<?xml version="1.0" encoding="us-ascii"?>
<!-- DFIN ActiveDisclosure(SM) XBRL Schema Document - http://www.dfinsolutions.com/ -->
<!-- Creation Date      : 2019-05-03T16:01:11.0056822+00:00 -->
<!-- Version            : 3.4.7044.22220 -->
<!-- Package ID         : 3770f768af294fa8bf40f5aa57f3783c -->
<!-- Copyright (c) 2019 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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  <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_DisposalGroupIncludingDiscontinuedOperationProvisionForLossOnDisposalNoncurrent" name="DisposalGroupIncludingDiscontinuedOperationProvisionForLossOnDisposalNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_DisposalGroupIncludingDiscontinuedOperationContractRevenuesInExcessOfBillingsCurrent" name="DisposalGroupIncludingDiscontinuedOperationContractRevenuesInExcessOfBillingsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseAssets" name="DisposalGroupIncludingDiscontinuedOperationOperatingLeaseAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="gldd_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseLiabilitiesCurrent" name="DisposalGroupIncludingDiscontinuedOperationOperatingLeaseLiabilitiesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="gldd_DisposalGroupIncludingDiscontinuedOperationOperatingLeaseLiabilitiesNoncurrent" name="DisposalGroupIncludingDiscontinuedOperationOperatingLeaseLiabilitiesNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
</xsd:schema>
