<?xml version="1.0" encoding="us-ascii"?>
<!-- DFIN ActiveDisclosure(SM) XBRL Schema Document - http://www.dfinsolutions.com/ -->
<!-- Creation Date      : 2022-08-02T18:05:18.5064227+00:00 -->
<!-- Version            : 5.0.1.747 -->
<!-- Package ID         : 5c8123b217174dbba83dd02f0eb74b19 -->
<!-- Copyright (c) 2022 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="gldd_CostsAndEarningsInExcessOfBillingsForCompletedContracts" name="CostsAndEarningsInExcessOfBillingsForCompletedContracts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_AccountsReceivableExcludingContractReceivableCurrent" name="AccountsReceivableExcludingContractReceivableCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_VestingOfRestrictedStockUnitsSharesAndImpactOfSharesWithheldForTaxes" name="VestingOfRestrictedStockUnitsSharesAndImpactOfSharesWithheldForTaxes" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_VestingOfRestrictedStockUnitsValueAndImpactOfSharesWithheldForTaxes" name="VestingOfRestrictedStockUnitsValueAndImpactOfSharesWithheldForTaxes" 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_InterestPaidNetOfCashReceived" name="InterestPaidNetOfCashReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_ScheduleOfFairValuesOfFinancialInstrumentsAndNonfinancialAssetsAndLiabilitiesMeasuredTableTextBlock" name="ScheduleOfFairValuesOfFinancialInstrumentsAndNonfinancialAssetsAndLiabilitiesMeasuredTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <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_GreenLoanOptionMember" name="GreenLoanOptionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_DomesticRateMember" name="DomesticRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_GreenLoanAdvanceRatesMember" name="GreenLoanAdvanceRatesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_TwoThousandTwentyNineNotesMember" name="TwoThousandTwentyNineNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_EightPercentSeniorNotesDueInTwoThousandTwentyTwoMember" name="EightPercentSeniorNotesDueInTwoThousandTwentyTwoMember" type="dtr-types: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_FixedChargeCoverageRatio" name="FixedChargeCoverageRatio" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_LineOfCreditFacilityExpirationDescription" name="LineOfCreditFacilityExpirationDescription" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_OwnedDomesticSubsidiariesPercent" name="OwnedDomesticSubsidiariesPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_FuelHedgeContractsMember" name="FuelHedgeContractsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_ForeignCurrencyExchangeHedgeContractsMember" name="ForeignCurrencyExchangeHedgeContractsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_DerivativeUnderlyingHedgePercent" name="DerivativeUnderlyingHedgePercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_EmployeesAndDirectorsMember" name="EmployeesAndDirectorsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_TwoThousandSeventeenLongTermIncentivePlanMember" name="TwoThousandSeventeenLongTermIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_TwoThousandSevenLongTermIncentivePlanMember" name="TwoThousandSevenLongTermIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_PerformanceObligationExpectedToBeRecognizedAsRevenueYear" name="PerformanceObligationExpectedToBeRecognizedAsRevenueYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_PercentageOfPerformanceObligationToBeRecognizedAsRevenue" name="PercentageOfPerformanceObligationToBeRecognizedAsRevenue" type="dtr-types:percentItemType" 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="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_TypeOfWorkMember" name="TypeOfWorkMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_DredgingMember" name="DredgingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_CapitalDredgingUSMember" name="CapitalDredgingUSMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_CapitalDredgingForeignMember" name="CapitalDredgingForeignMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_BeachNourishmentDredgingMember" name="BeachNourishmentDredgingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_MaintenanceDredgingMember" name="MaintenanceDredgingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_RiversLakesMember" name="RiversLakesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_TypeOfCustomerMember" name="TypeOfCustomerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_FederalGovernmentMember" name="FederalGovernmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_StateAndLocalGovernmentMember" name="StateAndLocalGovernmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_PrivateMember" name="PrivateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_ForeignMember" name="ForeignMember" type="dtr-types: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="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_BillingsInExcessOfCostsAndEarningsMember" name="BillingsInExcessOfCostsAndEarningsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="gldd_IncreasedGrossProfit" name="IncreasedGrossProfit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <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_IndemnificationCommitmentMember" name="IndemnificationCommitmentMember" type="dtr-types: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="dtr-types:volumeItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="gldd_FineForViolation" name="FineForViolation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_PotentialLiabilityForCriminalMatters" name="PotentialLiabilityForCriminalMatters" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_RestitutionOweOnLiabilityForCriminalMattersPreviouslyDeposited" name="RestitutionOweOnLiabilityForCriminalMattersPreviouslyDeposited" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_FinePaidForCriminalMatters" name="FinePaidForCriminalMatters" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
</xsd:schema>
