In October 2013 construction of the New Parallel Runway (NPR) progressed to its next important stage – the Dredging and Reclamation works. Sand pumping was completed on 7 December 2014.
The DReDge VeSSel
• BrisbaneAirportCorporation(BAC)signedacontractwithJandeNul(Australia)PtyLtdinOctober2013,oneoftheworld’slargestandmostexperienceddredgingcontractors,toundertakethereclamationworksatthe360haNewParallelRunwaysiteatBrisbane Airport.
• JandeNulusedtheCharlesDarwintrailersuctionhopperdredge(TSHD),oneofthenewestinitsfleet,toundertaketheworks.
• TheCharlesDarwinusedpowerfulsuctiontubesequippedwithadragheadtodrawsandfromanapprovedsiteinMoretonBayintoits‘hopper’fortransportashore.
• OnceatitsmooringtheCharlesDarwinpumpedamixtureofsandandwaterthrougha4.5kilometrelongpipelinetothereclamation site.
• Thesiterequired11millioncubicmetresofsandtoraiseitabovetheone-in-100-yearfloodlevel.
Thepreparatoryworksincludedconstruction of:
• AtemporarydredgemooringintheBrisbane River;
• ApipelinetotherunwaysitecrossingtheLuggagePointWasteWaterTreatmentPlantlandandtheoperationalairfieldatBrisbane Airport;
• Theprimaryreclamationbund;and
• BMD,theCivilWorkscontractor,tocompletethesiteclearing.
The ReclamaTION
• Theareafilledisapproximately360ha-3600mlongandabout1000mwideandcurrentlysitsataroundsealevel.
• Thegroundlevelmustberaisedby3mfortheNPRtobefloodproofandimmunefromrisingsealevelsbroughtaboutbyclimatechange.
• Italsorequiresraisingtointegrateseamlesslywiththeexistingrunwayandtaxiwaysystem.
• TheunderlyingsoilsoftheNPRsiteareverysoftandextendto35mbelowground surface.
• Theapplicationofaheavyload(eg:sand)forcesmoistureoutofthesoilcausingthegroundleveltosinkastheearthisconsolidatedtoformastablefoundationfortherunway.Thisisknownas‘settlement’.Partsofthesitewillsinkbymorethan2m.
PROJecT UPDaTeMARCH2015
1.TheJandeNuldredge‘CharlesDarwin’completeditstaskofpumping11millioncubicmetresofsandashoretothereclamationsitenearlytwomonthsaheadofscheduleon7 December2014.
OVeRVIeW
ThisFactSheetprovidesinformationabouttheextensiveenvironmentalstudiesundertakenandtheenvironmentalmanagementwhichwasputinplacetomonitortheDredgingandReclamationworksforBrisbaneAirportCorporation’sNewParallelRunway(NPR)project.
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NEW PARALLEL RUNWAY
DReDgINg&ReCLAMATIONWORkS
about Brisbane airport: BrisbaneAirport(BNe),isthepremiergatewaytoQueenslandandthethirdlargestairportinAustraliabypassengernumbers.Operating24hoursaday,sevendaysaweek,BNehastwomajorterminalsservicing28airlinesflyingto41nationaland27internationaldestinations.Morethan22millionpassengerstravelledthroughtheairportin2014.BNewasnamedCapitalCityAirportoftheYearinthe2014AustralianAirportsAssociationNationalAwardsandratedasAustralia’sNo.1airportforqualityofservice10yearsinarowintheAustralianCompetitionandConsumerCommissions’annualsurvey.
Forinformationvisitwww.bne.com.auoremailinfo@bacmajorprojects.com.au
• geotechnicalinvestigationshaverevealedthatthesoilsvaryinstrengthovertheNPRfootprint.Sandwasstrategicallyplacedatvaryingheights,uptoamaximumof8mabovegroundleveloverthesoftestareas,toachieveasuitablyuniformgroundsettlementalongits3600mlength.
• geotechnicalmodellinghascalculatedthattoraisethesurfacelevelby3mandachievethenecessarysettlementwithinfouryears,upto11millioncubicmetresofsandwouldbe required.
• Toacceleratethesettlementprocess,330,000vertical‘wickdrains’wereinsertedintothegrounddownto35metresinthesoftestpartsofthesite.Thisallowedthemoisturetobedrawnfromthesoilmorequicklythanbytheactionofgravityalone.
• Thereclamationdesigninvolvedmorethan10,000kmofthesewickdrainsbeingspacedascloseasonemetreapartinthesoftest areas.
environmental management
• ThedredgingwascarriedoutwithinanareaadjacenttothemainshippingchannelinMoretonBay.
• BAChadafederallyapprovedConstructionenvironmentalManagementPlan(CeMP)inplacetomanageanyimpactsasidentifiedintheenvironmentalImpactStatementandMajorDevelopmentPlan(eIS/MDP)process.Referto:www.bne.com.au/corporate/upgrading-your-airport/new-parallel-runway/eismdp
• BACanditscontractorJandeNulhaddedicatedprofessionalenvironmentteamsinplacetoimplementtheapprovedCeMPandoverseearangeofsuccessfullyprovenenvironmentalmanagementstrategiesforbothonandoffairportland.
• Themostsignificantenvironmentalissuesincludedmonitoringofwaterqualityandbiodiversitybothonandoffairport.
• A24/7real-timemonitoringprogramwasinplaceoncethedredgecommencedworktoensureallwaterqualitylimitsweremetthroughoutthecourseoftheworks.
• Aprevioustrialdredgingin2008conductedattheNPRdredgesitedemonstratedthatnoharmfuleffectsoccurredintheenvironmentallysensitiveareaseithersideoftheextractionfootprint.
• Thesandwaspumpedtothesitethroughthepipelineinaslurrymixofwaterandsandinaratioofupto5:1.
• Thatmeansforeachloadof30,000m3ofsand,upto150,000m3ofwaterwasalsodeliveredtothereclamationsiteformanagementpriortorelease.
• ThewaterwastakenfromtheBrisbaneRiveratthemooringlocationandmixedwiththesandforpumpingpurposes.
• Thewaterwascontainedonsitewithintheprimaryreclamationbundandtail-waterpondsallowinganysedimenttosettleoutbeforebeingreleasedbackintothesystemviathenewmajordrainagechannelsconstructedaspartofearlycivilworks.
• Waterwasnotreleaseduntilestablishedwaterqualitydischargelimitsweremet.
• Dredgingandsandpumpingoperationswerecompletedon7December2014.
• Thesitewillnowbeallowedtosettleforfouryearstoprovideacompressedandstablebaseonwhichtobuild.
• TheNewParallelRunwayisscheduledtobecommissionedby2020.
2.Thewaterandsandmix(ratioof5:1)arrivesonsitefromthedredgesite.
3.Wickdrainswerepunchedintothesoftunderlyingsoildtoadepthofover30metrestohelpdrainthesite.
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Forinformationvisitwww.bne.com.auoremail:[email protected]