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<!-- DFIN ActiveDisclosure(SM) XBRL Schema Document - http://www.dfinsolutions.com/ -->
<!-- Creation Date      : 2021-02-24T21:25:30.9286291+00:00 -->
<!-- Version            : 5.0.1.571 -->
<!-- Package ID         : 3ee9d9978c0b47fc9587ea77971dc1e3 -->
<!-- Copyright (c) 2021 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="gldd_ProceedsFromLossOfUseClaim" name="ProceedsFromLossOfUseClaim" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_VestingOfRestrictedStockUnitsSharesIncludingImpactOfSharesWithheldForTaxes" name="VestingOfRestrictedStockUnitsSharesIncludingImpactOfSharesWithheldForTaxes" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_VestingOfRestrictedStockUnitsValueIncludingImpactOfSharesWithheldForTaxes" name="VestingOfRestrictedStockUnitsValueIncludingImpactOfSharesWithheldForTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_OtherNonCashRestructuringItems" name="OtherNonCashRestructuringItems" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_AmortizationOfDeferredFinancingCostAndOtherNonCashInterestExpense" name="AmortizationOfDeferredFinancingCostAndOtherNonCashInterestExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_IncreaseDecreaseInCostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear" name="IncreaseDecreaseInCostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_NonCashRepaymentsOfDebtWithProceedsFromSaleLeasebackTransactions" name="NonCashRepaymentsOfDebtWithProceedsFromSaleLeasebackTransactions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_ConsolidationAndBasisOfAccountingPolicyTextBlock" name="ConsolidationAndBasisOfAccountingPolicyTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_RevenueAndCostRecognitionOnContractsPoliciesTextBlock" name="RevenueAndCostRecognitionOnContractsPoliciesTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_ClassificationOfCurrentAssetsAndLiabilitiesPoliciesTextBlock" name="ClassificationOfCurrentAssetsAndLiabilitiesPoliciesTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_EstimatedUsefulLivesByClassOfAssetsTableTextBlock" name="EstimatedUsefulLivesByClassOfAssetsTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_ScheduleOfAdditionalInformationRelatedToLeasesTableTextBlock" name="ScheduleOfAdditionalInformationRelatedToLeasesTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_SupplementalInformationRelatedToLeasesTableTextBlock" name="SupplementalInformationRelatedToLeasesTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_ScheduleOfFairValuesOfFinancialInstrumentsAndNonfinancialAssetsAndLiabilitiesMeasuredTableTextBlock" name="ScheduleOfFairValuesOfFinancialInstrumentsAndNonfinancialAssetsAndLiabilitiesMeasuredTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_ScheduleOfComponentsOfIncomeTaxExpenseBenefitFromContinuingAndDiscontinuedOperationsTableTextBlock" name="ScheduleOfComponentsOfIncomeTaxExpenseBenefitFromContinuingAndDiscontinuedOperationsTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_VehiclesDozersAndOtherLightOperatingEquipmentAndSystemsMember" name="VehiclesDozersAndOtherLightOperatingEquipmentAndSystemsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_HeavyOperatingEquipmentDredgesAndBargesMember" name="HeavyOperatingEquipmentDredgesAndBargesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_NumberOfReportableSegmentsWithGoodwill" name="NumberOfReportableSegmentsWithGoodwill" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_AccruedContractReservesLiabilitiesCurrent" name="AccruedContractReservesLiabilitiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_EightPercentSeniorNotesDueInTwoThousandTwentyTwoMember" name="EightPercentSeniorNotesDueInTwoThousandTwentyTwoMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_LineOfCreditFacilityOptionalIncreaseCapacity" name="LineOfCreditFacilityOptionalIncreaseCapacity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_DomesticRateMember" name="DomesticRateMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_DailyLIBORRateMember" name="DailyLIBORRateMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_SevenPointThreeSevenFiveSeniorNotesDueInTwoThousandNineteenMember" name="SevenPointThreeSevenFiveSeniorNotesDueInTwoThousandNineteenMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_VesselsAndAncillaryEquipmentMember" name="VesselsAndAncillaryEquipmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_NumberOfDaysPriorToScheduledMaturityDate" name="NumberOfDaysPriorToScheduledMaturityDate" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_FixedChargeCoverageRatio" name="FixedChargeCoverageRatio" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_InterestMarginApplicableRate" name="InterestMarginApplicableRate" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_FaceValueOfSeniorNotesIssuedPercentage" name="FaceValueOfSeniorNotesIssuedPercentage" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="gldd_RedemptionOfNotes" name="RedemptionOfNotes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_OwnedDomesticSubsidiariesPercent" name="OwnedDomesticSubsidiariesPercent" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_LongTermDebtCurrentAndNonCurrentExcludingEquipmentNotes" name="LongTermDebtCurrentAndNonCurrentExcludingEquipmentNotes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_FuelHedgeContractsMember" name="FuelHedgeContractsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_DerivativeUnderlyingHedgePercent" name="DerivativeUnderlyingHedgePercent" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_IncomeTaxExpenseBenefitExcludingDiscontinuedOperations" name="IncomeTaxExpenseBenefitExcludingDiscontinuedOperations" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_OperatingLossCarryforwardsExpirationYear" name="OperatingLossCarryforwardsExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_DeferredTaxAssetsOperatingLeaseAssets" name="DeferredTaxAssetsOperatingLeaseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_DeferredTaxLiabilitiesDepreciationAndAmortization" name="DeferredTaxLiabilitiesDepreciationAndAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_DeferredTaxLiabilitiesOperatingLeaseAssets" name="DeferredTaxLiabilitiesOperatingLeaseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_EmployeesAndDirectorsMember" name="EmployeesAndDirectorsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_TwoThousandSeventeenLongTermIncentivePlanMember" name="TwoThousandSeventeenLongTermIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_TwoThousandSevenLongTermIncentivePlanMember" name="TwoThousandSevenLongTermIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_NonQualifiedStockOptionsMember" name="NonQualifiedStockOptionsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_NonEmployeeDirectorsMember" name="NonEmployeeDirectorsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_ShareBasedCompensationArrangementByShareBasedPaymentAwardExercisePeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardExercisePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedExpectedToVest" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedExpectedToVest" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="gldd_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueExpectedToVest" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueExpectedToVest" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="gldd_AnnualRetainerPerNonEmployeeDirectorPercentagePaidInCash" name="AnnualRetainerPerNonEmployeeDirectorPercentagePaidInCash" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_AnnualRetainerPerNonEmployeeDirectorPercentagePaidInCommonStock" name="AnnualRetainerPerNonEmployeeDirectorPercentagePaidInCommonStock" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_AdditionalAnnualRetainerPaidToNonEmployeeDirector" name="AdditionalAnnualRetainerPaidToNonEmployeeDirector" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_AnnualRetainerPerNonEmployeeDirector" name="AnnualRetainerPerNonEmployeeDirector" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_AdditionalPercentageOfAnnualRetainerPaidToNonEmployeeDirectorInCommonStock" name="AdditionalPercentageOfAnnualRetainerPaidToNonEmployeeDirectorInCommonStock" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_PercentageOfPerformanceObligationToBeRecognizedAsRevenue" name="PercentageOfPerformanceObligationToBeRecognizedAsRevenue" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_PerformanceObligationExpectedToBeRecognizedAsRevenueYear" name="PerformanceObligationExpectedToBeRecognizedAsRevenueYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_RevenueFromContractWithCustomerLineItems" name="RevenueFromContractWithCustomerLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_RevenueFromContractWithCustomerTable" name="RevenueFromContractWithCustomerTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_OtherCurrentAndNoncurrentAssetsMember" name="OtherCurrentAndNoncurrentAssetsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_DredgingMember" name="DredgingMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_FederalGovernmentAgenciesMember" name="FederalGovernmentAgenciesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_UseOfEquipmentMember" name="UseOfEquipmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_FederalGovernmentMember" name="FederalGovernmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_TypeOfWorkMember" name="TypeOfWorkMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_CapitalDredgingUSMember" name="CapitalDredgingUSMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_CapitalDredgingForeignMember" name="CapitalDredgingForeignMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_BeachNourishmentDredgingMember" name="BeachNourishmentDredgingMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_MaintenanceDredgingMember" name="MaintenanceDredgingMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_RiversLakesMember" name="RiversLakesMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_TypeOfCustomerMember" name="TypeOfCustomerMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_StateAndLocalGovernmentMember" name="StateAndLocalGovernmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_PrivateMember" name="PrivateMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_ForeignMember" name="ForeignMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_AccountsReceivableBilledForLongTermCompletedContractsOrPrograms" name="AccountsReceivableBilledForLongTermCompletedContractsOrPrograms" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_AccountsReceivableBilledForLongTermContractsOrProgramsInProgress" name="AccountsReceivableBilledForLongTermContractsOrProgramsInProgress" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_CostsAndEarningsForContractsInProgress" name="CostsAndEarningsForContractsInProgress" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_BillingsForContractsInProgress" name="BillingsForContractsInProgress" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_CostsAndEarningsInExcessOfBillingsMember" name="CostsAndEarningsInExcessOfBillingsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_BillingsInExcessOfCostsAndEarningsMember" name="BillingsInExcessOfCostsAndEarningsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_NumberOfSponsored401KPlans" name="NumberOfSponsored401KPlans" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_AssetRetirementsMember" name="AssetRetirementsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_PrecontractCostsMember" name="PrecontractCostsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_CloseoutCostsMember" name="CloseoutCostsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_CostsOfContractRevenuesDepreciationMember" name="CostsOfContractRevenuesDepreciationMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_CostsOfContractRevenuesOtherMember" name="CostsOfContractRevenuesOtherMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_LossOnSaleOfAssetsNetMember" name="LossOnSaleOfAssetsNetMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_BidsBondRange" name="BidsBondRange" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_OutstandingPerformanceBonds" name="OutstandingPerformanceBonds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_RevenueValueRemainingFromOutstandingPerformanceBonds" name="RevenueValueRemainingFromOutstandingPerformanceBonds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_CommitmentsAndContingenciesLineItems" name="CommitmentsAndContingenciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_CommitmentsAndContingenciesTable" name="CommitmentsAndContingenciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_EnvironmentalAndInfrastructureSegmentMember" name="EnvironmentalAndInfrastructureSegmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_WarrantyPeriods" name="WarrantyPeriods" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_QuantityOfOilSpill" name="QuantityOfOilSpill" type="num:volumeItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_PenaltyForViolation" name="PenaltyForViolation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_ValuationAllowancesAndReservesAdditions" name="ValuationAllowancesAndReservesAdditions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
</xsd:schema>
