertile soit"

l9

"

1'his Creation of Soil has been found most rapid on mixed ,-ir.irss and }equme pasti-rre land tLrat (lar] k-r.' ir:::icJaterl quickly at wi1l" A gr:eater depth can be t-ransf-.ormecl under- these conditions in one year only t.han can be br:ought about in three years under 25 inches to 30 inches {625 to 750 mm) cf natural rainfall conditions. l:ie formation of soil is not necessarily the exceedingly s lorv process that academic and professional agriculture ras taught: Quite the opposite; its d.evelopment under ::lese conditions of warmttr, with adequate water and air :rovided, is related in time to the very brief life-cycles ci exceedingly small organisms" It is very rapid indeed" *

*

*

As indicated earlier Keyline irrigation was developed originally on a class of land that was neve.r irrigated before, for the use of water stored in farm dams that were equipped wi.th a Lockpipe system for the grav.ity release of the water. Therefore the size of the irrigation stream could be freely based on practical considerations of manpo\^/er and water economy and not. imposed in any way by outside influences such as by the limited irrigation streams delivered to the farmers in public irrigation areas " I{hen the large flows were first proposed and used many years ,go, irr:igation officers and soii- conservation staff were unimpressed. Government l_oan monies that tvere normally available for farm dams and irrigation, were ur1* availal:rle for farmers projects if Keyline methods were proposed. Such ::ejection seemed to be based on three criticisms, namely (1) that 1,ire tr:ansf ormation of subsoil into deep fert.ile soil quickly enough tc be of benefil to the pr:escnt generations of farmers was phl-sica111, .lrnpossible,

20.

(2) t-hat- hhe non*us.l or rcdrici-.i or; r-ri ,;:r'1- j i.i!..r.i,l 1 f,cr:til.isers and 'pr:ot.ective' chernic"rl5 yri)s impr:aci-icaJ sinr:e more of them were needed to maintai.n yiel-ds anrl (3) that rast irrigati-on would not aIlow sufficient time for the water to soak into the land and it would run off and be wasted.

There were other worries a1so " A response f ::om one of f icial i';ith 30 years experience irr farm r^:;rter Cerzelopments, to the million gallon an hour irrigation str:eam ''he'11 drown himself or rvash the bloody country away' was typical of qualified cninion then, and without the experience of having irrigated withr or even having seen such an unprecedented irrigation

stream, the reaction is nor:ma1 enough.

irrigation officials are a l-itt1e more inclined to commend the large irrigation streams of Keyline they are much less inclj-ned to consider the necessary soil cultural techniques thaL make it so" E',.ren now

when

A recent undated publication styled "Flood Irrigation Systems.

I'iodern Techniques and New Development in trrrigation Practice" is a case in point" This document, a copy of whi.ch is tend.ered in evidence, appears authoritative since jts co-authors are

officers of the Victorian Department of Agriculture, borrows without acknowledgements the Keyline cr-iteria of fast flood flow irrigation for stock-piling the irrigati-on \.,rater in farm dams with large pipe outlets; for: the large and long irrigation bays and for irrigating at the rate of "10 hectares (25 acres) per hour or more if desired". Horvever it makes no mention of the essential soil procedures but leaves it to the reader to assume that the land will absorb the water rapidly without prior aeration. Then tl-re paper appears to reverse the rvhole concept by aclvising that it is quite practical to use the "extensive layoul-" of tl're large and Iong bays without providinq an ir:rigat-ion dam; that "bays 40 metres wide and 800 metres long ol: loncler: can be irrigated direct from the metered out1e1-s" ;,rrrcl "t\"/o sucl'r bays could be

21

"

irrigated simultaneously fr:om the lar:ger metered outlets in approximately six hours" " Such p::olonged

and repeated flooding contact of water i',ith l:he soil would be damaging for: the land and very '*iasteful of wa't.er. It must be avoided, not recommended.

-lespit,e the crass deficiencies of this docurnent it concludes '.."ith the t.estament that fast flood flow irrigation "is the iirst major change in flood irrigati-on techniques in al_most i00 years of irri-gation in Australia and is one that will cring irrigation right up to date with present and future r:equirements for efficj-ent food production,'.

It is thus necessary to emphasise that Keyline irrigation operates to save labour and water, to deepen and enrich the soil and to avoid the usual problems of irrigation land, only because the contact time of water with the land is brief. v;hich in turn is by virtue of the special techniques for the husbandry of the soil: The soil itself must be either deep and fert.j-Ie or in Lhe process of being tr:ansformed into this cond-ttion. Either way it 1iteral1y gulps in the amount of \.,'ater it needs.

A fertile soil 18 inches (46 cm) deep or more absorbs water rapidly like a sponge, and, like a sponge it holds onto the \!'ater and prevents over watering and loss to depths where the ivat"er cannot be reached by plant ronts.

The importance of the concept of KeyJ_ine perennial irrigation as a soil maki-ng procedure by the techniques described, cannot be over stressed.

I,arger Irrigation F 1ows. Some of the maximum flow tests of floocl florv irrigation were confirmed ir-i overseas countries.

In the 1963 New Caledonia pr:oject refer:red to earlier (e.fZy

22.

:rr'r .i r.r:-Lg;.lt-ion s 1..t-t:riii :i. a)v.: L t'.wo int I L j or-r E.rl lclns (nine: ntill j.r-:n lit"res) an horlr r,;as re"rdi 1y '::ontrollabl.e by one

r:peL:at,:r. Moreover t-he rles j.qn, layo"trt and construction of the project was wel-l within qrn-farm capacities and costs were low. trn the fr:llowirig year a project was designed in the Texas Panhandle with a simitar flow capacity. *

)b

*

The Application of Keyiine Trriqation For New Large Scale

initiatPublic lrrigation Development: Keyline irrigation ives have been concerned r^ri-th the fast economical irrigation of land from the steepest manageable slopes of undulating

counlry to the flattest of nfl-at' land gradients. The development in 1948 of Keyline cultivation, which j-s alternatively described as 'Patternt cultivation, made practical for the first time, the uniform spreading of rvater by flood irrigation over the ridges and valleys of undulating ,land together with the close control of the amount of water absorbed into the land" The more positive natural surface drainage patterns of the undulating land and the absence of floods were no handicap in convertinE worthless shale ridges quickly i-ntc fertile prodr:ctive 1and.

There are also historical references which indicate that flood lasting success had been achieved in 'hillsidet irrigation, notably in Northern tndia ancl South America.

It is therefore proposed that i.n the selectj-on of land for prospect.ive public irrigation developments undulating lands should be included as a first consideration, and not rejected.

Land f o.r prospective ir:r:igation should be broadened to include thr:ee general for:ms of surface qeography.

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;,inu i-|i,,:1 pi.,i:;S,esii* j:l f'rt:l,t Iiieil j.uni l-.a: long

slopâ&#x201A;Źs from t-he rnaj-n r"idqe to Lhe natural- d.i:airrage line" Such .l and in the fuLure could prove most for valuable for long term producLive irrigation a wider than usual range of crops; during periods of flood rains its production would be 1itt1e affected " b

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flat l-and that lies outside the present or recent f lerod plains of the rivers: It is typical of this land that it possesses the shapes and forms of unctulating country in profiles too low to be observed by the unaided eye. Its present surface forms have been imparted more recently by rainfall and the action of shallow run-off water and not by a series of deep flowing floods" New land of this category will be the most economical irr development costsr it will support the largest irrigation stream flows and permit the lowest operating costs by reducing irrigation time from many days to a few hours. flat land that is now or has been recently subjected to deep flowing floods. While often appearing very uniform and flat much of this land is characterised by hollows and rises of low relief and by the shallow depressions left by old flood channels " It is more costly for development than category rbr because of the earth-works needed to reduce rises, fill 1ow places and to produce artificial slopes or special gradients " Because of the initial fertility of 'these this class of land and because large irrigation flows offer a newfound measure of control of water insoak, it should not be neglected. However where g:round water is sa-line and/or shallow its use for perennial irrigation shoulci be carefully restricted.

24.

The AppLication of Keyline Irrig'ation Involves Conside::"rtions fc,r: the iti-sLribut-ion of I'Jater.

Ne',v

Design

rvith selecLed undulating land added to the category of prospective irrigation l-and it becomes increasingly advantageous to maintain the major distribution channel-s as high on the }andscape as practica.l and to irrigate land inuch further out f rom thre ri-vers " It would then be possibl-e to f ill many farm rlams by gravity whereas most dams to be supplied fronr present distr:ibuting systems would need to be f i l leci by pumping .

1r_L:1;].tl_

Secondly since the pur:pose of distribution in Keyline irrigation is to enable water to be stock-pi1ed in farrn dams either by gravity or by pumping, dt a rate of flow that wilt replenish the dams between irrigaLions, it is not necessary to supply

t

water to all i-rri-gation farms at a rate nearly as high as the present five cusecs" For example, assuming on an irrigation farm that 100 acres (40 hectares)- of land requires five million galIons (23 million litres) of water from the farm dam to complete one irrigation of the 100 acres and that the time betrveen irrigations is ten days or approximately 250 hours: irrigation of the 100 acres could then be completed in four hou::s or less and the dam could be replenished with its five million gallons (23 million litres) before the next irrigation by a continuous flow into the dan of only 20,000 gallons (9],000 litres) an hour, which is less than one fifth of the capacity of the Dethridge l{heel" irr:igation farms are uniform in size there would be economic advantagie in providing water at a lower rate of flow on a continuous basis than the present higher rate intermittently.

For fitling farm dams betvreen irrigation cycles, a lower continuous r:ate of puriping is more economical in capi-tal and running cost,s than pumping four times faster for one guarrter of t-hc time. Moreover the lorn,er delivery rate f or f'atrms of 100 ilr.-'rL1 : (4 0 hectar:ers ) nay allorv the substiL.utiorr of opcn :;rrlr1rly channeis b), rclatively sma1l and itrcx;rcnsir.e pip,i.r1ir-r,ts; t l'rat i{ou ld pr.cvent rvater loss ancl Irtrhere

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-

other proLllems f rom channel seepagcs. Furthermol:e the pressure in the pipelines should permit a direct flow into the farmers' dams.

J

(Since the value of water can be expected to advance faster or tha.n t.he qeneral rise in other major: agricultural industr j-al commodities, it would seem ttiat Australia shoul.d now i-rse iL.s abundant pipeline materials to gain in the rapidly arriving future the maximum benefit" from its increasingly nor:e valuable but limited water supplies " )

Thirdly it is proposed that the Structure Pl-ari for: new irri.gatj-on districts be determined accordi.nq to the principles of the Keyline Grid"

t-

In explanation: past and present land planning including and irrigation districts that for farms, towns and cities produces a grid system of roads as a Structu.re Plan which

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provide;

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l" 2, 3"

access to and from the new area movements from place to place within it and produces the master subdivisions of the land sr-rch as the sections or suburbs of a nerv torvn or ci-ty, or boundaries of individual or groups of farms of

an irrigation

district.

Even where no Structure Plan or plan of any sort was produced ini-tiaIly the infl-ux of people and the need to divide-up and allot the land caused a grid system to unfold albeit haphazard, disordered, and containing the roots of

major environmental problems for the future.

The smaller divisions of the land ilown to the streeLs with their house blocks or the farm and its paddocks, InusL be made in general conformity with the original. gr:icl . If the Structure Plan has been rvrongl.y cleterminecl not}ring lvi-uh-in it rv-l .l L be as i t- shor-rld ha,,re becn: t-he- ttcc-'locJic;r1 b.rl.;tucc of 1-ltc former envir onttierrt rvill suf f r--:r Illlatcr.l:;sr;'tt- i Ly' ittsr--tl;trl of L1

26.

bcincJ enhanced.

lIl seenrs that not only 1\ustralia bu1- practicalJ-y every country in the world is experiencing many envir:onm"ental hassles now that- were created largely by past inadequate land planning" The problems affect all uses of land from towns ' ciLies ' irrdustrial and mininE complexes Lo rural areas and national parks. ) The Keyline Grid differs from ot-her p::ocedures or lack :f them for determining the Struct-ure Plan" It alone croduces the Structure PIan on the basis of 'water lines" ?hree of these particuJ-ar water lines are natural in both

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the rural and urban landscapes and others are artificial' The natural water lines are; t. the contour lines of ponds, Iake and the sea shores 2" the water divide lines that tie along the main

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ridges which d.efine the large catchment regions of the river, and that lie along all the lesser main ridges of catchments within these large catchment

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regions and the water drainage lines of the creeks ancl the rivers

On the medium undulating l.and where the concept and development of the Keyline Grid originated, it imposed two off-contour new water lines across the land one above

the other and high up torvards the rvater divide lines of the main ridges of the minor catchment regions of which the farm rvas part. The first line was an open channel which interrupted run-off from rainfall and diverted the water into constructed on the farm dams equipped with outlets *The primarg va7leq is the keylines of selectecl primary vaIley$'

-ft can be srra-lJesf artd Ltighest tqpe of val7eg in ang catc"lunent reqion' irlentified as the usua-Z grrassed over v,tLleqs of the farm fands' The kcylils c;f the primarq va-l7et1 po.';:tions the h;qh':st possibfe vafleq site '7'he }<c:ql rIre-s of f'or rvatcr storagr: ln thls hl-c11,'e-s{: vaJ Lr:i1 of the land' ",.r,1

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1iile rvas also a,!-; fi. r l, ilr..rIrr, ' I l-.;r.t i. oI cij-i.f r',rent rorm: it was placed immediai:ely helcr,* the datns i,o f loor1 ir:ri-gat-e the land below. I{her* L.}re slopes of the primary ridges?'and the primary valleys wer:e long enough Lhe pair of channels and their associated darns were repeated down the iand. *-\ primarg ridge Ljes on each side ot: everg primarg val7ey and is the )argest indi.viduaT 'shape' in the landscape" s.j(-:a-)nd

Ire natural water divide line <>f. the main ridges and the ratural drainage line that it almost cornpletely surrounds ra any catchmenL region, large or small, do not contact each cther. However the two ner.r water l-ines across the l-and, bY crossing over the water*divide lines and the lesser drainage lines: join up with Lhese natural water lines 1.

2. start the formation of a grid of water l-ines and 3. divide the catchment region(s) they .traverse into rwater' zones,

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The Keyline Grid is completed by a third gr:oup of water lines located down selected primary ridges for the transfer of water from a hi-gher to a. lower channels-and-dam system" These Iast water lines may be in the form of a flat grassed channel resembling a narrow irrigation bay, or a pipeline.

They divide the 'zones' into smaller units.

The l-and units of the 'zones' may represent" in the irrigation district-situation, one farm or a group of farms, according to the length of the slopes and to the shapes and forms of the }and. The units tend to be larger on the flatter lands, decreasing in size as land is more visibly undulating.

lvith the completion of the 'grid of water lines' the principal road system is nor,v determined in conpatible relationship rvith the individua] water lines.

Roads thus follow along the water divide lines of the nain ridclcs, arl)ovc tltc clranncls, and up ancl clown beside t]-re r,vatcr transf or Iincri on tiie sclcct-ec1 primary ridges.

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28.

'l:rrs inlile of clctermininql t.irer Stri,ict-i.irt: Iria:, or Er:i"d fo.r unclulating landscapes applies in like inanner to the so-cal-led flat lands. ThaL on much of this land the shapes and forms have remained unobserved, no doubt accounts for the lack of appreciation and consequent non-"use of the valuable irrigation potential that unfolds when irrigation rvater is applied in accordance with these so-often overlooked landscape factors" Furthermore the past dominance of the 'straight line squaredoff' concept of structure plans has compelled conformity by the practical. irrigation farme::: to c::eat-e his own water shapes and slopes by resorting to extensive earth moving, grading and smoothing in condi.tions where none may har.'e been needed if the land has been subdivided with greater landscape appreciation.

There have of course been planners who rejected the squared off structure plan and introduced wide ranges of geometrical patterns" Others have favoured curved lines and it has been noted that some of these had the appearance on paper of the Keyline grid. However such appearances proved to be superfi-cial since the curved lines rarely related properly to to }and form and never tc the fundamenLal need to plan and t-o prornote the ef f ective control and benef icial use of water " The straight line squared-off type of structure plan is abnormal in any landscape. The alternative to this seeming 'order' is the simple planning of the }and in accordance with its shapes and forms that govern the natural movements of water over the 1and.

roads that lie along the main ridges and beside the major supply channels forrn sweeping cul:ves. Every road line of the new landscape emphasiscs ;errii does not disguise t}-re -in}-rerent shapes and forms of thr: lanri"

Thr:s the principal

baiicc1 planr-rinq of se colrd.rr. l' roacls, f arnt access roads , ancl roads ancl tracks rvi titin t-he irrdivicrual f arms, suit the i trnc.l arrci the novencnts o I r.lzrt',c]- ovcr thc 1anc1 . Natural s;ttr- f ;rcc ctrarinac;e Iir-res crI-C not- i,n l.cr-rlrpt-ccr bu t emphasised and

Thc

clc

29

madâ&#x201A;Źt rnore st-ab1c ancl

c:

If r.cLive

n short- the I(eyline Gi jC prcvir:1e:: ..i sL j:uct-ur.e p1.rn ii,rr cach indivi dr;a-I land pro j ecl_ r*l-raL i,ncr:r.pr:rat-cjs a sys Ler,r of complete water contrr:l and a compatible roarls and subclivision layout that does not interfere l.;ith the inaxiirum use of vrater resources and is unimperled i:y ivater and its movements. The structure plan thus pern"rits Lhe realisation of the fullpotential of the lano .;vhicl: in tlie f jnaf analysis clepencls on hovr the water is employeci. f

There Is A Further As ct cf i'Jater That Should Be i4acie Clear namely its differing c-Lasses and their relationship to Keyline planning " There arer four general classes to be considered

1.

I

2.

3.

4.

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rain falling on the land and soaking directly into the earth the run-off rvater from rainfall vrater brought to the particular area -f rom an outs_icle source, and ground v;ater "

The landscape itsel-f ancl the production from the land can b,e greatly enhanced by the application of 1ogical planning to any of these classes oi rvater" Hortever, for determining the all- important structure plan the simple rule of Keyline isi'planning must be based on the ivater of g:reatest landscape signif icance' . Each class of water ivill satisfy this crj_t.eria under oiffering landscape circunistances but there is no question-that for irrigai_ion djsl-r:icts, class (3) prevails water brought in from an outs j-de sollrce.

Since the value of rvater is increasecl by the height of the supply and by being used closer to tl-re source, the positioning of the main supply cltannel or conduit for irrigation under_ takings is a paramount ear: ly cons icleration . Once its position is deter:minecl in pr.opcr: relationsliip lvith t_he ntain ridges, all ot. licr sjcloctions anc.l scqucnccs of thc: structurc planrrirrg pI-o(-c!j:r fo11or.,, .in 1o<1 ic;r1 c>t c1cr .rs <r_.1..rc._r(ly c.iiscr"rssed.

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Tht r,lciii'i lance of t.hc l ine of r^rate r supply irr i hr,' 1;r lr.ir-riri.,|on t-.f t_itr. ::.;t_rUCt_Ur C: plr_rn f Or. irrig:,1 ,ci.,..rr-t rrI'rJ j(.i..i:,, ilt,:.:: i.)()1. di-"'ort-:r: other s.Ji,trces of ivater froil bctte:fi.ci-;:-L ir:;c," 'ihc value *f clirect rainfall in increa:;ed: run*off from rai-nfall is automatically controlled and, where the land is of more positive slope, may be stored above the lower land. Where it is appropriate, run-off from rainfal-I may also be stored below the level of the land and pumped to the farm irri-gation dams for later use.

The Patterns of Drainage" Rain 'waters' the land with some degree of uniformity but when run-off occurs, water leaves the land to join t-he streams by the shortest ancf steepest

path; there is thus a natural rapid concenLration of the v,rater but no spreading; the natural design of the land supplies only the perfect surface drainage pattern"

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It is a feature of the Keyline irrigation j-ayout that i-n periods of general overflow it provides its own efficient surface drainage system but with the added aflvantage that the flow of water can be controlled and spread widely and uniformly over all t.he land which then sl-ows down its movements and its concentration time, or alternatively, the rate it leaves the land to join the water courses can be speeded up by closing the water-gates as desired to cause a faster florv through bays that are left open.

This simple aspect of planning, coupled with the enriching and the deepening of the soil, provi-des, purely as a coincidental, a ver:y poiverful measure of f lood control.

The Application of Keyline to Presently Operat-ing Irrigation Districts and to the Individual Farms i{ithin Them. It wor.r}d not be possible to change existing distributing systems as quickly as present f arms cor:Ic1 be ad justed for: Keyline irrigation,'therefore any new s),st-en should operate by using the present f 1ow of water t-o Lhc f arlns at the particular times the water is available.

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Since impeclinents to rcpi anninq trave becr-r cr cir t.ccl by the present layotits and mcthoc'l s; of t-r r: iclation and by the Ioc.r t ion . . ./3t

31.

.-ir.ics, l"cyli.rii: c;lrll'Iot lrt:r rC'r,,r rji' -r,l -i 'ulive.i:si-rl friln.lale;i fo:: qr-rickly soiv.t.n!l i1l-i iht-r prc-.'blcriis, createcl by past J-rrigat-ion on every incilviCual fai:m. It can be expecLecl to apply in a favourable ruay to most farms and that the economics and the scope of its application rvill improve and widen as the areas of land to be redesigned are larger either in bigger farms or in new layouts that include a number of adjacent farms. ol ialli,

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In the early selections of irrigation farms suitable for redesigning there are certain crite::ia that should be noted. Firstly the size of the irrigation area should be 80 acres or more. Smaller areas should not be attempted initially except rvhere slopes are more positive and a Keyline 'pattern' undulating land irrigation layout is a suj-tab1e and low costing alternative to the time consurning irrigation of the many bmall bays of border check systemsSecondly, since one new large irriga!.ion channel may replace three or many more farm irrigation ditches and five to twenty new Iarge bays may replace from 100 to 300 small bays, it is essential that adequate It is sir.rple enough maps of the land be available. to plow-up and smooth out old borders and to fill farrn ditches but it" would be a great advantage in determining the new layout to have a contour map of the area as it was before the old layout rvas formed" Thirdly the shape of the boundary of the selected farms For example, or B0 acre (32 hectare) is of significance" farm 4A x 2A chains (800 x 400 metres) is more favourable if the down slope is 40 chains and the length across the slope is 20 chains because an irrigation channel only 20 chains long r'rould t-hen serve appuox-i natcly 8 bays 4 0 ci'rains long ancl requrre 8 r,vatcr gates" tru'hetl bhc position is r.eversccl the irricyatior-r ci-r;-tt'lnel ivould be 40 chains long at-icl ser:ve ](, ba.",s onlv 20 chains long ;rnd requir:c t.r,vicc: aS nl.llly hrctt,Ctr-cjart cls; . Narrorv and lonql , nol. wide ancl sltor t, F'or-rrtLr11, :r.i ncr. t lr,-r \tattci' f'rtr^ i.r riqatrorr is Lo bir ;lccLlrnLl ,'l atccl iri ,'.rr-ir a:rs t:c1 rripp"6 t.,,.i,t-l't 1.at:qc 1ri.pi.'

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inst.il(:er 100 acre.s {40 hect.iresr ()f rr.rirl ,rt'ir.rn and h7ot1ld require 5 miLlion gallons 123 nillion I itres) for each irrigation.

A ring dan rvith a \./at"er surface area of up to 2\ acres {f hectare) r,ray a suitable dam in inany cases. It should have a supply point nearby and be located. upland of the irrigation area. .1

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There is no need to discuss here the details involved in redes j.Eninq present irrigation f arms. There is ainple expertise and equipment available for the actual rec<tnstruction" There is however the matter of the construction of the new farm dams that ivill be needed for the implementation of these proposals.

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Farm Dams tar irri gation purposes wherever practical, as well as for stock water, are regarded as both the most

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important and the most neglected rural structures " This submission envisages a much more dominant role for them in public and private irrigation developments.

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There ar.;- twc aspects of their more rvidespread use that should be considered" Firstly, the construction of the rnan), farm dams acco::ding to sound engineering standards presents the difficulty of engineer:ing supervision and secondly, new types of dams are needed for the rapid flood flor.r irrigation of fl atter I ands.

The Keyline Dc-rub1e Vibration Earth Dam Construci-ion Ilethod and the Lockpipe system is of fered as the ans\./er to the f ir:st of these considcr- ation.

The trr,o el-e ments of 'double vibration' are f irstly, a particr-rlar pattern of movements of the bulldozer that makes use of its vibrat,ions for consolidating i:he earth as it is plac--cc1 to icrrrir the rva,lI ancl seconclIy, a series of explosivc chitr<1t s; Llr;rt- al c f i-recl undcr \vat.e t immediatell, tire cl,rnr i s i'i Llccl l. l.riit- prorrroL.cs Llrc f.ina1 rapici se t tlcnent. of t.lro r..,al l

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Asp r:cts of Dam Builciincl in KeyJine I.i'o j ec t-s . ,' , ', i,,... i.r(.)nst-,ruc1-ion of' lal\.i9: r:,,: ri; '1 ,r

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Tn the , , ,. r ,., l is; rr-ilrrrâ&#x201A;Ź,aj on Lo the vlall. s: l-e anii :-i)r'i:;-.,1) i li ]ilt i zt;n l--;r l j,;ryer:s c-rf Lrnifrirtn thickness alonq the 1cn,1 st-ctir..r;t al the w.r11" Hater is lrenerally added t-o maintain a precj"se moisture content- in the material and each 1-aye:: is compacted continuously with rollers of various types; t.he earth for tl-re wa1l is selected with care and the work is closely supervised. However, for smaller structures, including these particular farm dams, Lhe restricted size of the job vrith less equipment moving earth at a slovr rate, the cost of engineering supervision is disprop<;::tionately high and ls usually dispensed with. Therefore withourt supervision, materi.al- selection, moisture content, layer thickness and adeguate compaction often go by the board" The general result is that when orthodox methods are attempted in these circumstances the fail-ure rate is equal to that of earth dams constructed haphazardly with a bulldozer pushing the earth up the front of the wall to spilJ- over the back until the height, size and shape is reached. -

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The surprising thing about earth dams constructed on far:ms in such haphazard fashion is not why they sometimes breach but why they are so often quite successful " The answer appears to be two-fold.

Firstly, the vibration from the constant travel of the bulldozer l:ack and forth, settles the earth on the water side of the wall much better than i-s generally appreciated. One has only to stand near a bulldozer working on an earth wal1 to feel the vibrations transmitted through it" Secondly, the movement of the machine up the j-nclined slope on the cross-section of the rising rvall tends to form laminations rvhich of f er an ideal resistance to possible water movements. I'or example, the horizontal l.aminations formed on the long scction of the ival I by orthodox engineering constrlict- jon r,vhich is not properly supcrvised, could allor,v r,val--er to ntove between dnlz laycrs formed and promote 1:reachincl of the w,all-, rrrhereas hr;lt-cr is o6rposed by .l santjr.;-ich of lariiirr.t1. lons i.rqor-rarlly ac:I-()::rs it.s p;rli-r as lcft ]ry lhc Lr[).'r.ii iorrs of t]ti: brrllclozer-.

11

'I't, Ir\()V(-r t ltrouclh thc rvri.l. l / \vcrtc!- ltrrr:..i t ltir:: lrl'r,:.lli ti-ir-oLrrlh rrrrrl al cro!;si thr: nrarny I;i1'c:t ::.

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34

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1i'his I ine of r:easoning suggest-c:cl .1 rrcl-irod o I ear Lh r].inr construction that could be supel:vjsect lty tl're farrner or contr:rctor without dependence on qualified engineers.

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t ',^'as devised for the somewhaL larger-th;rn-usual farm water storages that are advocated as part of the Keyline development of rural- land" However it. has applications; beyond this fie1d, particularly for town water sr-rpply v:here suitable material for the dam is available nearby such as from the pond area immediately upstream of the r^ral-l- site. f

The Lock lJ stem is a single oi: dual water outlet in the base of the dam: a large valve releases vrater. far irrigation and a small tap may control selected vrater for domestic and stock purposes. The system is designed tc-r lock jnto the foundations of the earth wal"l and to avoid the hazard of water moving along the outside of t.he pipeline and washing through the waI1.

In combination, the Double vibrations dam construction method and the Lockpi-pe systern provide f irstly, ef f icient and economi"c water storaEe on farm and grazing land ancl for -local town supply; secondly, the gravi"ty release of the stored water in high volume for low-cost rapid irrigat-ion ol: for other purposes, and thirdly, rvater of the best- quality avail-able from the dam when required for stock to drink or for domestic supply" The following side-lined paragraphs give details of dam building ,in Keyline pro jects " Ilay they be taken as read or di sctission postponed?

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The movements of the bulldozer in Double vibration are designed to employ and to emphasise the fuII earth-consolidating ef f ects of the tlvo generally unsuspectecl f actors just mentioned and to lay-in the earth quickly and cheaply. The later vibration f rom several explosive charges f irecl uncler-rvatcr near thc toe of ti-rc rvall,furt]'rer adcis to the rr,rtcr-holdinq ef f iciency of the strur:turc b), pr.romo.t-ir-rc1 thc t apicl scL,t.Lcnrcnlo f t,he cartit .

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Essentially the wall is built so 1_hat, the ba.ck (oLrtsicle) batter is main'taj-ned at its cor"recL posit-ion and slope thr oughout the construction, r,+hi1.e the j nside rises f rom a Iong flat gradient to gradual1y steepen as the rvork proceeds, The slope of the l:rack batter at every stage of contruction is rnaintained at a constant 1 in 2h ot: 1 in 2, as the case il&1; be, while the insicle slope fr:om the front toe of the wall will steepen from very ffat to the final batter as the construction proceeds.

The sloping lines of the diagram, fig. I, represent the maximum cross-secti-ons of the wall at_ succeeding stages of const-ruction.

(1}

8" FLOAT BUOY

(4) 1%" BORE

COR RUGATEO PLAST!C PIPE

(3) FLOTA.FILTA INTAKE

(5} JOINTING SOCKET

(2'6" with spar6)

(6) VOLUME STRAINER (a) 1" mesh (b) corrugated piastic pipe

al jointing sockat bi 16 guag€ rcre€n c) aluminium rods

(c) jointing socket (d! Humes-Lon pipo

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{3) FLOTA.FTLTA

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i1} 1%" 8OAE HUME.S-LON

(2) SYNTHETIC FIOPE

(6} VOLUME STRAINER

{8i 25'' STEEL PIPE (9) STEEL BAFFLE PLATES (a) 25" pipeline -" (b) 'U'section rubb€r gasket (1Oi 25" VALVE (Patent applications) lal 1%" standard valve and fittings.

Finishes at a Hum& S-Lon elbow readY

(9) STEEL BAFFLE PLATES

."#ffi", ,,,

PIPE

{or taks-off for

fit;"'

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underground lines arrd 51ock troughr

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I in 2 battsr

(3) {

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50" (s)

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Fig" I

Each time the bulldozer arrives at the 1ine of the inside

toe of the vrall with a f u1I load, the blade is raised a Iittle to spi1l a thin Iayer of earth of slicll-rtIy increasing th,ickncss t,orvard the linc of tl-rc ba-rck bat.t-cr-of thc i.ral1_; the spil1ing of eartl-r dorvn the back battcr: j s; a,.,o jr,l cci. The bulIclozer 'rLln' is usr-ra1Iy in sccor.rC c]o.lt . i.ihcn i:hc. loac1 is lJone t-hc t]:act,or continuc:,; a 1it.t Ic f irr-Lhcr s() l_1-rrrt- aII

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the eart.h as it i s placr:rl j s t-r;rvcl

Icrr-l b',,

t-he t-racks.

If the Load contains lunps o.i *:.rr. Lh, r.,riLv tl-r: f jner rnaLeri,;ef escapes under the blade during thc r:ar1y staqes of each pass, thus ensuring that t"he best mater'ia1 qoes whe::e it r-s needed most on the water side af t.he centre-line of the wal1" This fast spil1 run also promotes uniformity of texture from the improved mixing of the material which 1n turn favours even settlement, while the vibrations from the fast return of the empty l:ulldozer dorvn across the rising wal1 after every pass further: ensures the consolidation of the earth.

The diagram, FiE. 1, illustrates the water-resistant effect of any J-aminations which may l:e formed in the earth of the wal1

"

The failure rate of particular types of construction for earth dams seems to be more closely associated with the moisture content of the earth when it was placed in the waIl than rvith any other construct-ion factor " Where the earth is obviously dry the rvall is more likely to breach, but if the earth used is moist- when placed, the failure rate is l-ow even r,vhere the construction methods may appear to be inaclequate"

Earth l4oisture.

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The method of Double vibration with its thin tapered layers of earth deposited at fair speed makes improved use of the finer material by placing more of it in the rsater side of the wa1l; moreover, the same action appears to make better use of scant moisture by mixing the mat.er-ials better.

However,

while the construction of dams ivith earth that is obviously dry is more hazardous it has oftcrn bcen done of necessit-y and successfully.

Double vibration apparently makcs tl-re walI more resistant to drying out when a dam is cmpt-1,. tror instance, follorr,inc1 a dr:y hot spelt in the Cor-rnty of Cr.rnrberl.ancl - Sydncl, slrrror-rnr1 Lrvelve empty sizeable irr icyat ion .rnrs; c)n sc:;rt Lercd f arnts breached after: they fillcd s;udclr-.n11, in ho;,:.v1, r;ri.nfalL ancl IraC to be repa irt'd . , -r_ c1

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i{ovr:ver, of the riany â&#x201A;Źlilrl;t_ii il;rnrs iir Lt're ar ea that \verc built by the Doubl-e vib.r:ation methocl, ncne breached when they f il-led quickly from the same rains.

It may be dif f icult to loe al:solutely sure of the ef f ectiveness cr otherwise of specific dam-buitding t.echniques when earth and weather conditions can vary widely during construction" Even the cause of a breach in a wa1l is usually gone by being washed away before it can be seen. Horvever a great deal can be learned abouL the condition of the earth wall of a dani filled rvith water when explosive charges are fired under-water near the inside t-oe of Lhe wall" The vibrations rvhich can be f el-t by stand.tng f lat-f ooted on the wa1l, clearly indicate its compactness or otherwise.

E

The Lockpipe System includes a large diameter steel pipeline

E,

which is placed in position on the wall site of a dam during the early stages of construction" It consists of lengths of steel pipe covered inside and out with an anti-corrosion coating and- joined together on the site.

The system provides a number of baffle plates of sheet steel that are bol-ted in pairs along the pipeline" They tighten onto the pipe through U-section rubber strips and are designed to prevent the movement of water along the outside of t.he pipeline.

(See diagram. Fig. 1. ) A Cone Strainer fits on the inside (water end) of the pipeline of the Lockpipe system. It incorporates a grid to stop water-l-ogged rvood and other obstructions from entering the 1ine. The meshed opening of the cone strainer is several times larger in area than the cross-section of the pjpe, r,^rhich ensures that rvater: rnoves into the cone ntuch slorver than its speed througl-r the pipel ine. Anything that passes the grid must thr_rs florv on t}'rrough, making thc system virtually irnpossible to choke. it s on tlic or-itsidc relc:ase oi bire st,orocl rr,atcr

1r Val.vc f

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oI the lockpipe for the s;ma 1 -1. rr.r lve f or ['lot;r h t-

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filta lvhen ncecled is incorpor;rterd in t-he sice o, f t-his L.rrc1 c: va1ve. It is designed to providc- stock r,..rat-cr from nâ&#x201A;Źlar: the su:'face over the deep water of the dam vrhere the quality is highest.

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The steel baffles of the Lockpipe systern are more numerous on the pipeline than the more orthodox cement collars and are spaced in a special raanner. A baffle plate is placed around the pipe on the centre of the line r,vhich is directly below the middle of the cr:est of the cornpleted daro. From the cent-re to the inside (water side) the baffl-e plates are placed a distance apart equal to or a little more than one third the depth of water above the Lockpipe. For instance, if the depth of water is to be six metres, the baffle plhtes are about two metres apart with the last plate on the water side of the wall one metre insiCe the earth of the wall. From the central baffl-e plate to the back (outside) batter, one baffle only is used for each length of pipe and placed L2 inches (300 mm) from the pipe joints.

These l-ast baffles do nr:t need the U-section rubber strip.

The steel baffle plates and the simple techniques for beoding in the Lockpipe system are designed to stop water movements before the central point of the pipeline" If some rvater does by-pass aI1 the baffle plates on the water side of the wall and the central p1ate, it meets no further special restrictions.

If seepage water is restricted beyond the centre of the wa1l, such circumstances may aIlow the build-up of pressure and cause a blow-out sitrration on the back face of the walI, whereas a seepage at the back of the rvalt will usually stop of its own accord in a year, or be sealed off by the explosive vibrations.

NearIy aIl earti-r dams seep some rvater: r p&rticularly f or the first year. Double vibration dams may also seep, but it is not unusualthat seepage does not occur or is greatly reduced or stopped rvithin ten days af t.er- tirc \va-ll is vibr:at*ccl by explosives -

I

I T]'rc area round the l,ockpil_rc is; i1 csic;ncd t_o be the most

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39.

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st.rltlc: secl-ion of thc-, vial1. Tf a 1r:.ri: Cor:s; oc(lLit: irr 1_hr: wall it is unlikely to be assoc:iatecl viith Lhe Lockpipe system. Further details of the system such as laying, bedding-in and construction detaits are not requirecl here

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Explosive Vibration" A series of small explosive charges fired under-water near the inside toe of t-he waf tr provides the second series of vibrations of the Dor:b"le vibrati"on dam building method" The vibration force transmitted through the rvall by explosives depends on the depth of water. Ilalf a small ptug of gelignite may give an adequate ef f ect when f ired und.er 2A feet (6 rnetres) of water, but a fuIl plug will be needed ivhen the depth of water is 10 feet (3 metres) " If the water is only one metre deep the one plug will not produce effective vibrations in the wal1.

For the first shot a spot is selected on the wall near the deepest part of the dam and the fuse lighted.

The lighted charge is thrown to hit the water directly above the line of the inside toe of the wall. For example, if a dam has one in two batters and ten feet (3 metres) of water, the charge is thrown to hit the water 2A feet (6 metres) out from the water's edge at the wall" The operator stands flat-footed, facing the pond on the crest of the wall near the water, and waits for the explosion.

The explosion vibr:ations will be felt immediately in the feet, but can be missed if t.he heels are of f the qround. Tl-ris first shot is satisfactciry if the vibrations are felt qr_rite positively jn the feet-. If not, the charge may have been thrown too far out into the rvater.rnd come to rest on the solid bottom beyond the il-rsicle toe of the lval1. Anothcr shot ,is then f irei to rcpl.ace thre i nef f ect-ive charrqc.

Each charqe is f ired scparately s ince a I iqhteci charrqc ir-r the r.vater rvhen anol,her onc f ircs can bc extinquis;hecl by Lhc: cxplosior-r, thus lcav inc-.; aln uncxploclecl charcle in Lhc. c1arn. /

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ilain

CtalltS j-s; t-.:,; o-f

at rt i r",:,.1.1 i. i.-,, r i'r)I::-ti i:,.t<-'t-r:tl i-r'i)tit

araltth t.aken from ins'i ir-.: the (.ialrir .t l('rr,r(:. t{,i l-1-ri: lva l i " f'or example, a ring dam t-o hcld the waLi:r: 'i-c-': f 1oocl f -Low irrigate 100 acres (40 hectares) in four hour:s ntay have a circular wall about 120 yards (110 metres) in diametr.r and l0 feet (3 metres) high" The centre area of the dam would be then undisturbed land surface surrounded by a ring trench 30 yards (27 metres) wide vrhere the earth was excavated to form the waII" A 25 inch (62.5 cm) or lar:ger Lockpipe system through the base of the wall r,vould release the water rapidly into an irrigation channel.

A dam of similar depth and douLrl-e Lhe diarneter would hold sufficient water to irrigate 400 acres (160 hectares) of land in eight" hours" The larger ring dam has a higher water storage ratio per unit of earth moved than Lhe smaller dam but further increases in diameter are limited by the l-ikelihoocl of" wind/wave action damaging the waI1. For inst"ance an area of 800 acres (320 hectares) of irrigation land j s better served by two dams than by the one larger dam"

Ring dams can be f illed only by piped water: or: i:y pumping.

The pump and power should exactl-y suit the work to be d.one during the time the supply rvater is available" ff the source of supply is permanent the smallest capacity pump is used that will discharge the requi-red amount of rvater: betrveen one irrigation and the next" For example a pumpinE rate of 85,00O gallons (380,000 litres) an hor:r v;oulcl provide over 20 million gallons (89 million Iitres) in 250 hours which is sufficient for 400 acres (160 hectares) of irrigation.

It is to be noted that 85,000 gallcns an hour is somev;hat less than the capacitl,. of the Dethr:idqe rr'hee]. (Tf power is to conle froni electric mains it cor-rld be t.h.rt- a lai gcr pump using po\^/e r at night rates miqht be tl-rc bet-_ter cleaI. )

The most efficier-r1_ closecl*rva1l. clanr is Lhc rinq shapc but an\/ cl.oscd or conl-innorrs r.,,;r11 thart suits t,lrc particular: cir:cunistances can bc el.fective. / a')

42.

The Contour Dam is .r pr;rctic.r1 ancl econolnic earth s truc t ure for holding rrrrgation water on lancl with slopes rang ing

to I in

100

or a litt1e

flatter.

The dam is formed by a main wal1 of uniform height that lies along a contour: with a wing wa1l on each end lying up-1and that reach a l_j-ttle beyond the planned water Iine

of the

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=

dam.

For example a 10 foot (3 nietr:e) contour: dari constructed on a slope of 1 in 50 may have a main wall_ of any length such as 2A0 yards (IB3 metres) or half*a-mi1e (800 metres) or more according to the area of, l_and ta be irrigated, with wing wa1ls 500 feet {152 metres) -l-ongr _ height I0 feet times slope 50.

The main walI takes its pctsition fr:om the selected contou:: of the land- On a flat ridge the water in the dam lies on the inside of the curved main wal.l. whereas when constructed

across a va}ley the water 1ies on the outsrde of the curve of the main wal1.

The length and size of the contour clam is not limited by wind/wave actions as is the ring dam" If the main lvall is very long and straight and could thus promote wave damage a baffle waII in the centre of the length is used. It is constructed simil-arly to the end walls ]rut does not join up with the main contour wall. The rvater can then be released. from the dam through a lockpipe system on either side of the Lraf f le wall.

*

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COIICLUDi NG ARGUPiEi.iTS

The esscnce oi this ::ubrr i s,sion i-s {1) , Lhat the perverse and over appli.cation of \rt,1Lr.r ;:nd the under supply r:f air: to the soil are the principal causes of the problems of salinity and drainage that affect irrigation areas and (2) that. the first approach Lo the cure of these problems is the elimination of their causes.

,

J The existence of drai-nage problems indicates that ir:rigation rvater: has been used improperJ-y" The appearance near t,he surface of the land of formerly deep seated sal-ine waters indicates that- the wasLage of water has been enormous and has now added a new dimension to the ground water reservoirs However irrigatiorr

I

f,arming is beset also by t.he problems of dry f arming except water sho::Ege - including what is probably the greatest delj-nquency of modern agriculture, namely its consistent failure to return organic mat.ter to the soilfor the creation of humus as fast as crops use it up. Thus modern agriculture is a sc:il destroying process ivhich, oD its long term bent depends on ever increasing amounts of artificial fertiliser and synthetic chemicals to maintain crop prod-r-rction" Yet some of the principal rarv materials for: the manuf acture of artif icia-l- f ert- j.liser:s are, 1i-ke oi1, coal and natural gas, the concentration of special elements from ancient. fife and t"hese fossil fertiliser deposits like the fossil fuels ar:e subject to accelerating depletion.

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to believe t-hat r.;hen the rocks rich in, for instance, phospl-rates, are depleted, the living ivorlci will come to a halt? Of course this i.rill not be since the inexhaustible resources of the :;ubsoil have not been even scratched f or nutrients. \^/e

This delinquency of agr:iculture has tvro major effects on soil ar-rd on water. Iiirstly it resLricts the natural supply to plant-s of the nutr:icnt mincra.ls in Lhe soif rvhicl-r creat.cs the apparent neecl for- t,hc, evcr incr,easing application of ar:t-ifjcial fcrt-l 1is;crs, anci sccorrrl 1y, b), ti're conseqr-rent "../44

"

tL 1l

mincr.rli sation oi thc soil, rcstr:ict-s its absorpl-ir.rn capac,ity arncl r,vastes wat-er which in turn agqravates the r.lf lc:ct-s of droughts and increases the damages of scii erosion by water run-off.

Any cure of the resent. soil and vrater roblems of a riculture includ in l-rr l- ation farm must- pr:oduce ilee ferti 1e soil if the results of the 'cure' are to have any real degree of permanence

"

To further broaden the issue h.:efor-e this Inquiry, salinity is not unique to irr:igation land since it has developed ;r1so as a major problem of dry land farming. .In Wester:n Australia salinity is now more visually impressive than it is on Victoria's irrigation lands It is clear then that this Salinity Control and Drainage Inquiry involves rvide considerations of treniendous moment since the right ans\.rers will apply also to other inajor agriculturalissues including those of over chemical-isation and of salinity in dry land farming.

It is har:dly necessary to state that this suhmission rejects the general agricultural thesis that our soils are deficient in nutrient mineral-s and that their extractions from the soil by plants must be balanced by their return item by item to the soil.

The opposite view is accepted that all- the nutrient elements that are necessary for the production of abundant, healthy crops are usually present ilr inexhaustible supply in the soil s and subsoil of the land that is presently being far:med and also in those of farmir-rg lands that have nor,^r been abandoned " However r.rhile the deficient

soil may be rare, there is little doubt that Australian soils generalll, are remiss or deliquent in their capacity to provide the full range of nutrients in useable form to crops. On soils tl-rat \.JCre naturally of very low f ertility the application of p.rr ticlrl.rr 'Lrnavarilablcs' as s tarter f ertil-isc.rs itarve hac-l rcsrrlts t-.lr;tt. appeal- iriaqicarl.

Examplcs are tl"re tr:ace clements copper,col>irlt, nrr.;lybrlcnam ctc .../45

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J'a11 srti l:,; ,1,-.,.r i.,-:.1 ir .,tts,tt t.:ti i;t alncl Lhc r.,'rcl r: iriitr-l responsâ&#x201A;Źl of sLici-l l-oil:._ tc, pirosphaLc fcrL,iiisers. lr'h.it is.rlways lacking in the soi.ls that responci r:eac1i1y when .r:,..t(.i

r-,li11

nutrient minerals are supplied as unnat.ural sclluble salts by artificial fertilisers, is the biotogical activity which results from the decay of plentiful- organic matter: in the presence of adequate water, warmth and air in t.he soil.

When these are present the rate of suppty of the essential nutrient elements j-s p::opo::tional to the dynamics of this activity. ft is suggested her:e that the best organic matt_er is the newly dead roots of plants - always including legumes and t.-at this material can be promoted readily to provide more humus than crops destroy. The most fertile soils of the earth developed in this manner only because the general climatic circumstance provided the right- condition in the soil for organic matter to create humus faster than the growth of plants used it up" Most of these soils have now lost their former richness in humus and beco;ne mineralised owing to the perversity of agricultural practices.

This opinion of the value of promoting and using root mass for the rapid improvement of the fertility of the soil does not decry the worth of the plolved-in g.reen manure crops and composts of organic farming. On the one hand, while such practices are favoured even by many who follow the over_ chemicalised wdy, farmers do not often persist in their: use, believing them too costly or impracticat for broard acre farming ancl gyazing; moreover the over_-use of artificials can offset their value. On the other: hand the provision of organic matter by promoting root mass has the great practical advantage that every production crop can be manaqed so that it produces as excess of organic matter without the cost of r,.rithholding the land fr:om procluctions ancl grorvinql special crops and plorving tirem in.

For these reasons it is suggested the concepts and the techniqucs involved for promot_inq fcrtilitl. via l oot iirass including on tI-re grancl scal c cc,Lr.l cl br: r egal clccl .rs a brcak,-throuqlt of somc significance, since the costs of pt^ctc1 r-rct_.in<1 cj-ops

I

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rvolrlcl be subst.antially

::ecluced.

In tLiis matter of fertile soil anci scr-call-ed. cleficient soils it is pertinent to note Lhat on the one hand the soils of the worfd that are now said to be deficient in nutrient ninerals are 90% to approaching 100? rock minerals which still irrcl-ude the ancient and often ini-nute crystals of the orig'inaJ, rock that contain a1I the required plant-food minerals, an,e that on the other hand, plants are 90? to approaching l00g coliLposed of non-mi_nera1 substance L.haL is Cerived from the slrn/ the ai-r and water," and also th.rt drinking water, itself a t..zeak rnineral solution, will support plant growth.

Thus from the limitless supply of nut_rient. minerals that can be released and processed for ptant food by the decay of organic matter in the earth, a very fittle goes a long way indeed

!

I

As indicated above, it has been found that certain artificial fertilisers can greatly assist by speeding up the process of soj-i creation. For instance when transforming into fertile so1l a very poor clay earth that is incapable of supporting the growth of any legumer drr initial application of a mixture of superphosphate and lime or powclered dolomite rock rvith the seeding of g'rasses and legumes, has often produced a result in one year that few other methods investigated could better in three years. However, once such a reluctant earth has been induced to support legumes satisfactorily, the further enhancement of the soil usually proceeded better without further additions of artificial fer.tilisers.

Any soil from which procluction has clepencled on artif icial fertilisers, can be more rapidly corrr,,erted to a high degree of biological fertitity, by first cleveloping a pasture phase. i{here grain crops are to be gr:orr,n w,ithout this pasture phase, the too rapid recluction of ti-re Lrsual artif icial fc'r t-iliser applicatjons is likell, t.o rc:;ult in an initial c1t op in ),ic1d; buL the frropcr tirn_ino crf acr.rt_ion and the st:lcct-ion of a suit.rble leqr:ne to qlow w,itjt the crop lvitl (J()ucr..t11. 1, of f set this of fcct. .../47

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iier-rtion by cu,l.tivatic-,n, irnmediatr,:1y hefore the f ast f looil f Iow irrigation thr:ee tir,res dur:ing the warm v/eather of the f irst year. The appli"cations of water coulcl be, of course, more numerous than the cultivations that ael:ate the earth" r-.'or-r

By the end of this short period the indifferent soil and sorne of the subsoil below woulc1 have been transformed into a soil of notabl-e fer:tilit-y and depth. With the continuerl promotion thereafter: of root mass including its proper aeration as reguired, the soil would be capable of constant further improvement.

Since past excess irrigation water has now caused. a vast addition to the natural ground water reservoirs, the rvider the area that such a prograrn covered with its more effective use of greatly reduced quantjties of water - rvith little or no further additions to qrr:und water the quicker would the present artificially induced hiqh water tables recede towarcl their normal levels " The program could be expected to hasten the pr:ocesses of natural recovery that have operated repeatedl-y in the past on irrigation land after it had been abandoned.

It is suggested that the most logical way to dispose of saline water ermanentl j"s to encour:age in this manner its progressive return torvards its original Ievels rvhere it, like the sleeping dog, sl-rould no doubt have been ,1et l-ie,in the first p1ace.

This is not to advocate that other , oy l-ess permanent means for disposing' of present near surface saline rvaters or measure :; for extracting ancl using the salt should not be unclertaken where it ivi11 speed-up recovery. Hor+ever, it is proposed t-hat the problcns oi. s;alinity ancl clrainagc be isolat cd ;rncl tr-oatcc1 orr t j-ir.: s;mzr1l , scl f conta ined ancl Iocal sc.r-le rvi'rcrc possjblc lviLjt farnrcr:s closely involveci and finll-r.cccl

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:icir.tn.rs l,ir.:t coLild pres,:ent ma ioi, decisions, firiance and management. I"lorer-:veu., if t-he remedies proposed here p::oved fu1ly effecLive, any grand scheme for disposing of saline water: could sooner or later become redundant, or be effect.ive only for land on which irriEation should not have been permitted originaIly and from which it should nor,v be. withdrai,vn.

If excess irrigation water has caused the salinity cf- the soil and greatly increased for many years the lrlad of. salt carried to the sea by the Iilurray River, it must also have partly desal.inated the landl If the wasteful use of -irrigation water: ceased and many small scale measures were undertaken for disposing of saline water: and reducing sa1t, how soon would the salt load of the river decline? Intrould the river withi-n a reasonable time carry l-ess salt than before large scale irrigat-ion started?

*

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Soils of the 2A to 30 inch (500 to 750 mm) rainfall regions that have become deteriorated by farming practj-ces over the course of 2A t.o 50 yeal:s have been transformed in three years by these' methods, vr,itl-rout irriqation, to a cireater depth of f ertility than ti-reir original state. ft is subniitted that, in l-ike manner, rvhere perverse irrigation procedures over a period of many years have ser-i.ously damacJed the lancl, the methocls ancl procedures of this submi.ssion rvifI reverse the processes of destruction and recover the land to gre;rtcr: than ever prodnctivity.

Iior."'evcr the deterioration j oi l-rc so I of rnec'l iurn rair-rf aIl areas atrcl thc rising problens o i sa L itr itl, and cir a irracyc-, oll irr ig.rt ion latncis do not- of fer crxactllz l)cr]-aIle1 crons lrlcral-ions. In thc: f irst p1.ace the L.

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.lrâ&#x201A;Źr c.-iLrsr.:c1 by inadequ.rcies 1n the milr);tg(]tltc]ni_ o1. l;:.ni :1nd wale r: they can therefore be of f set kry a s,.ri.table change soil and water management methods. As tD the differences

in in scale; the recovery and further development cf the soil on a farm in the medium rainfall situation is relatively unaffected by the impoverished nature of the soj 1 on surrounding farms, whereas in a like circumstance .t:f a farm in an irrigation area the problems of salinity and drainage on the surrounding farms may det_rirnentally af fect or even prevent its recovery. In order to securâ&#x201A;Ź-, the same rapid change, the scale of t.he project may need tc embrace other affected farms. Then, by the same token, the recovery of a group of irrigation farms would beneficially affect those nearby.

Again comparing the possible results from these varying circumstances; the capacity to irrigate rapidly with frugal application of water woul-d greatly favour the more rapid development of deep fertile soil on those irrigated lands that are not too badly affected by the probler,rs of salinity and drainage. *

*

*

If the measures that have now l:een proposei at:e ecologically sound, a great saving of water must result from their: application.

The ultimate position t-hen rvould be that very substantial additional areas of land could be i-rr:igated without addition t-o the rvater presently in use.

*

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*

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fn i-i,,ii i. L ariir{.r}-t, t'}-icr<: ;_tre c>:iltitp.., t' i.r :. ,,i;,.: , .r .,. t. ,.:, i_t r-ir.1 a t,ir_,r;.i t)ri br: i-h ,lt-idr-it,at-inc1 and on .[-Ia.i_i.cr. ]r:irijs, lor,i Lr_1 br: c1r:monstritt.ecl

for your Committee" f m.entic;n alsr; i.li,r r- i-hc consul.ting arm of the l4urr:ay Va11ey Development League naniely ,G"V. Laivrence and Associates', is preseirt.ly desiqning a Keyline f 1ood flow irrigation project situatecl a f evr kiloinetres acr:oss the border in New South Wales from Srvan Hill in Victoria. your Committee is invited to examine this developm.ent with League representatives from its i-nception.

This demonstrating of Keyline rrriqatic_rr: layouts and procedures would enable judgements to be formerl as to their logic and practicability and as to their eccnomies in manpower and water. However their effect on the problem of salinity and drainage may not be so immediaiely.apparent and could thus be rnatters for interim judgements and decisions, and for observations over a period.

*

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Registered Desi gnsr Names and Co p rights Some of the items and procedures nientioneo in the foregoing are the subject of registrations and copyr:iqhts "

"

L

By statements in the Keyline books every farmer has been given the right to use all such material 'f or his own purposes on his own land'.

The Murray Val1ey Development League has the same rights extended to include 'for purpose of profit for League funds, . The sane rights are conferred on the Victorian Government should ii' undcrtake any complete Keyline project that is designed :For- them Lry the Leaque's consLlIting arm in which case thev al-c ;r:-;sur ccl of the fu1l co-operation of the oriqinator oI Iierr i i nc- ancl the lrh_rrray Valley Development Leaque.

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tlrc l,lul r:ay Va11e1' Development League to behal f . s ta temcn t s on its

The Murray Val1ey Development, Lea<;ue has become greatly concernecl by the mounting evidence of the deterioration of the land and the waters of the Murray Va1ley. It has discussed these pri-nciples with the Albury-Wodonga Development Corporation and made a submission to the Iuionarto Development Cornmission, a copy of which is tendered to your Committee. (Document. then produced).

The League has sponsorecl these subinissions because it has accepted Keyline as the most logical and practical approach for the expeditious solutions of the present environmental problems including those that are the particular: concern of this Committee of Inquiry - and thereafter for the continuous enhancement of the whole l,lurray Region.

The League hopes and expect that its sponsorg.hip of the principles and concepts now placed before this Committee will lead to the development of a more ecologically balanced and beautiful envi"ronment for the region, and one that will serve as an exarnple for the rest of the r^rorld, of an outstandingly healthy and prcductive landscape.

The League earnestly seeks the good rvil-i and active support of this Committee of Inquiry in order to have pilot projects of Keyline irrigation established so that its principles and practices can be widely displayed for: t"he judgements of the appropriate government i nstrumental it i.es , i-tie f armers and all the people of the valley.

As noted above the League is alreadl, engaged on one Keyline pr:oject. The League is rvilling to undertake further pilot projects rvith farmer co-operation on individual irrigatior-r farnis to be selected on tire basis t}-rat the f arms are already affectecl by saLiniLy ancl/or drainage problems but are judged c;rpalrle in isoiatiot-r of being fully recovered and thet-t iur l.hcr- tlr c;,rt.1y impr:ovtrcl .ts to soil and prodr:cl-irzity.

A-l t r:rn.it. ivi,:ly or arclc'li {-ion:rll1,, onc r^,'idcr scalc pro jcct cor-rld / r-'l

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52. cir-rl:)racc ai cJroup of conl-iqLrous farrl.',;::r;:.t- t'ioitlr.l I-tc scicctcd

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on a simil.rr

basis"

I,,'ith the approval of the individual rarmersn Lhe League rvould be responsible for the designs and layouts of these projects and also f,or supervision to the stage required by the farmers" Co-operatinq far:mers would, of course, provide their own finance but the League would co-operate in exploring sources of Government assistance. ft would be proposed i-hat the pi:esent government practice of providing lor,v interest loans to farmers for the construct-ion of farm dams for irrigation, be applied to these initial proiects with perhaps some degree of priority.

The provision of such loan moneys is now dependent on the approval and recommendation of engineering officers of the departments and thereafter irlvolves their general supervi-si-on" Providing that these officers had been authorised by their departments to approve some latitude in departures from their present procedures, their close involvement vrith the pilot projects would be of significant advantageo Because they have the cri"t.ica1l-y i-mportant training and ski11s in field engineering they would quickly become competent in any new procerfures when their assistance would speed up the projects and, with the unqualified success of the pilot projects which the League confidently predicts, rvould be of invaluable assistance for the wide implementation of the thenproven principles and, procedures of this submissj,on. l^lith regard. to the f inancial involvement of the consulting arm of the League, G.V. Lawrence and Associates; si"nce it ntust pay its way it is proposed that costs and f ees rvou-ld a charge on co-operatinq farmers ancl be included in the estimates for each project and subnittecl for departmenLaf approrral.

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'J'i-r:rL'r -is; alne furLhr:r lJroposal l:iral- i.l.'.,, l,,,r,rirt :-ril,irt L: t-O Lh i:-: Corlnitt-cc of Inquiry f or i i::l i:.Jit:-; icir.:r:at- iori:; anci lros:; j"b1e supporl- r,vhj-ch is an alternat"ive means of conclucLinq and

financing the pilot projects.

It involves first.Iy the allocation of money by the Victorian Government to finance say five single farms and one group-of-farms pilot project, with the League as consultant and designers, and the co-operation of relevant department officers including from, Irrigation and Water Supply, Agriculture and Soil Conservat ion

"

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+

These various proposals are regarded as a stage in the overall and principal objective of the lvlurray Va1ley Development League namely the gr:eatest possibJe enhancement

of the total environment of the Murray region and. the purity of al1 its waters from Kosciusko to the sea" Gentlemen, on behalf of the Murray Valley Development League I thank you very much for the opportunity of presenting this subinission and remain at your disposal for any elaborations you may requj-re and to answer the questions you may wish to hrl{-

Copyright: P.A. Yeorn.rns and

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