<?xml version="1.0" encoding="us-ascii"?>
<!--XBRL document created with Crossfire by Rivet Software version 5.4.122.0 http://www.rivetsoftware.com-->
<!--Based on XBRL 2.1-->
<!--Created on: 3/29/2013 10:50:39 AM-->
<!--Modified on: 3/29/2013 10:50:39 AM-->
<linkbase xmlns="http://www.xbrl.org/2003/linkbase" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <roleRef xlink:type="simple" xlink:href="gldd-20120930.xsd#StatementConsolidatedBalanceSheets" roleURI="http://www.gldd.com/role/StatementConsolidatedBalanceSheets" />
  <roleRef xlink:type="simple" xlink:href="gldd-20120930.xsd#StatementConsolidatedStatementsOfOperations" roleURI="http://www.gldd.com/role/StatementConsolidatedStatementsOfOperations" />
  <roleRef xlink:type="simple" xlink:href="gldd-20120930.xsd#StatementConsolidatedStatementsOfComprehensiveIncome" roleURI="http://www.gldd.com/role/StatementConsolidatedStatementsOfComprehensiveIncome" />
  <roleRef xlink:type="simple" xlink:href="gldd-20120930.xsd#StatementCondensedConsolidatedStatementsOfCashFlows" roleURI="http://www.gldd.com/role/StatementCondensedConsolidatedStatementsOfCashFlows" />
  <roleRef xlink:type="simple" xlink:href="gldd-20120930.xsd#DisclosureEarningsPerShareDetails" roleURI="http://www.gldd.com/role/DisclosureEarningsPerShareDetails" />
  <roleRef xlink:type="simple" xlink:href="gldd-20120930.xsd#DisclosureAccountsReceivableAndContractsInProgressScheduleOfAccountsReceivableDetails" roleURI="http://www.gldd.com/role/DisclosureAccountsReceivableAndContractsInProgressScheduleOfAccountsReceivableDetails" />
  <roleRef xlink:type="simple" xlink:href="gldd-20120930.xsd#DisclosureAccountsReceivableAndContractsInProgressScheduleOfAccountsReceivableDetailsAlternative" roleURI="http://www.gldd.com/role/DisclosureAccountsReceivableAndContractsInProgressScheduleOfAccountsReceivableDetailsAlternative" />
  <roleRef xlink:type="simple" xlink:href="gldd-20120930.xsd#DisclosureAccountsReceivableAndContractsInProgressComponentsOfContractsInProgressDetails" roleURI="http://www.gldd.com/role/DisclosureAccountsReceivableAndContractsInProgressComponentsOfContractsInProgressDetails" />
  <roleRef xlink:type="simple" xlink:href="gldd-20120930.xsd#DisclosureAccountsReceivableAndContractsInProgressComponentsOfContractsInProgressDetailsAlternative" roleURI="http://www.gldd.com/role/DisclosureAccountsReceivableAndContractsInProgressComponentsOfContractsInProgressDetailsAlternative" />
  <roleRef xlink:type="simple" xlink:href="gldd-20120930.xsd#DisclosureAccruedExpensesDetails" roleURI="http://www.gldd.com/role/DisclosureAccruedExpensesDetails" />
  <calculationLink xlink:role="http://www.gldd.com/role/StatementConsolidatedBalanceSheets" xlink:type="extended" xlink:title="00100 - Statement - Consolidated Balance Sheets">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_Assets" xlink:label="us-gaap_Assets" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="us-gaap_AssetsCurrent_635001510370085779" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_AssetsCurrent_635001510370085779" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_635001510370085779" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_635001510370085779" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_635001510370085779" order="1" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="us-gaap_AccountsReceivableNetCurrent_635001510370085779" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_635001510370085779" xlink:to="us-gaap_AccountsReceivableNetCurrent_635001510370085779" order="2" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear" xlink:label="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear_635001510370095780" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_635001510370085779" xlink:to="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear_635001510370095780" order="3" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_InventoryNet" xlink:label="us-gaap_InventoryNet_635001510370095780" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_635001510370085779" xlink:to="us-gaap_InventoryNet_635001510370095780" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_635001510370095780" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_635001510370085779" xlink:to="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_635001510370095780" order="5" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_DueFromAffiliateCurrent" xlink:label="us-gaap_DueFromAffiliateCurrent_635001510370095780" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_635001510370085779" xlink:to="us-gaap_DueFromAffiliateCurrent_635001510370095780" order="6" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_635001510370095780" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_PropertyPlantAndEquipmentNet_635001510370095780" order="2" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_InventoryNoncurrent" xlink:label="us-gaap_InventoryNoncurrent_635001510370095780" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_InventoryNoncurrent_635001510370095780" order="3" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures" xlink:label="us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_635001510370095780" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_635001510370095780" order="4" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="us-gaap_OtherAssetsNoncurrent_635001510370095780" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_OtherAssetsNoncurrent_635001510370095780" order="5" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_IntangibleAssetsNetIncludingGoodwill" xlink:label="us-gaap_IntangibleAssetsNetIncludingGoodwill_635001510370095780" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_IntangibleAssetsNetIncludingGoodwill_635001510370095780" order="6" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_InvestmentsInSubsidiaries" xlink:label="gldd_InvestmentsInSubsidiaries_635001510370095780" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="gldd_InvestmentsInSubsidiaries_635001510370095780" order="7" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_634190213612153939" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_Liabilities" xlink:label="us-gaap_Liabilities_635001510370095780" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity_634190213612153939" xlink:to="us-gaap_Liabilities_635001510370095780" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="us-gaap_LiabilitiesCurrent_635001510370105781" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Liabilities_635001510370095780" xlink:to="us-gaap_LiabilitiesCurrent_635001510370105781" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:label="us-gaap_AccountsPayableCurrent_635001510370105781" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_635001510370105781" xlink:to="us-gaap_AccountsPayableCurrent_635001510370105781" order="1" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="us-gaap_AccruedLiabilitiesCurrent_635001510370105781" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_635001510370105781" xlink:to="us-gaap_AccruedLiabilitiesCurrent_635001510370105781" order="2" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_BillingsInExcessOfCost" xlink:label="us-gaap_BillingsInExcessOfCost_635001510370105781" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_635001510370105781" xlink:to="us-gaap_BillingsInExcessOfCost_635001510370105781" order="3" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="us-gaap_LongTermDebtCurrent_635001510370105781" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_635001510370105781" xlink:to="us-gaap_LongTermDebtCurrent_635001510370105781" order="4" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_DueToAffiliateCurrent" xlink:label="us-gaap_DueToAffiliateCurrent_635001510370105781" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_635001510370105781" xlink:to="us-gaap_DueToAffiliateCurrent_635001510370105781" order="5" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_SeniorNotes" xlink:label="us-gaap_SeniorNotes_635001510370105781" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Liabilities_635001510370095780" xlink:to="us-gaap_SeniorNotes_635001510370105781" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_DeferredTaxLiabilitiesNoncurrent" xlink:label="us-gaap_DeferredTaxLiabilitiesNoncurrent_635001510370105781" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Liabilities_635001510370095780" xlink:to="us-gaap_DeferredTaxLiabilitiesNoncurrent_635001510370105781" order="3" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_635001510370105781" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Liabilities_635001510370095780" xlink:to="us-gaap_OtherLiabilitiesNoncurrent_635001510370105781" order="4" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_LongTermNotesPayable" xlink:label="us-gaap_LongTermNotesPayable_635001510370115782" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_Liabilities_635001510370095780" xlink:to="us-gaap_LongTermNotesPayable_635001510370115782" order="5" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_635001510370115782" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity_634190213612153939" xlink:to="us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_635001510370115782" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="us-gaap_StockholdersEquity_635001510370115782" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_635001510370115782" xlink:to="us-gaap_StockholdersEquity_635001510370115782" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_CommonStockValue" xlink:label="us-gaap_CommonStockValue_635001510370115782" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_635001510370115782" xlink:to="us-gaap_CommonStockValue_635001510370115782" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="us-gaap_AdditionalPaidInCapital_635001510370115782" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_635001510370115782" xlink:to="us-gaap_AdditionalPaidInCapital_635001510370115782" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_635001510370115782" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_635001510370115782" xlink:to="us-gaap_RetainedEarningsAccumulatedDeficit_635001510370115782" order="3" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_635001510370115782" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_635001510370115782" xlink:to="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_635001510370115782" order="4" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_MinorityInterest" xlink:label="us-gaap_MinorityInterest_635001510370125783" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_635001510370115782" xlink:to="us-gaap_MinorityInterest_635001510370125783" order="2" use="optional" weight="1" priority="2" />
  </calculationLink>
  <calculationLink xlink:role="http://www.gldd.com/role/StatementConsolidatedStatementsOfOperations" xlink:type="extended" xlink:title="00200 - Statement - Consolidated Statements Of Operations">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_NetIncomeLoss" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ProfitLoss" xlink:label="us-gaap_ProfitLoss_635001510370125783" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_NetIncomeLoss" xlink:to="us-gaap_ProfitLoss_635001510370125783" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_635001510370125783" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_ProfitLoss_635001510370125783" xlink:to="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_635001510370125783" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ForeignCurrencyTransactionLossBeforeTax" xlink:label="us-gaap_ForeignCurrencyTransactionLossBeforeTax_635001510370125783" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_635001510370125783" xlink:to="us-gaap_ForeignCurrencyTransactionLossBeforeTax_635001510370125783" order="1" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_635001510370125783" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_635001510370125783" xlink:to="us-gaap_GainsLossesOnExtinguishmentOfDebt_635001510370125783" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_IncomeLossFromEquityMethodInvestments" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments_635001510370125783" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_635001510370125783" xlink:to="us-gaap_IncomeLossFromEquityMethodInvestments_635001510370125783" order="3" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_InterestIncomeExpenseNet" xlink:label="us-gaap_InterestIncomeExpenseNet_635001510370125783" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_635001510370125783" xlink:to="us-gaap_InterestIncomeExpenseNet_635001510370125783" order="4" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="us-gaap_OperatingIncomeLoss_635001510370125783" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_635001510370125783" xlink:to="us-gaap_OperatingIncomeLoss_635001510370125783" order="5" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_GainLossOnSaleOfOtherAssets" xlink:label="us-gaap_GainLossOnSaleOfOtherAssets_635001510370135784" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_635001510370125783" xlink:to="us-gaap_GainLossOnSaleOfOtherAssets_635001510370135784" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="us-gaap_GeneralAndAdministrativeExpense_635001510370135784" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_635001510370125783" xlink:to="us-gaap_GeneralAndAdministrativeExpense_635001510370135784" order="2" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_GrossProfit" xlink:label="us-gaap_GrossProfit_635001510370135784" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_635001510370125783" xlink:to="us-gaap_GrossProfit_635001510370135784" order="3" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_Revenues" xlink:label="us-gaap_Revenues_635001510370135784" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_GrossProfit_635001510370135784" xlink:to="us-gaap_Revenues_635001510370135784" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ContractRevenueCost" xlink:label="us-gaap_ContractRevenueCost_635001510370135784" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_GrossProfit_635001510370135784" xlink:to="us-gaap_ContractRevenueCost_635001510370135784" order="2" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_IncomeLossFromEquityInvestmentsInSubsidiaries" xlink:label="gldd_IncomeLossFromEquityInvestmentsInSubsidiaries_635001510370135784" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_635001510370125783" xlink:to="gldd_IncomeLossFromEquityInvestmentsInSubsidiaries_635001510370135784" order="6" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="us-gaap_IncomeTaxExpenseBenefit_635001510370135784" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_ProfitLoss_635001510370125783" xlink:to="us-gaap_IncomeTaxExpenseBenefit_635001510370135784" order="2" use="optional" weight="-1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest" xlink:label="us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_635001510370135784" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_NetIncomeLoss" xlink:to="us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_635001510370135784" order="2" use="optional" weight="-1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.gldd.com/role/StatementConsolidatedStatementsOfComprehensiveIncome" xlink:type="extended" xlink:title="00300 - Statement - Consolidated Statements Of Comprehensive Income">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_635001510370135784" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_ComprehensiveIncomeNetOfTax" xlink:to="us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_635001510370135784" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ProfitLoss" xlink:label="us-gaap_ProfitLoss_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_635001510370135784" xlink:to="us-gaap_ProfitLoss_635001510370145785" order="1" use="optional" weight="1" priority="6" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTax_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_635001510370135784" xlink:to="us-gaap_OtherComprehensiveIncomeLossNetOfTax_635001510370145785" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentOnDerivativesIncludedInNetIncomeNetOfTax" xlink:label="us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentOnDerivativesIncludedInNetIncomeNetOfTax_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_OtherComprehensiveIncomeLossNetOfTax_635001510370145785" xlink:to="us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentOnDerivativesIncludedInNetIncomeNetOfTax_635001510370145785" order="1" use="optional" weight="1" priority="7" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax" xlink:label="us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_OtherComprehensiveIncomeLossNetOfTax_635001510370145785" xlink:to="us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax_635001510370145785" order="2" use="optional" weight="1" priority="7" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax" xlink:label="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_OtherComprehensiveIncomeLossNetOfTax_635001510370145785" xlink:to="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax_635001510370145785" order="3" use="optional" weight="1" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" xlink:label="us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_ComprehensiveIncomeNetOfTax" xlink:to="us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_635001510370145785" order="2" use="optional" weight="-1" priority="3" />
  </calculationLink>
  <calculationLink xlink:role="http://www.gldd.com/role/StatementCondensedConsolidatedStatementsOfCashFlows" xlink:type="extended" xlink:title="00500 - Statement - Condensed Consolidated Statements Of Cash Flows">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease" xlink:label="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_634190417159135225" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_634190417159135225" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_IncomeLossFromEquityMethodInvestments" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_IncomeLossFromEquityMethodInvestments_635001510370145785" order="1" use="optional" weight="-1" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ProfitLoss" xlink:label="us-gaap_ProfitLoss_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_ProfitLoss_635001510370145785" order="2" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="us-gaap_DepreciationDepletionAndAmortization_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_DepreciationDepletionAndAmortization_635001510370145785" order="3" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_DeferredIncomeTaxExpenseBenefit_635001510370145785" order="4" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_GainLossOnSaleOfPropertyPlantEquipment" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_635001510370145785" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_635001510370145785" order="5" use="optional" weight="-1" priority="3" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_GainLossOnAdjustmentOfContingentEarnout" xlink:label="gldd_GainLossOnAdjustmentOfContingentEarnout_635001510370155786" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="gldd_GainLossOnAdjustmentOfContingentEarnout_635001510370155786" order="6" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="us-gaap_AmortizationOfFinancingCosts_635001510370155786" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_AmortizationOfFinancingCosts_635001510370155786" order="7" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="us-gaap_ShareBasedCompensation_635001510370155786" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_ShareBasedCompensation_635001510370155786" order="8" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_635001510370155786" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_IncreaseDecreaseInAccountsReceivable_635001510370155786" order="9" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:label="us-gaap_IncreaseDecreaseInInventories_635001510370155786" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_IncreaseDecreaseInInventories_635001510370155786" order="10" use="optional" weight="-1" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_635001510370155786" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_635001510370155786" order="11" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_635001510370155786" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_635001510370155786" order="12" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_635001510370155786" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_GainsLossesOnExtinguishmentOfDebt_635001510370155786" order="13" use="optional" weight="-1" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities" xlink:label="us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities_635001510370155786" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_ExcessTaxBenefitFromShareBasedCompensationOperatingActivities_635001510370155786" order="14" use="optional" weight="-1" priority="3" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ForeignCurrencyTransactionGainLossUnrealized" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossUnrealized_635001510370155786" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_ForeignCurrencyTransactionGainLossUnrealized_635001510370155786" order="15" use="optional" weight="-1" priority="3" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_IncreaseDecreaseInBillingsInExcessOfCost" xlink:label="gldd_IncreaseDecreaseInBillingsInExcessOfCost_635001510370165787" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="gldd_IncreaseDecreaseInBillingsInExcessOfCost_635001510370165787" order="16" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_IncreaseDecreaseInCostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear" xlink:label="gldd_IncreaseDecreaseInCostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear_635001510370165787" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="gldd_IncreaseDecreaseInCostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear_635001510370165787" order="17" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentAssetsAndLiabilitiesNet" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssetsAndLiabilitiesNet_635001510370165787" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_635001510370145785" xlink:to="us-gaap_IncreaseDecreaseInOtherNoncurrentAssetsAndLiabilitiesNet_635001510370165787" order="18" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_635001510370165787" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_634190417159135225" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivities_635001510370165787" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_635001510370165787" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_635001510370165787" xlink:to="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_635001510370165787" order="1" use="optional" weight="-1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_635001510370165787" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_635001510370165787" xlink:to="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_635001510370165787" order="2" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_634190417159135225" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ProceedsFromStockOptionsExercised" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_635001510370165787" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="us-gaap_ProceedsFromStockOptionsExercised_635001510370165787" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_RepaymentsOfLongTermCapitalLeaseObligations" xlink:label="us-gaap_RepaymentsOfLongTermCapitalLeaseObligations_635001510370175788" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="us-gaap_RepaymentsOfLongTermCapitalLeaseObligations_635001510370175788" order="2" use="optional" weight="-1" priority="1" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt" xlink:label="us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt_635001510370175788" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt_635001510370175788" order="3" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_RepaymentsOfSubordinatedDebt" xlink:label="us-gaap_RepaymentsOfSubordinatedDebt_635001510370175788" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="us-gaap_RepaymentsOfSubordinatedDebt_635001510370175788" order="4" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_SeniorSubordinatedNotesRedemptionPremium" xlink:label="gldd_SeniorSubordinatedNotesRedemptionPremium_635001510370175788" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="gldd_SeniorSubordinatedNotesRedemptionPremium_635001510370175788" order="5" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_PaymentOfFinancingAndStockIssuanceCosts" xlink:label="us-gaap_PaymentOfFinancingAndStockIssuanceCosts_635001510370175788" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="us-gaap_PaymentOfFinancingAndStockIssuanceCosts_635001510370175788" order="6" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities" xlink:label="us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities_635001510370175788" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities_635001510370175788" order="7" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_PaymentsOfDividendsShareBasedCompensation" xlink:label="gldd_PaymentsOfDividendsShareBasedCompensation_635001510370175788" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="gldd_PaymentsOfDividendsShareBasedCompensation_635001510370175788" order="8" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_PaymentsOfDividendsCommonStock" xlink:label="us-gaap_PaymentsOfDividendsCommonStock_635001510370185789" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="us-gaap_PaymentsOfDividendsCommonStock_635001510370185789" order="9" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation" xlink:label="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_635001510370185789" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_635001510370185789" order="10" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_PaymentsToMinorityShareholders" xlink:label="us-gaap_PaymentsToMinorityShareholders_635001510370185789" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="us-gaap_PaymentsToMinorityShareholders_635001510370185789" order="11" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_PaymentsForProceedsFromAccountsWithAffiliates" xlink:label="gldd_PaymentsForProceedsFromAccountsWithAffiliates_635001510370185789" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_635001510370165787" xlink:to="gldd_PaymentsForProceedsFromAccountsWithAffiliates_635001510370185789" order="12" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents" xlink:label="us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents_635001510370185789" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_634190417159135225" xlink:to="us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents_635001510370185789" order="4" use="optional" weight="1" priority="2" />
  </calculationLink>
  <calculationLink xlink:role="http://www.gldd.com/role/DisclosureEarningsPerShareDetails" xlink:type="extended" xlink:title="40201 - Disclosure - Earnings Per Share (Details)">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_634997440895536423" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_635001510370195790" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_634997440895536423" xlink:to="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_635001510370195790" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_635001510370195790" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_634997440895536423" xlink:to="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_635001510370195790" order="2" use="optional" weight="1" priority="2" />
  </calculationLink>
  <calculationLink xlink:role="http://www.gldd.com/role/DisclosureAccountsReceivableAndContractsInProgressScheduleOfAccountsReceivableDetails" xlink:type="extended" xlink:title="40301 - Disclosure - Accounts Receivable And Contracts In Progress (Schedule Of Accounts Receivable) (Details)">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AccountsReceivableNet" xlink:label="us-gaap_AccountsReceivableNet" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_AccountsReceivableNoncurrentAndContractReceivableRetainage" xlink:label="gldd_AccountsReceivableNoncurrentAndContractReceivableRetainage_635001510370195790" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AccountsReceivableNet" xlink:to="gldd_AccountsReceivableNoncurrentAndContractReceivableRetainage_635001510370195790" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="us-gaap_AccountsReceivableNetCurrent_635001510370195790" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AccountsReceivableNet" xlink:to="us-gaap_AccountsReceivableNetCurrent_635001510370195790" order="2" use="optional" weight="1" priority="2" />
  </calculationLink>
  <calculationLink xlink:role="http://www.gldd.com/role/DisclosureAccountsReceivableAndContractsInProgressScheduleOfAccountsReceivableDetailsAlternative" xlink:type="extended" xlink:title="40301 - Disclosure - Accounts Receivable And Contracts In Progress (Schedule Of Accounts Receivable) (Details) (Alternative)">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AccountsReceivableNet" xlink:label="us-gaap_AccountsReceivableNet" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AccountsReceivableGross" xlink:label="us-gaap_AccountsReceivableGross_635001510370195790" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AccountsReceivableNet" xlink:to="us-gaap_AccountsReceivableGross_635001510370195790" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivable" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable_635001510370195790" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AccountsReceivableNet" xlink:to="us-gaap_AllowanceForDoubtfulAccountsReceivable_635001510370195790" order="2" use="optional" weight="-1" priority="2" />
  </calculationLink>
  <calculationLink xlink:role="http://www.gldd.com/role/DisclosureAccountsReceivableAndContractsInProgressComponentsOfContractsInProgressDetails" xlink:type="extended" xlink:title="40302 - Disclosure - Accounts Receivable And Contracts In Progress (Components Of Contracts In Progress) (Details)">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_BillingsInExcessOfCost" xlink:label="us-gaap_BillingsInExcessOfCost" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_CostsAndEarningsForContractsInProgress" xlink:label="gldd_CostsAndEarningsForContractsInProgress_635001510370195790" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_BillingsInExcessOfCost" xlink:to="gldd_CostsAndEarningsForContractsInProgress_635001510370195790" order="1" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_BillingsForContractsInProgress" xlink:label="gldd_BillingsForContractsInProgress_635001510370205791" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_BillingsInExcessOfCost" xlink:to="gldd_BillingsForContractsInProgress_635001510370205791" order="2" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrPrograms" xlink:label="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrPrograms" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_CostsAndEarningsInExcessOfBillingsForCompletedContracts" xlink:label="gldd_CostsAndEarningsInExcessOfBillingsForCompletedContracts_635001510370205791" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrPrograms" xlink:to="gldd_CostsAndEarningsInExcessOfBillingsForCompletedContracts_635001510370205791" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_CostsAndEarningsInExcessOfBillingsForContractsInProgress" xlink:label="gldd_CostsAndEarningsInExcessOfBillingsForContractsInProgress_635001510370205791" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrPrograms" xlink:to="gldd_CostsAndEarningsInExcessOfBillingsForContractsInProgress_635001510370205791" order="2" use="optional" weight="1" priority="2" />
  </calculationLink>
  <calculationLink xlink:role="http://www.gldd.com/role/DisclosureAccountsReceivableAndContractsInProgressComponentsOfContractsInProgressDetailsAlternative" xlink:type="extended" xlink:title="40302 - Disclosure - Accounts Receivable And Contracts In Progress (Components Of Contracts In Progress) (Details) (Alternative)">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrPrograms" xlink:label="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrPrograms" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedAfterOneYear" xlink:label="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedAfterOneYear_635001510370205791" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrPrograms" xlink:to="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedAfterOneYear_635001510370205791" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear" xlink:label="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear_635001510370205791" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrPrograms" xlink:to="us-gaap_CostsInExcessOfBillingsOnUncompletedContractsOrProgramsExpectedToBeCollectedWithinOneYear_635001510370205791" order="2" use="optional" weight="1" priority="2" />
  </calculationLink>
  <calculationLink xlink:role="http://www.gldd.com/role/DisclosureAccruedExpensesDetails" xlink:type="extended" xlink:title="40501 - Disclosure - Accrued Expenses (Details)">
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="us-gaap_AccruedLiabilitiesCurrent" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_AccruedInsuranceCurrent" xlink:label="us-gaap_AccruedInsuranceCurrent_635001510370205791" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="us-gaap_AccruedInsuranceCurrent_635001510370205791" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_InterestPayableCurrent" xlink:label="us-gaap_InterestPayableCurrent_635001510370205791" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="us-gaap_InterestPayableCurrent_635001510370205791" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_635001510370205791" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="us-gaap_EmployeeRelatedLiabilitiesCurrent_635001510370205791" order="3" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_TaxesPayableCurrent" xlink:label="us-gaap_TaxesPayableCurrent_635001510370205791" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="us-gaap_TaxesPayableCurrent_635001510370205791" order="4" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="gldd-20120930.xsd#gldd_PercentageOfCompletionAdjustment" xlink:label="gldd_PercentageOfCompletionAdjustment_635001510370215792" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="gldd_PercentageOfCompletionAdjustment_635001510370215792" order="5" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_OtherAccruedLiabilitiesCurrent" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_635001510370215792" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="us-gaap_OtherAccruedLiabilitiesCurrent_635001510370215792" order="6" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgesLiabilities" xlink:label="us-gaap_DerivativeInstrumentsAndHedgesLiabilities_635001510370215792" />
    <calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="us-gaap_DerivativeInstrumentsAndHedgesLiabilities_635001510370215792" order="7" use="optional" weight="1" priority="2" />
  </calculationLink>
</linkbase>
