State of the art Edition 2 - VRO | Agriculture...
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State of the art Edition 2 - on irrigation farms Inside this issue • Automated Irrigation 1 • Water Delivery Efficiency 4 • Adapting to Change 7 • Centre Pivot Irrigation 10 • A Gradual Transition to Dryland 13 What change have you implemented? Rob and Lynne McCartney installed an AWMA automated irrigation system with telemetry on 13 fast flow outlets. The system was installed on their Tatura property about two years ago and services 20 hectares of irrigated perennial pasture bays. Additional stops and channel modifications were also installed to compliment the technology upgrade. The automation system on each outlet has solar powered batteries that operate the gate and is linked by radio to a personal computer in the farm office via an aerial installed on the home’s roof. Irrigation timing and duration can be programmed into the system to make the task of irrigating the bays fully automatic. Why did you implement this change? To Rob and Lynne, automation seemed to be the next step in developing their farm, once laser grading and drainage improvements were completed. The main benefits driving the installation included time saving and reductions in labour costs. They opted for telemetry over other forms of automation, such as basic clock timers, because telemetry offered a higher level of convenience. Clock timers or similar basic units would have meant there was still a need to walk around and set, or relocate, the automation units regularly. Where did you find information to help guide you? Rob and Lynne gained information on the technology through speaking to other farmers, professionals in the field and attending field days. Who: Rob and Lynne McCartney Where: Tatura Enterprise: Dairy What: Fully automated bay outlets with telemetry control State of the art - on irrigation farms Automated Irrigation Automated Irrigation System On the farm
Transcript of State of the art Edition 2 - VRO | Agriculture...
StateoftheartEdition2
-onirrigationfarmsInside this issue
• AutomatedIrrigation 1
• WaterDeliveryEfficiency 4
• AdaptingtoChange 7
• CentrePivotIrrigation 10
• AGradualTransitiontoDryland 13
What change have you implemented?
RobandLynneMcCartneyinstalledanAWMAautomatedirrigationsystemwithtelemetryon13fastflowoutlets.ThesystemwasinstalledontheirTaturapropertyabouttwoyearsagoandservices20hectaresofirrigatedperennialpasturebays.Additionalstopsandchannelmodificationswerealsoinstalledtocomplimentthetechnologyupgrade.
Theautomationsystemoneachoutlethassolarpoweredbatteriesthatoperatethegateandislinkedbyradiotoapersonalcomputerinthefarmofficeviaanaerialinstalledonthehome’sroof.Irrigationtiminganddurationcanbeprogrammedintothesystemtomakethetaskofirrigatingthebaysfullyautomatic.
Why did you implement this change?
ToRobandLynne,automationseemedtobethenextstepindevelopingtheirfarm,oncelasergradinganddrainageimprovementswerecompleted.Themainbenefitsdrivingtheinstallationincludedtimesavingandreductionsinlabourcosts.Theyoptedfortelemetryoverotherformsofautomation,suchasbasicclocktimers,becausetelemetryofferedahigherlevelofconvenience.Clocktimersorsimilarbasicunitswouldhavemeanttherewasstillaneedtowalkaroundandset,orrelocate,theautomationunitsregularly.
Where did you find information to help guide you?
RobandLynnegainedinformationonthetechnologythroughspeakingtootherfarmers,professionalsinthefieldandattendingfielddays.
Who:RobandLynneMcCartney
Where: Tatura
Enterprise:Dairy
What:Fullyautomatedbayoutletswithtelemetrycontrol
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Were you able to gain any assistance for the change?
Priortotheinstallation,RobandLynneweresuccessfulingaininga$20,000grantthroughtheAustralianGovernmentdroughtassistanceprogramforirrigationsystemimprovements,andobtainedafurther$6,600grantthroughtheGoulburnBrokenCMAfarmwatersavingsprogram.Bothgrantscontributedtothecostofpurchasingandinstallingtheautomationsystem.
(SeeResearchsectionbelowfortypicalsystemcosts.)
What was the result of the change and was the investment worthwhile?
Asidefromsomeminorinitialproblems,RobandLynnebelievethebenefitsofimplementingthetechnologyhaveoutweighedthecost,particularlyinreducingtimeandlabourinputs.Quantifyingthesebenefitsisdifficulthowever,becauseinlargeparttheyinvolveaspectsdifficulttomeasure,suchasimprovementsintheirlifestyleandcreatinggreateropportunitytoworkonotheraspectsoftheirfarmbusiness.
Were there any set-backs when implementing the automation?
Althoughtherewasnoexactblue-printtofollow,RobandLynnewereabletogainenoughinformationtomakethetechnologyworkfortheirspecificfarmingsituation.Thereisnosingleautomationsystemthatfitsallcircumstances–sodespitefeelingwellinformed,therewasaslightlevelofriskingettingthesystemcustomisedtotheirfarm.Therewasaninitialperiodwherethecouplefoundithardtoputtheirentiretrustinthesystem,untilithadproveditself.Theystillfindirrigationdurationsometimesrequiresadjustmenttoavoidunderoroverirrigation,dependinguponthestageofpasturegrowth,grazingpressureandchannelsupplylevelvariations.
Alackoftraininginutilisingthecomputersoftwarewasidentifiedasaminorissue.Theyfoundthesoftwarewasnotoverlycomplicatedandcouldbeinstalledontheirexistingcomputer.Why do you think the change has worked?
AutomationwithtelemetryhasworkedwellonthispartoftheMcCartney’sfarm,whichisbasedonperennialpastureirrigatedintensivelythroughouttheirrigationseason.Themajorbenefitsareinlabourandwatersavings,andsoinvestmentinsuchatechnologyupgrademaynotbejustifiedonirrigationbaysthatarenotirrigatedasintensively,suchasthosegrowingannualpasturesandcrops.
Do you think other farmers would be interested in this change?
Theuptakeofthistechnologybyotherirrigatorswoulddependonafewfactors,includingfinancialresources,willingnesstoadoptnewtechnologies,prioritiesandindividualfarmcircumstances,andfutureplans.Intherightsetting,thesysteminstalledbyRobandLynneMcCartneycanbeaveryusefulupgrade.Technologiessuchasthese,whichmakeirrigationmoreefficientandeasierontheoperator,arelikelytobecomemoreprevalent.
What recommendations would you give to those thinking of installing such technologies?
Robhasfounditisessentialtoactuallycheckchannels,outlets,baysanddrainsregularly.Withthetelemetrysysteminplace,itiseasytojustassumealltheinfrastructureisingoodorder,wheninfacttherecouldbebankdecay,blockagesinthechannel,orleaksaroundthestops.Channelproblemssuchasthesealsohavethepotentialtoaffecttheirrigationschedulesrequired,astheautomationunitsdonotallowforchannelblowoutsorchangesinwatercommandlevels.
Any further comments?
TheMcCartney’sTaturafarmisnotyetpartofthemodernisedchannelnetwork.Thecoupleareinterestedtoseehowmuchmoreeffectivetheirautomationunitswillbeoncetheirsupplyismodernisedandtheyhaveamorereliablewatersupplylevelontotheirproperty.Eventually,thecouplewouldalsoliketolookintoinstallingsoilmoisturemonitoringprobesintheirirrigationbays,andhavethemtiedintotheautomaticirrigationunits.Thiscouldthenallowthemtomorecloselymatchirrigationstothewaterrequirementsoftheirirrigatedcrops.
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• FormoreinformationaboutIrrigationTechnologies,goto:www.dpi.vic.gov.au/dpi/vro/vrosite.nsf/pages/lwm_farmwater_irrigation_technologies
• Talktoanirrigationsurveyoranddesigneroroneofthecompaniesthatsuppliesandinstallsautomatedirrigationsystems
• CallDPIatEchuca(0354821922)orTatura(0358335700)andasktospeaktoanIrrigationModernisationOfficer.
• Talktootherfarmerswhohaveinstalledautomaticirrigationandtelemetrycontrolsystems
• Outletandtelemetrysystemcostsaretypicallyintherangeof$1,000–$1,800peroutlet,dependinguponthetypeofbayoutletandsystemsize.
FurtherinformationResearchTherehasbeenverylittleresearchintothewatersavingsbenefitsofautomatingborder-checkirrigation.Improvedlifestyleforthefarmers,andsavingsinlabourarelikelytobethemajorbenefitsintheGoulburnMurrayIrrigationDistrict(GMID).Unlikewater,whichvariesasacostofproductionfromyeartoyear,labourcostscanbeassumedtocontinuetoincreaseintothefuture,especiallyasskilledfarmlabourbecomesscarcer.
AdesktopstudybasedoninformationfromtwofarmsinnorthernVictoriareportedbyLavisetal.(2007)concludedthatborder-checkautomationwasassociatedwithreductionsinwateruseofbetween5%and9%,dependingonsoiltype.Thesavingsarosebecausewithautomation,irrigatorscouldcontinuetoirrigatebaysindividuallyandefficientlyatbusytimes,ratherthanadoptingthecommonpracticeofirrigatingseveralbaysatonceforlongerdurationatlowerflowrates,reducingtheirlabourinputbutleadingtodeepdrainageandwaterlosses.
Foragivenborder-checkirrigationlayout,thetwofactorsanirrigatorcancontrolaretherateandthedurationofwaterflowontotheirrigationbay.Bothaffectthequantityofwaterappliedtothebay.Ofthesetwocontrols,thedurationofirrigationistheeasiesttoadjust,butitsusehasmainlybeenbasedonexperienceratherthansciencetodate,becauseofarangeofissuessuchas:
• variableirrigationsupplylevels,andthereforevariableflowratesontofarmsandirrigationbays,whichcauseinconsistenciesforautomatedsystems.Modernisationoftheirrigationsupplysystempromisestogreatlyimprovetheconsistencyofirrigationflowratesandalleviatethisproblem.
• therequirementtoorderwater4daysaheadhasmeantthemoisturestatusofbaysatthetimeofirrigation,andthereforethecropwaterrequirement,couldbequitevariable.Again,systemmodernisationhaslargelyremovedthisasaproblem,withirrigatorsnowabletoorderandcancelwaterwithmuchlessnotice,meaningirrigationscannowbeappliedmoreconsistentlywithrespecttocropmoisturerequirement.
Modernisationshouldprovidemoreuniformoperatingconditionsthataremuchmoreconducivetoefficientsurfaceirrigationautomation.Inaddition,newmeteringwillprovidemoreaccuratemeasuresoftheactualflowrateandvolumeofwaterapplied.
Adoptionof‘highflow’irrigation,atflowratesabouttwicethelevelsofrecentbestpractice,willplacegreaterdemandsonirrigatorswithrespecttotimingofirrigationduration–mistakesathighflowrateswillbecorrespondinglygreater.Adoptionofautomation,asmadebyRobandLynne,willhelpensuretheycaptureanywatersavingbenefitsofhighflowrateirrigation.
Reference
Lavis,A.,Maskey,R.andLawler,D.(2007)QuantificationoftheFarmWaterSavingsWithAutomation,DepartmentofPrimaryIndustries,Victoria.
Background
ThisfarmhasbeenintheRyanfamilysince1865.AmajorchangetookplaceunderthepartnershipofJohnRyan’sfatheranduncle(WLandWLRyan)in1956whentheydecidedtodevelopaprivateirrigationdiversionfromLakeMulwalaontheMurrayRiver.Waterwasdeliveredtotheirpropertiesviaa16kmopen,earthenchannel.Soiltypesarepredominantlylightsandyclayloamswithhighinfiltrationrates,growingcereals,oatenhayandlucerne.
JohnandHeleneRyanboughtoutthepartnershipin1997.Their800hapropertythenhadawaterentitlementof1,171MLofhighsecuritywaterwhichtheenterpriseusedfully.TheRyan’shadalwaysknowntheir16kmsupplychannelwasinefficient,buttheproblemreallyhithomeduringthedroughtyearsof2006to2010whenseepage,leakageandevaporationlossesfromthesupplychannelconsumedmostoftheirreducedwaterallocations.
What change have you implemented and why did you do it?
Theoriginal16kmopenchannelsystemhasbeenreplacedwitha4.1kmpipelinepumpingdirectlyfromtheMurrayRiver.
UsingmethodsestablishedbyGoulburn-MurrayWaterandtheNorthernVictoriaIrrigationRenewalProjectforestimatinglossesinsimilaropenchannelsystems,theDepartmentofPrimaryIndustriescalculatedtheopenchannelsystemhadannuallossesof552MLduetoleakage,seepageandevaporation.Thenewpipelinesystemhasvirtuallyeliminatedthesewaterlossesfromthedeliverysystem,reducedlabourandon-goingmanagementcostsandwillenablediversificationofcroppingoptionsontheRyanfarm.
Where did you find information to help guide you?
Theprojecthadbeena‘pipedream’formorethanadecade,leftundevelopedduetothepotentialcost.JohnRyaneventuallydiscussedtheideawithDennisMoonfromCampaspeIrrigation,anirrigationdesignerandsupplier,whothendevelopeddesignoptionsandadvancedtheconcept.
InformationabouttheOn-FarmIrrigationEfficiencyProgram–whichhelpedfundtheproject–wasprovidedbytheDepartmentofPrimaryIndustries.TheOn-FarmIrrigationEfficiencyProgramisadministeredbytheGoulburnBrokenCatchmentManagementAuthority.
How much did it cost?
Thetotalcosttoremovetheoldsystemandinstallthepipelinewasapproximately$1.5million.About75%ofthiswasobtainedthroughtheAustralianGovernment’sOn-FarmIrrigationEfficiencyProgram,withtheRyansagreeingtotransfer276MLofwaterinordertoreceivefundingtoassistwiththeon-groundworksinvolved.
What was the result of the change and was the investment worthwhile?
TheRyanfamilybelievestheirenterprisewillbemoreproductiveandprofitableasaresultofinstallingthepipeline.Theyfeelthefarmisnowmoreviableandmoreresilienttothepotentialimpactsoffutureclimateandwaterpolicychallengesbecausetheycanusetheirwaterassetmoreefficiently.
TheRyansbelievecropyieldswerelowinthepastduetotheirinefficientirrigationdeliverysystem.Theybelievethenewsystemwillenablenew,highervaluecroppingoptions.What are the benefits?
Theprojecthasdeliveredarangeofbenefits.Waterlossesassociatedwiththeopenchannelsystemarenolongeranissue.Improvedwatermetering,installedaspartofthenewsystem,providestheabilitytoaccuratelymeasurethewateruseofindividualcrops.
Maintenancecostsofthepipelinearemuchlowercomparedwiththeopenchannel,withherbicidespraying,channelbankrepairsandde-siltingoftheopenchannelnolongerrequired.Landoccupiedbychannelscannowbereturnedtoproductivepurposes.
Thepressurisedwatersupplywillallowmoreprecisedeliveryofwaterwhenrequired,whichshouldleadtoimprovedcropyieldsandtheabilitytodiversifycrops.
Apressurisedsupplytothefarmalsopavesthewayforpossiblefutureprecisionirrigationdevelopment,basedonsprinklerordripirrigationtechnologies.
Who:TheRyanFamily
Where: Yarrawonga
Enterprise:Cropping
What:Oldchannelsystemreplacedbypipeline
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Overall,theRyanfamilyhaseveryconfidencethenewpipelinewilldeliverthedesiredresult.Thenewsystemwilldefinitelyprovideabetterirrigationsystem,ensuringthelongtermviabilityofthepropertyandincreasingitsvalue.Thenewsystemwillbeutilisedtogrowmoreprofitablecropsandallowmorediverseoptionstobeconsidered.
Are there any disadvantages?
Thepipelinehasahigherenergyusecomparedwiththeopenchannelsystem,whichisabusinessriskifenergycostscontinuetorise.TheRyansconsideredthetrade-offbetweenongoingpumpingcostsandthehigherinitialcostofinstallingalargerdiameterpipeoverthepipelinelength.Byinstallingalargerdiameterpipethantherecommendedminimumsize,theRyansreducedtheongoingenergycostofpumping,andtheimpactoffutureenergycostincreases.
Projectmanagementcosts,timetakenawayfromthecorecroppingbusinessandtheconsequentimpactontheRyan’slifestyle,wereissuesduringtheconstructionoftheproject.
Do you think other farmers would be interested in the change? Manypeople,includingneighbouringlandholders,havediscussedthesystemwiththeRyanfamilyandhavewatchedtheprogressoftheprojectoverthepast15months.
Are there situations where you think it wouldn’t work?
Replacinganeffectivelylinedchannelwithapipelinewouldhavelittlenetbenefit.Shortlengthsofopenchannel,lessthanonekilometre,areunlikelytowarrantconsiderationofapressurisedpipelineforwatersavingsalone.Situationswherelowercosttechnologycouldbeeffectivelyutilisedtosupplywatertothepropertywithminimallosses,inparticularwithgravitydelivery,maybepreferabletotheexpenseofpumpingthroughapipeline.
Is there anything else to add?
Thedecisiontoinstallalargerdiameterpipelinethantheminimumrecommended,toreducepumpingenergycosts,wasworthwhile.Thiswasatrade-offbetweenaninitialhighercost,largerdiameterpipeswithlowerongoingpumpingcosts,andlessexpensive,smallerdiameterpipeswithhigherongoingpumpingcosts.
TheprojecthasrequiredflexiblethinkingbyboththeRyansandtheircontractorstoachievethefinalresult.Theyrequiredagoodsolicitorwillingandabletodealwithsuchaproject,andneededtofindandusethebestpeopleavailableinotherareas.
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• Formoreinformationaboutirrigationtechnologies,goto:www.dpi.vic.gov.au/dpi/vro/vrosite.nsf/pages/lwm_farmwater_irrigation_technologies
• Talktoanirrigationsurveyoranddesigneroracompanythatsuppliesandinstallspipelinesystems.
Furtherinformation
ResearchIrrigationsupplychannellossesthroughouttheregionaccountforamajorproportionofallthewaterdivertedfromtheMurrayandGoulburnriversystems.Channelseepage,leakageandevaporationlossesestimatedforthelargeStuartMurraychannelsystemforthe2005/6seasontotalled31.5%ofentitlement(DSE,2010).Fortheprivate16kmlongchannelsystemthatpreviouslysuppliedtheRyan’sproperty,lossesduetoseepage,leakageandevaporationofabout50%arequiteunderstandable,consideringthepermeablesoiltypesanditssmallchannelsize.
PreventingsuchsignificantwaterlossesthroughpipingthesupplyclearlymakesalotofsensefortheRyans,whoduringthedroughtyearsmayhavepaidforalotofveryexpensivewaterthatdidnotendupontheircrops.
Formanyirrigatorsconsideringwhethertopipefarmchannels,thewatersavingsalonewouldnotjustifytheinstallationandongoingoperatingcostsofapipedsystem.Inthecontextofthewholefarmoperationhowever,wherewaterisonlyoneofmanyinputstothefarmingsystem,otheraspectsshouldbeconsideredinthedecision.Theseconsiderationsincludelabourandmaintenancecosts,flexibilityinfarmoperationsandlayout,increasedproduction,newcropoptions,andimprovedlifestylefortheoperators.
Thekeyistocarefullyconsiderthesedecisionsinthecontextofthewholefarmbusinessandthefarmingfamily’splansforthefuture.ToolsavailablethroughDPIsuchasWholeFarmPlanningcanhelpirrigatorsdecidewhattodointheirparticularcircumstances.
Reference
DSE,2010.WaterSavingsProtocolTechnicalManualfortheQuantificationofWaterSavings.DepartmentofSustainabilityandEnvironment
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Background
ColinMyerspurchasedhispropertyfromhisfatherintheearly1980s.Itconsistedofmarginallandwithlargeareasaffectedbysalinity.Overtheyears,thepropertyhasbeenusedforcropping,mixedgrazingandvegetablegrowing.Upuntil1990,thetraditionalcarryingcapacitywasaround1,000ewes(1,000DSE)on230hectares.Tosustainthiscarryingcapacity,mostoftheincomegeneratedfromthepropertywasgoingoutinirrigationwaterpumpingcosts(around80%).Thepropertywasnotonagravitysupplysystem,soallirrigationwaterhadtobeliftedfromtheLoddonRiver.Unreliableriverlevelsmadeirrigationsdifficult,withthepumpschangingflowastheriverleveldropped.Theenergycostsinvolvedwerehigh,andfloodsdamagedpumpsandmotorsseveraltimesinthe1980s.
What change have you implemented?
Thedecisiontodramaticallyreduceirrigationonthepropertyoccurredintheearly1990s.Basedonincreasingcosts,salinity,andotherdifficultiescombinedwithreducingcommodityprices,thedecisioncameeasily.Thedecisionresultedinthesellingofalargeproportionofthewaterentitlement.
Colinthenbecameinterestedintriallingnativegrassesonhispropertyduetotheirresiliencetodroughtconditionsandsalinity.Nativegrasseshaveanaturaltendencytoimprovegroundcover,suchanimportantaspectinfightingsalinityandwinderosion.
Why did you implement this change?
Throughoutthe1970sand1980sirrigationwasbecomingincreasinglyunprofitablefortheenterprise.Theirrigationwatersourcewasbecomingmoreunreliableintermsofallocationandquality,whilepumpingcostswereeverincreasing.Changingfromfullirrigationtomainlydrylandfarming,withintermittentirrigationwhenhighriverflowspermitted,isclosertonaturalrainfallevents.
Where did you find information to help guide you?
Wantingtoknowmoreabouthissoilsandnewmethodsfordealingwithsalinity,ColinjoinedthelocalLandcareGroup,wherehelearntwhathissoilsrequiredforoptimumhealthandthereforeperformanceinthelocalarea.Theaddedbenefitofthisknowledgewasreducedrelianceonchemicals,bothfertiliserandherbicide.
“Ifthesoilhastherightnutrientsinit,quiteoften
youwouldn’tneedtousesomanychemicals.So
westartedtolookatwhatthesoilsneedandfound
organicmatterwasthemainlackingingredient
(downto1%)andlowcalciumandhighmagnesium.”
Were you able to gain any assistance for the change?
Apartfromsomeassistanceinestablishingtallwheatgrass,therehavenotbeenanysourcesoffinancialassistanceavailabletoColinforthelongtermchangeshehasmade.ManyofthechangeshavebeenmadeonthebasisofspeakingtolocalDPItechnicalstaff,andasmanytechnicalpeopleaspossiblewhowereabletohelp.
“PeopleunderstoodwhereIwastryingtogettobut
wereunsureonhowtogetthereandbeviableatthe
sametime.”
OtherchangeshavebeentheresultofColintriallingdifferentapproachesandlearningfromhissuccessesandfailures.
Who:ColinMyers
Where: Kerang
Enterprise:Sheepandfatlambs
What:Transitioningtodrylandfarming
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What was the result of the change and was the investment worthwhile?
”Theextremelyhighdroughttoleranceofnative
grassesandshrubshelpstomakethefarmmuchmore
flexibleandresilient.Whilstwehadtomovetoa
muchlowerstockingrate,wealsodrasticallyreduced
alltheotherinputs;noirrigation,nofertilisers,no
spraysandmuchreducedlabour.Youmusttakethat
intoaccountwhenyoulookatourstockingrate.”
Colinhasn’tgonecompletelytonativegrasses,sostillreliesontheintroducedpasturespeciesonthepropertyforsomeproduction.Hesaystheamountofcloverandryegrassproductionisnowreallyimpressive.Colinsuspectsithassomethingtodowiththenativesprovidinggroundcover,andreducingsoilmoisturelossandwinderosion.
Althoughareductionincarryingcapacity(downtoapproximately400ewes),Colinnowsees80%ofincomegotohispocketratherthantocosts.Whilstirrigationisstillpossible(1996wasthelastevent),itisColin’sapproachtoflexiblefarmingandadaptationtochangingcircumstancesthatispayingdividends.
Why do you think the change has worked?
“We’veestablishedandencouragedanumberofnativespeciesonourproperty,includinghedgesaltbush,windmillgrass,speargrass,ratstailedcouch(growsinsalineareas),rubysaltbushandcreepingsaltbush.Allofthesearevitaltostopthelandfromdryingoutandcopingwiththesoilconditionswehad.”
Do you think other farmers would be interested in this change?
20yearsagothelandinpicture(below)wasbare,salinegroundthatwouldn’tgrowanything.Thisareahasstillneverbeenwateredexceptforflooding.Throughcarefulmanagementofstockingratesandlookingaftersoilhealth,thisareahasbeenturnedintoviable,productiveagriculturalland.
Colinsaysthewholepropertyisnowproductive,whichisremarkablegiventheconditionitwasin30yearsago.Thediversityofspeciesthatarenowpresentonthepropertyhasseeminglyincreasedthehealthofhisstock.AnexampleofthisisColin’sstockpreferencetograzespeciessuchasBeadbush,whichreplacestheneedforstocksaltlicks.
What recommendations would you give to those thinking of getting out of irrigation?
ThekeytothesuccessfulestablishmentandutilisationofnativegrassesandshrubsonColin’spropertyhasbeentocarefullymanagestockingratesandgrazing.Reducingstockingratestoasustainablelevel,aswellasthetimingofgrazingtoallowseedbankestablishmentandgermination,isvital.
Any further comments?
“I’mnowquitehappytohandthepropertyoverto
mychildrengiventhegoodsoilhealthandincreased
biodiversitynowpresent.”
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• Formanycasestudies,innovationsandtechnicalinformationaboutperennialsinprofitablefarmingsystems,seetheFutureFarmIndustriesCRCwebsite:www.futurefarmonline.com.au
• Forfurtherinformationonsoilhealth,seetheDPIVictoriaVictorianResourcesOnlinewebsite:www.dpi.vic.gov.au/dpi/vro/vrosite.nsf/pages/soilhealth_toolbox_managing_soil
Furtherinformation
ResearchColin’sexperienceindealingwitharangeofadversefarmingconditionsisagreatexampleofsomeoneadaptingtochange,andmakingpositivedecisionstotakebacksomecontrolovertheircircumstances.
Priortothedrought,thelandaroundKerangwasseverelyaffectedbysalinity.Whileirrigationonthebettersoilsonthepropertymayhavemaintainedproductivityonthoseareas,itislikelysalinityinthesurroundingareaswasalsomadeworse.
Colin’sdecisiontoreduceinputcostsalsochallengedtheconventionalfarmingbusinessmodelthatusuallyseekstoexpandorbecomemoreintensive.Whileclearlysuchdecisionswillnotsuitmany,thechoicesmadeareavalidoptionwhendealingwithchangesthatareforceduponthefarmenterprise.
Muchresearchandexperiencehasbeengainedinthepasttwodecadesintheimportanceofsoilhealth–especiallyhighorganiccontent,healthybiologicalactivityandplantselectionsthatsuitthesoil.Grazingmanagementalsoplaysaverybigpartinbuildingresilienceinthepastureplantsandsoilhealth,withstockingrates,durationandtimingallveryimportantinimprovingandmaintainingthehealthofthesoilandplants.
Withtheintroductionofwatermarkets,andmorerecentlybuybackprogramsforirrigationwater,manyfarmerswillbefacedwithhavingtomakedecisionsabouttheirfarmingfuture.ColinMyers’decisionstosellwateranddevelopalessintensivefarmbusinesshavegeneratedarangeofbenefitsforhim.Reducingdebtlevels,reducedlabourinput,improvedlifestyle,reducedenergyinputs,reducedherbicideusage,lowerfertiliserinputs,improveddroughtresilience,healthierstockandsoils,controloversalinity,andavailabilityofwatercreatedforotherusers–thesearesomeofmanypositivesresultingfromthechangesColinhasmadeinresponsetothechallengesthathavearisenoverthepast20years.
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Background
EdandMoiraBourke,alongwithsonDanandhiswifeCaitlin,farmapproximately1,500acres(over600hectares)atNathalia.Edhasbeenrunningthefamilyfarmsincetakingoverfromhisfathermorethan20yearsago,andheandMoirahavenowbeenjoinedbyDanandCaitlininthefamilyfarmingoperation.
Theyrun900firstcrossewesand55beefcattleaswellascroppingwheat,barleyandoatsonthepropertywhichcomprisesmainlysandyloam/loamsoiltypes.
ThepropertyisirrigatedviaanelectricpumpsiteddirectlyontheBrokenCreek(ontheMurraysystem)aswellasanumberofoutletsservicedbytheSheppartonchannelsystem.
What change have you implemented?
Originally,thepropertywaslaidoutforfloodirrigation.In2009theBourkeshadaWholeFarmPlanpreparedfortheproperty.OneofthereasonsfordevelopingtheWholeFarmPlanwasthefact40hectaresonthehomepropertyideallylentitselftoacentrepivot.Itwasagoodsizedsectionofland,hadsandysoilsandtheirrigationinfrastructureneededupgrading.
Thecentrepivotwasinstalledtwoyearsago.TheBourkescouldn’tspeakhighlyenoughoftheexcellentservicetheyreceivedbeforeandduringtheinstallation.
“Theywereveryhelpfulansweringquestionsand
explainingthingsclearlysotherewerenoconcerns
astowhetherweweredoingtherightthing.”
Whiletheyhadn’teverirrigatedusingacentrepivotbefore,theBourkeswereconfidentitwouldbesuitabletechnologyforthispartoftheirproperty.OtherthanspeakingtothePlanrightirrigationdesignerandthestafffromRichRiverIrrigation,theydidn’tactivelysearchforinformationbeforemakingthedecisiontoinstallthecentrepivotontheirproperty.
Why did you implement this change?
TheBourkessaidtherewereanumberofreasonsforwantingtoinstallthecentrepivot.Whiletheattractionofimprovingthewateruseefficiencyonthatsectionofpropertyfeaturedhighly,therewerealsotheaddedbenefitsofupgradingtheirrigationinfrastructure,lifestylebenefitsinreducingthetimeinvolvedinwatering,aswellasprovidingadditionalcropproductionoptions.
The40hectareslentitselfperfectlytoacentrepivot;ithadsandysoil,wasagoodsizedarea,locatedclosetotheBrokenCreekandhadnonativevegetationimpacts.
Who:Moira,EdandDanBourke
Where: Nathalia
Enterprise:Sheep,BeefandCropping
What:Conversionoffloodtosprayirrigation
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What did it cost to make the change?
TheBourkesestimateitcostaround$200,000toinstallthecentrepivotandassociatedstructures.Theactualpivotcostcloseto$185,000andanother$20,000wasrequiredtoupgradethetransformerfortheelectricpump.
Therewasverylittleworkrequiredtodecommissiontheoldfloodirrigationsetup.Onefenceneededtoberemoved,farmchannelsfilledinandbayoutletspulledout.Veryminimalearthworkswererequired.
TheBourkesfundedtheentireprojectthemselvesasnootherfundingopportunitieswereavailableatthetime.
What was the result of the change?
Oneofthemostnoticeablechangessincetheinstallationofthecentrepivothasbeenthereductioninwaterusage.Toirrigatethe40hectarespreviously,theywoulduse20MLperirrigation.Withthecentrepivot,thishasbeenreducedto7.5MLperwatering*.Theuniformityofirrigationhasalsobeenapositiveoutcome,withtheBourkesnotingthereisnowamuchmoreevendistributionacrosstheirrigatedarea.
Anotherbigplushasbeentheabilitytosowgrazingwheattoprovidefeedfortheewesandlambsoverwinter,autumnandearlyspring.Whenitwasfloodirrigated,thisoptionwasn’tpractical,especiallyduringthedryyears.TheBourkessaythecentrepivothasledtoanincreaseintheproductivityofthe40hectareswhichwaspreviouslyjustusedasagrazingpaddock.Whilenotabletoquoteexactfigures,theyfirmlybelieveithasimprovedthetonnageperhectareproducedfromthatarea.
Theyalsohighlightthatwateringisaloteasiernow,withmoretimeavailabletodootherthings.
“Becauseitisanautomatedsystem,there’snoneed
tobeupatnightchasingwater.Itdefinitelysaves
time.”
TheonlynegativefromtheBourkes’perspectivewasthefacttheyhadtopaythefullcostofupgradingthepower-supplytransformerforthepump.However,insayingthis,theydidnotetheassistancetheyreceivedfromPowercorduringthistimewasmuchappreciated,astheymadetheprocesseasierbykeepingtheBourkesinformedandup-to-dateduringtheupgrade.
Was the investment worthwhile?
TheBourkescommentedtheydidn’trealisehowmuchwatertheywouldsavebeforetheybeganirrigatingwiththecentrepivot.Theyknewtherewouldbewatersavings,buthadn’treallycrunchedthenumbers.
Althoughnotabletoaccessanyfundingassistancetoinstallthecentrepivot,thefamilybelievesitisthebestthingtheyhavedonetoimprovetheirfarm.Havingtheabilitytoproduceautumnandspringfeedfortheirewesandlambsisahugebenefittotheirfarmingoperations.
Giventheywerepreviouslypumpingwaterontotheproperty,thehigherpumpingcostsforthecentrepivotwasn’tmuchofanissueforthem.TheBourkesareawareitonlytakes36hourstodoafullcycleofwatering,andthiscanbedoneontheweekendwhentheycanuseoff-peakelectricity.Theusageofoff-peakelectricityalongwithshorterpumpingtimeshasgreatlyreducedtheamountofelectricityused,andsoreducedtheoperatingcost.
Itmighthavebeenadifferentstoryiftheirpreviousirrigationsystemhadbeengravityfed,buttheirsoiltypes,locationonthefarm,existinglayoutonthe40hectaresandtheirneedforbetterwaterusage,meantthecentrepivotwouldprobablystillhavebeentheirpreferredoption.
Would other farmers be interested in the change? TheBourkescommentedthatotherfarmersintheareahavealreadyvisitedtheirpropertytolookatthesetupanddiscussthedifferenceithasmadetotheBourkes’productivityandfarmingoperation.Whilesomeofthesevisitsarepurelyoutofcuriosityaboutthenewtechnology,theysayanumberofvisitorsarepeoplegenuinelyinterestedinthepotentialofacentrepivotfortheirownproperties.
Are pivots for everybody?
TheBourkesnotethateverysituationisdifferentandacentrepivotmightnotbetheanswerforallproperties.TheybelievetheirWholeFarmPlanwasusefulinidentifyingthepotentialforacentrepivotonthatparticularpartoftheirproperty.Ifthesoiltypeshadbeenheavier,thegravityfloodinfrastructurebeenmodernisedornativevegetationprevalent,acentrepivotwouldnothavebeenthemostappropriatetechnologytoinstall.Individualsshouldtakeintoaccounttheirowncircumstancesbeforemakingsuchadecision.Apotentialuserneedstounderstandwhattheywanttoachieveandwhatthecostisgoingtobe.FortheBourkes,thefuturebenefitsofthecentrepivotfaroutweighedtheinitialcostofinstallation.
* Beawaretotalwateruseshouldbeassessednotjustperirrigation
11Stateoftheart-onirrigationfarms-Edition2
Formoreinformationaboutirrigationtechnologies,goto:
• www.dpi.vic.gov.au/dpi/vro/vrosite.nsf/pages/lwm_farmwater_efficient_irrigation_design_4.2
• DPIAgNote#AG1280.CentrePivotSystemCapacity.Published:June2007
• DPIAgNote#AG1281CentrePivots–CapitalandOperatingCostTrade-off.Published:June2007
• Talktoanirrigationsurveyoranddesigneroracompanythatsuppliesandinstallstravellingirrigationsystems.
• CallDPIatEchuca(0354821922)orTatura(0358335700)andasktospeaktoanIrrigationModernisationOfficer.
• Talktootherfarmerswhohaveinstalledcentrepivotorlateralmoveirrigators.
Furtherinformation
ResearchCentrePivotirrigatorsprovideprecisecontroloverirrigationapplicationratesandareparticularlywellsuitedtoirrigatinglightersoils.IntheBourkes’particularsituation,thefacttheyalreadypumpedwaterfromtheBrokenCreektosupplyaninefficientborder-check(flood)irrigationlayout,madeacentrepivotsystemagoodoption.Installingacentrepivotsystemmeanttheyavoidedlasergradingcosts,andbypumpinglessvolumeofwater(7.5MLperirrigationcomparedto20ML,albeitatahigherpressure),hasalsohelpedtocontainthepumpingcost.
AcomprehensiveguideforanyoneconsideringwhethertoinstallacentrepivotorlateralmoveirrigatorcanbefoundontheDPIwebsiteattheaddressgivenbelow.
Thekeypointstonoteareasfollows:
• Afarmwatersupplysystemneedstobeabletosupplythevolumeofwaterrequiredondemand.Thisisgenerallymoredifficultintheun-modernisedchannelnetworkreliantuponmanualdeliveries,especiallyonsmallerchannels.
• Correctsizingofthesystemneedstotakeintoaccountanumberofissues,butthemainlimitisthesystemcapacity,whichisthemaximumamountofwateritcanapply.Mostsystemsaretypicallyratedbetween8to20mm/day.Ifasystemisundersized,thenitwillbeunabletoapplyenoughwatertomeetcropwaterrequirementsduringthehottertimesoftheyear.Thismaycompromisemaximumproductiononoccasionsinsummer,butontheotherhand,asmallersystemwillhavealowerpurchasecostandoperatingcostswillalsobereduced.
• Havingalowersystemcapacitydoesnotnecessarilymeanplantswilldieinhotweather.Whileoperatingalowercapacitysystemcontinuouslycanmaintainsoilmoisturelevels,ifthesystemcapacityislowerthanthepeakwaterrequirement,thecropwillextractwaterfromthesoilfasterthanthepivotcanreplaceit.Ifthepivotthenbreaksdown,itcanbeverydifficulttorestoresoilmoisturelevelsforoptimalproduction.Asmallersystemcapacityrequiresahigherlevelofmanagementtoavoidproductivitylossandisatgreaterriskofcroplossesifthereisabreakdownorpoweroutage.Alargersystemcapacitygivesadditionalsecurityforlimitedadditionalcapitalcost.
TheDPIAgNote1281(CentrePivots–CapitalandOperatingCostTrade-off)describesindetailthetrade-offbetweenupfrontcapitalcostsandoperatingcosts.Aslightlyhighercapitalinvestmentup-frontcanreduceoperatingcostsoverthelifeofthesystem.Cheaper,smallersizedsystemscostmoretorun,soitisimportanttoweighupallaspectsofdesignandoperation.Selectingalargersystemcapacitynotonlyimprovessecurity,butoperatingcostsarealsolowered,contributingtowardsbottom-linefarmprofitability.
BaseduponthehistoricalclimatedataforTatura,theminimumrecommendedsystemcapacityis12mm/day.Toachieveanirrigationof20to25mm,afullcirclewouldneedtobesettooccurovertwodays.Stageofcropgrowth,timeofyearandrainfallalsoneedtobetakenintoconsiderationwhendecidingwhentoscheduleirrigations,butcanusuallybeeasilyprogrammedandhandledbymoderncentrepivotcontrolsystems.
Themajorrunningcostsofpressurisedirrigationsystemsaredirectlyrelatedtopumping.Typicalenergyrequirementsare130kWh/MLpumped,soatapeakelectricitychargeof28c/kWh,thecostis
$36/ML.Ifoff-peakpowercanbeused,thecostwillbeabouthalf.Dieseloperatedpumpingwilltypicallyrequire39litresofdieselperMLapplied.ThereforeintheBourkes’system,eachirrigationwillusenearly1,000kWhofelectricity,andcostapproximately$120to$270,dependingupontheelectricitypricetariffandsupplycharge.
12 Stateoftheart-onirrigationfarms-Edition2
Background
BarryandDonnastartedoutfarmingasirrigators.Intheearly1990sthecostofwaterwasreachingapointwheretheyfeltitwasbecomingunviabletokeepirrigating,sotheybeganaprocessoftransitioningintodrylandagriculture.Thedecisiontoexpandintodrylandagriculturewasreinforcedbythedroughtconditionsinrecentyears.
Becauseofthedryconditions,thelastirrigationoccurred4yearsago.Althoughwaterbecameavailableagainin2010,itwascarriedovertothisyear.Itwillbeusedtoirrigatelucernetofinishtheprimelambs,whichwastheprimaryuseofirrigationbeforethedrought.
Theirpropertyisnow1,740hainarea;ofwhich32haisstillabletobeirrigatedwiththe40MLwaterrightstillremaining.
What have you changed?
PurchasingirrigationpropertiesandusingthemfordrylandagriculturehasrequiredDonnaandBarrytomakeanumberofchangestothefarms.Thishasincludedearthworksandfencing,filling-intheirrigationchannelsandpullingoutthechannelstops,aswellasensuringinfrastructureisavailableforthestockanddomesticwatersupply–whichinvolvedinstallingpipesandtroughs,andinonecaseconnectingtotheirrigationbackbone.
Thesechangescanbecostly.Asanexample,one324hectaredairypropertypurchasedbythecouplerequired$45,000worthofcontractorworkforearthworks.Barryworkedfor2monthssolidpreparingtheareafordrylandcropping,includingpullingoutchannelstopsandremoving12kmoffencing.OtherpropertiestheyhavepurchasedhaverequiredaboutamonthofBarry’slabour.
Thesechangesmaximisetheefficiencyoffuturecroppingpracticesbyexpandingtheareaofeachpaddocktoasizethatisoptimumforcroppingmachinery.
Ongoingcostsarealsoassociatedwithtransitioningirrigationpaddocksintodrylandpaddocks.Soilsinareaswherechannelshavebeenremovedhaveatendencytoslumpovertime.Theserequiretoppingup2yearsaftertheinitialworkisdoneandthenagain3-4yearslater.Inthepast,thishasrequiredabout2weeksofBarry’slabour.
Preparingirrigationlandfordrylandagricultureisgenerallyasmoothprocessthattakesabout6months.However,discussionswiththerelevantorganisationstodisconnectpropertiesfromthesystemcanbelengthy.
What made you decide to expand into dryland farming?
Thedecisiontoexpandtheareaofdrylandagricultureandreduceirrigationhasbeentheresultoflowwateravailabilityandhighwaterpricesmakingdrylandfarmingmoreviablethanirrigation.
ThedecisiontoincreasetheirareaofdrylandfarmhasbeenrelativelyeasyforBarryandDonna,asithashappenedgraduallyovermanyyears.Theybelieveitisimportanttobecontinuallyadaptingtochangingconditions.
“Droughttaughtushowtofarmwithoutwater.So
nowwearefarmingmoreMalleestyle.These
changescanbehardfortheoldergeneration.”
What made you decide to expand into dryland farming?
ThechannelsupplyingtheremainingirrigationonthepropertyiscurrentlyopenanddiscussionstodecommissionthischannelaspartoftheNorthernVictoriaIrrigationRenewalProject(NVIRP)willoccurinthefuture.Decommissioningthechannelwillprovidebothchallengesandopportunities.
Forexample,thechannelwaterisusedforstockanddomesticsupplyandprovidesabarrierforsheepinsomepaddocks.Therefore,infrastructuretocontinuethesupplyofstockanddomesticwaterwillbeneededandadditionalfencingmayberequiredinsomepaddockswherechannelsareremoved.Compensationwillbeneededfortheassociatedcosts.
“It’simportanttorememberfilling-inchannelsalso
resultsinfilling-inofdrainagesystemsthatare
importantwhensalinityispresent.”
Who:BarryandDonnaSmith
Where: LoddonValleyirrigationarea
Enterprise:Croppingandgrazing
What:Irrigationpropertiespurchasedandconvertedtoonemixeddrylandfarm
Stateoftheart-onirrigationfarms
AGradualTransitiontoDryland
Onthefarm
13Stateoftheart-onirrigationfarms-Edition2
Onthepositiveside,decommissioningtheirrigationchannelcouldprovideanopportunitytochangethelayoutofthelandtomaximiseefficiency,forexample,establishinglargerpaddocksforcroppingandaddingpotentialvegetationbufferstrips.
Ifthechannelisdecommissioned,BarryandDonnawillexpandtheircurrentdrylandcroppingintotheremainingirrigationpaddocks.Thiswillbearelativelyeasytransition.
Have you been able to find good information?
DonnaandBarryarepredominantlydrylandfarmersandwillonlyrequirelimitednewinformationtofurtherexpandtheiroperation.However,theyrecognisegainingknowledgeisanimportantfirststepforthosewhohaven’tbeeninvolvedindrylandfarmingbefore.
Understandingthesoilcapabilityofafarmandtheexpectedreturnsfromdistrictaveragesisimportant,especiallyasreturnscanvarygreatlyfromdistricttodistrict.DonnaandBarryalsobelieveit’simportanttouselocalfarmnetworkstoaccesslocalknowledge.
Moderntractorsandheadersgenerallyhavealotoftechnologyassociatedwiththem,soundertakingtrainingsessionsonthisequipment,asBarryhasdone,canbeveryuseful.
“Peopledoneedsometrainingandeducationtoget
uptospeed.Thereisalotofinformationaround.”
How does the switch to dryland farming change profitability?
BarryandDonnapredominantlydrylandcrop.Thetransitiontotheircurrentpositionhasinvolvedpurchasingirrigationblocksandsellingthehighreliabilityirrigationwatertofundthepurchase.Thisensuredthecouplecontinuedtoincreasetheirequitywhileexpanding.
Theprofitabilityofbothdrylandgrazingandcroppingisgenerallylow,thereforethecouplehaveincreasedthesizeoftheirlandholdingtoensuretheirbusinessgeneratesalargeenoughreturntosupporttheirlifestyle.
Awheatcropreadytobeharvested
Theirrigationchannel
Sheepgrazeinalucernepaddock
Oneoftheremainingpaddocksthatcanbeirrigated
14 Stateoftheart-onirrigationfarms-Edition2
Ifyouwouldliketoreceivethisinformation/publicationinanaccessibleformat(suchaslargeprintoraudio)pleasecalltheCustomerServiceCentreon136186,TTY1800122969,oremailcustomer.service@dpi.vic.gov.au.PublishedbytheDepartmentofPrimaryIndustriesFarmServicesVictoria,May2012.
©TheStateofVictoria2012.
Thispublicationiscopyright.NopartmaybereproducedbyanyprocessexceptinaccordancewiththeprovisionsoftheCopyright Act 1968.
AuthorisedbytheDepartmentofPrimaryIndustries,1SpringStreet,Melbourne3000.
ISBN978-1-74326-108-8(print)ISBN978-1-74326-109-5(online)
Disclaimer ThispublicationmaybeofassistancetoyoubuttheStateofVictoriaanditsemployeesdonotguaranteethatthepublicationiswithoutflawofanykindoriswhollyappropriateforyourparticularpurposesandthereforedisclaimsallliabilityforanyerror,lossorotherconsequencewhichmayarisefromyourelyingonanyinformationinthispublication.
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www.dpi.vic.gov.au
http://vro.dpi.vic.gov.au/dpi/vro/vrosite.nsf/pages/lwm_state_art_irrigation
AdoptingSustainableFarmingPractices
Formoreinformationaboutpostirrigationoptions:
• CallDPIatEchuca(0354821922)orTatura(0358335700)andasktospeaktoanIrrigationModernisationOfficer.
• Talktootherfarmersinyourdistrictwhohavemadetransitionsawayfromirrigation.
Furtherinformation
ResearchTheimpactofthedrought,watertrade,unbundlingwaterfromlandandchannelrationalisationonirrigationfarmingintheGoulburn,MurrayandLoddonirrigationdistrictsoverthepast10yearshasbeenenormous.Mappingofirrigatedland-usechangeacrosstheregionfrom2003to2008hasrecordedadropinperennialpasturefrom141,000hato35,000ha.Autumnpasture/crophasdroppedfrom73,000hato32,000ha(DPI2010).Overallirrigationactivityreduced40%andperennialpasturereduced75%.Thisfollowsontopofchangesmappedbetween1996and2003,whentheareaofperennialpasturefellfrom203,000to141,000ha.(Morse-McNabbetal2008.)
ForlandholdersliketheSmithswhowishedtoremainfarmingwhilstadaptingtothechangesgoingonintheregion,theirdecisiontotradewaterforlandareaisareflectionoftheregionalfigures.BarryandDonnaclearlyrecognisetheprofitabilityofdrylandfarmingissubstantiallylowerthanirrigationfarming.AustralianBureauofStatisticsfigures(ABS2006)foundfarmsthatirrigated,generatedonaverage55%moreoutputperfarmin2003–04thanfarmswhichdidnotirrigate,hencetheneedtoincreasefarmareatomaintainenterprisescaleandprofitability.
WhiletheSmithsmayyetenduphavingtheirlastremainingirrigationsupplydecommissioned,foranyfarmenterprise,keepingitopenasanoptionprovidesadditionalsecurityandresiliencetotheenterprise.Particularlygiventheuncertaintyofdroughtandthefailureoftimelyrainsinsomeyears,theabilitytomaintainlucerneproductionduringadryphase,ortobeabletofinishoffaspringcropiftherainsfail,ispotentiallybeneficial.Especiallyinseasonswithhighwateravailability,temporarytradeofwaterwillbecheap,soretainingtheabilitytocapitaliseonsuchopportunitiesmaybevaluableformanyfarmenterprises,aswellasfortheregionalcommunityandeconomy.
Reference
McAllisterA,2010.UnderstandingLandholders:ChangingLanduseintheGMID.MilestoneReport,DPI.
Morse-McNabbL,McAllisterA,KaineG,RowbottomBandLinehanC.2008.SpatialmarketsegmentationandHealthproductivelandscapeframework.DPIreport.ISBN978-1-74199-971-6
ABS,2006.CharacteristicsofAustralia’sIrrigatedFarms2000-01to2003-04,#4623.0,ISSN0642482241
