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  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <import namespace="http://xbrl.sec.gov/invest/2012-01-31" schemaLocation="http://xbrl.sec.gov/invest/2012/invest-2012-01-31.xsd" />
  <import namespace="http://www.xbrl.org/2009/role/net" schemaLocation="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd" />
  <import namespace="http://fasb.org/us-gaap/2012-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd" />
  <element id="gldd_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="gldd_EquipmentRelatedCostsPercentageOfCostsOfContractRevenue" name="EquipmentRelatedCostsPercentageOfCostsOfContractRevenue" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_DredgingMember" name="DredgingMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_DemolitionMember" name="DemolitionMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_ComponentsOfContractsInProgressTableTextBlock" name="ComponentsOfContractsInProgressTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_ContractReceivableTypeAxis" name="ContractReceivableTypeAxis" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" xbrli:periodType="duration" />
  <element id="gldd_ContractReceivableTypeDomain" name="ContractReceivableTypeDomain" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_CompletedContractsMember" name="CompletedContractsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_ContractsInProgressMember" name="ContractsInProgressMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_AccountsReceivableNoncurrentAndContractReceivableRetainage" name="AccountsReceivableNoncurrentAndContractReceivableRetainage" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="gldd_FuelHedgeContractsMember" name="FuelHedgeContractsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_PercentageOfCompletionAdjustment" name="PercentageOfCompletionAdjustment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="gldd_BidsBondRange" name="BidsBondRange" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="gldd_OutstandingPerformanceBonds" name="OutstandingPerformanceBonds" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="gldd_RevenueValueRemainingFromOutstandingPerformanceBonds" name="RevenueValueRemainingFromOutstandingPerformanceBonds" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="gldd_CapitalContributions" name="CapitalContributions" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="gldd_LineOfCreditFacilityOptionalIncreaseCapacity" name="LineOfCreditFacilityOptionalIncreaseCapacity" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="gldd_MulticurrencyMember" name="MulticurrencyMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_SwinglineLoansMember" name="SwinglineLoansMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_ScheduleOfCondensedConsolidatingOperationsAndComprehensiveIncomeTableTextBlock" name="ScheduleOfCondensedConsolidatingOperationsAndComprehensiveIncomeTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_DistributionsPaidToNoncontrollingInterests" name="DistributionsPaidToNoncontrollingInterests" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="gldd_IncomeLossFromEquityInvestmentsInSubsidiaries" name="IncomeLossFromEquityInvestmentsInSubsidiaries" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="gldd_IncreaseDecreaseInCostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear" name="IncreaseDecreaseInCostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="gldd_IncreaseDecreaseInBillingsInExcessOfCost" name="IncreaseDecreaseInBillingsInExcessOfCost" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="gldd_InvestmentsInSubsidiaries" name="InvestmentsInSubsidiaries" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="gldd_PaymentsForProceedsFromAccountsWithAffiliates" name="PaymentsForProceedsFromAccountsWithAffiliates" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="gldd_PaymentsOfDividendsShareBasedCompensation" name="PaymentsOfDividendsShareBasedCompensation" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="gldd_InterestRateTypesAxis" name="InterestRateTypesAxis" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" xbrli:periodType="duration" />
  <element id="gldd_InterestRateTypesDomain" name="InterestRateTypesDomain" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_BaseRateMember" name="BaseRateMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_LiborRateMember" name="LiborRateMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_CostsAndEarningsForContractsInProgress" name="CostsAndEarningsForContractsInProgress" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="gldd_BillingsForContractsInProgress" name="BillingsForContractsInProgress" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="gldd_CostsAndEarningsInExcessOfBillingsForCompletedContracts" name="CostsAndEarningsInExcessOfBillingsForCompletedContracts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="gldd_CostsAndEarningsInExcessOfBillingsForContractsInProgress" name="CostsAndEarningsInExcessOfBillingsForContractsInProgress" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="gldd_BillingsInExcessOfCostsAndEarningsMember" name="BillingsInExcessOfCostsAndEarningsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_DerivativeUnderlyingHedgePercent" name="DerivativeUnderlyingHedgePercent" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <element id="gldd_GainLossOnAdjustmentOfContingentEarnout" name="GainLossOnAdjustmentOfContingentEarnout" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="gldd_CostsAndEarningsInExcessOfBillingsMember" name="CostsAndEarningsInExcessOfBillingsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_TotalLeverageRatio" name="TotalLeverageRatio" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_DredgingSegmentMember" name="DredgingSegmentMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_DemolitionSegmentMember" name="DemolitionSegmentMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_NatureOfBusinessAndSummaryOfSignificantAccountingPoliciesTable" name="NatureOfBusinessAndSummaryOfSignificantAccountingPoliciesTable" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" xbrli:periodType="duration" />
  <element id="gldd_NatureOfBusinessAndSummaryOfSignificantAccountingPoliciesLineItems" name="NatureOfBusinessAndSummaryOfSignificantAccountingPoliciesLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="gldd_PercentageOfDebtInstrumentIssuedAtFaceValue" name="PercentageOfDebtInstrumentIssuedAtFaceValue" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_ForeignMember" name="ForeignMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAociOnDerivativesNetOfTax" name="OtherComprehensiveIncomeLossReclassificationAdjustmentFromAociOnDerivativesNetOfTax" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="gldd_FairValueMeasurementsGoodwillUnobservableInputReconciliationTableTextBlock" name="FairValueMeasurementsGoodwillUnobservableInputReconciliationTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_ChangesInComponentsOfAccumulatedOtherComprehensiveIncomeTableTextBlock" name="ChangesInComponentsOfAccumulatedOtherComprehensiveIncomeTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_AdjustmentsReclassifiedFromAccumulatedOtherComprehensiveIncomeToEarningsTableTextBlock" name="AdjustmentsReclassifiedFromAccumulatedOtherComprehensiveIncomeToEarningsTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable" name="DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" xbrli:periodType="duration" />
  <element id="gldd_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems" name="DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <element id="gldd_NetLeverageRatio" name="NetLeverageRatio" nillable="true" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_FixedChargeCoverageRatio" name="FixedChargeCoverageRatio" nillable="true" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_DeferredRevenueReversalOfRevenueRecognized" name="DeferredRevenueReversalOfRevenueRecognized" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="gldd_ProceedsFromVendorPerformanceObligations" name="ProceedsFromVendorPerformanceObligations" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="gldd_PotentiallyDilutiveStockOptionsAndRestrictedStockUnits" name="PotentiallyDilutiveStockOptionsAndRestrictedStockUnits" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_OwnedDomesticSubsidiariesPercent" name="OwnedDomesticSubsidiariesPercent" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <element id="gldd_WarrantyPeriods" name="WarrantyPeriods" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
</schema>
