Great Lakes Dredge & Dock : Current Investor Presentation

	GREAT LAKES
MITIGATING THE EFFECT OF	DREDGE & DOCK
CORPORATION
CLIMATE CHANGE
FORGING THE WAY	INVESTOR
PRESENTATION
FOR SUSTAINABLE
ENERGY	February 2024

IT ALL STARTS WITH DREDGING®

GREAT LAKES DREDGE & DOCK CORPORATION

[e-mail] | GLDD.COM

SAFE HARBOR

Forward-Looking Statements

This presentation includes "forward-looking" statements within the meaning of Section 27A of the Securities Act of 1933, Section 21E of the Securities Exchange Act of 1934, the Private Securities Litigation Reform Act of 1995 or in releases made by the SEC, all as may be amended from time to time. Such statements include declarations regarding the intent, belief, or current expectations of the Company and its management. The Company cautions that any such forward-looking statements are not guarantees of future performance, and involve a number of risks, assumptions and uncertainties that could cause actual results of the Company and its subsidiaries, or industry results, to differ materially from those expressed or implied by any forward-looking statements contained herein, including, but not limited to, as a result of the factors, risks and uncertainties described in securities filings of the Company made with the SEC, including the Company's most recent Report on Form 10-K and Form 10-Q. You should not place undue reliance upon these forward-looking statements provided herein are made only as of the date

hereof or as a specified date herein and the Company does not have or undertake any obligation to update or revise them, unless required by law.

Non-GAAP Measures

This presentation includes certain non-GAAP measures, including Adjusted EBITDA from continuing operations, Pro Forma Adjusted EBITDA from continuing operations and operational results excluding restructuring. In addition to providing key metrics for management to evaluate the Company's performance, we believe these measurements assist investors in their understanding of period-to-period operating performance and in identifying historical and prospective trends. Reconciliations of these non-GAAP financial measures to the most comparable GAAP measure are available in the Appendix. Investors are urged to consider these non-GAAP measures in addition to, and not in substitution for, measures prepared in accordance with GAAP.

GREAT LAKES DREDGE & DOCK CORPORATION

[e-mail] | GLDD.COM

2

TABLE OF CONTENTS

COMPANY OVERVIEW

FINANCIAL OVERVIEW

APPENDIX

GREAT LAKES DREDGE & DOCK CORPORATION

[e-mail] | GLDD.COM

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GLDD's 2023 HIGHLIGHTS

December 31, 2023,
record backlog of	Q4-23 EBITDA of $41
$1.04 billion
million, highest since
	Q4-21

Full-year 2023 greater than

$100 million in cost

reductions from 2022 levels,

Great Lakes awarded the

Brownsville Rio Grande LNG project, the largest project undertaken in Great Lakes' history, valued at over $300 million

Great Lakes awarded

Port Arthur LNG

project valued at over

$100 million

GLDD market share including LNG as of December 31, 2023, at approximately 50%

71% of backlog

consists of capital

projects, which

includes two LNG

projects

driving improvement in

EBITDA margins and cash

flow

President Biden attends Great Lakes' steel cutting for the Acadia, the first and only Jones Act compliant rock installation vessel

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COMPANY OVERVIEW

GREAT LAKES DREDGE & DOCK CORPORATION

[e-mail] | GLDD.COM

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ABOUT US SNAPSHOT

Great Lakes Dredge & Dock Corporation (GLDD) is the leading provider of dredging services in the United States. With a strong portfolio of major dredging projects, a strong safety record and our extensive experience, we specialize in projects that help improve and protect our nation's infrastructure and coastlines. GLDD is the only U.S. dredging service provider with a long history of performing significant international projects. In addition, we are the only dredging contractor entering into the emerging U.S. offshore wind market. Our diverse fleet of equipment includes hopper, mechanical and hydraulic dredges, and approximately 200 support vessels. GLDD is a publicly-traded company with corporate headquarters in Houston, Texas, regional business offices in Jacksonville and Staten Island, and marine yards in five U.S. locations.

• LEADING DREDGER IN THE UNITED STATES
• PORT DEEPENING, COASTAL PROTECTION & BARRIER ISLANDS & LAND RECLAMATION
• EXPANDING CORE BUSINESS INTO THE RAPIDLY DEVELOPING OFFSHORE WIND ENERGY INDUSTRY
• AN INCIDENT & INJURY-FREE® (IIF®) COMPANY
• MARKET LEADER WITH 133-YEAR HISTORY
• CLIENTS INCLUDE FEDERAL, STATE, LOCAL, AND FOREIGN GOVERNMENTS, DOMESTIC AND FOREIGN PRIVATE COMPANIES, SUCH AS UTILITIES AND ENERGY COMPANIES, LNG PRODUCERS, AND OFFSHORE WIND DEVELOPERS

RECORD BACKLOGa $1.04 BILLION LOW BIDS AND OPTIONS PENDING $179 MILLION Q4 2023 AWARDS $163 MILLION Q4 2023 ADJUSTED EBITDA $41 MILLION

$ as of December 31, 2023

GREAT LAKES DREDGE & DOCK CORPORATION

(a) Backlog amount does not include approximately $45 million related to offshore wind contracts.

[e-mail] | GLDD.COM

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ABOUT US WORK WE DO

SPECIALIZING IN PROJECTS THAT HELP IMPROVE AND PROTECT OUR NATION'S INFRASTRUCTURE AND COASTLINES

CAPITAL	COASTAL PROTECTION
32% OF REVENUE(A)	33% OF REVENUE(A)

↓	↓
LNG, PORT DEEPENING /	CREATING AND REBUILDING
EXPANSION, COASTAL
BEACHES
RESTORATION, LAND
BID MARKET SHARE(B) 18%
RECLAMATION, & EXCAVATION
OF UNDERWATER TRENCHES
BID MARKET SHARE(B) 36%

MAINTENANCE		FOREIGN
32% OF REVENUE(A)		0% OF REVENUE(A)
↓		↓

Maintenance	Capital,
+ R&L, 35%	32%

BALANCED MIX OF REVENUE

Coastal

Protection,

33%

RIVERS & LAKES

3% OF REVENUE(A)

↓

MAINTAINING DEPTH OF	INTERNATIONAL LAND	INLAND MAINTENANCE AND LAKE
RECLAMATIONS, CHANNEL	DREDGING, ENVIRONMENTAL &
WATERWAYS AND HARBORS
DEEPENING & PORT	HABITAT RESTORATION
BID MARKET SHARE(B) 40%
	INFRASTRUCTURE DEVELOPMENT	BID MARKET SHARE(B) 6%
	3-YEAR AVERAGE REVENUE:
	$7MM	GREAT LAKES DREDGE & DOCK CORPORATION
(A) Revenue of FY 2023			[e-mail] | GLDD.COM
(B) The Company's dredging bid market is defined as the aggregate dollar value of domestic projects on which the Company bid or could have bid if not for capacity

constraints. Bid market share represents bid market average over the prior three years (2021-2023)	7

ABOUT US DREDGING FLEET

LARGE & DIVERSE FLEET WITH THREE MAJOR VESSELS ADDED TO FLEET SINCE 2018

HOPPER

• 5 U.S. VESSELS (1 ADDITIONAL VESSEL UNDER CONSTRUCTION)
• THE ELLIS ISLAND IS THE LARGEST HOPPER IN THE U.S. FLEET
• HIGHLY MOBILE, ABLE TO OPERATE IN ROUGH WATERS
• LITTLE INTERFERENCE WITH OTHER SHIP TRAFFIC

MECHANICAL

• 4 U.S.VESSELS
• OPERATES ONE ENVIRONMENTALLY FRIENDLY ELECTRIC CLAMSHELL DREDGE
• THE DREDGE 58 IS ONE OF THE LARGEST CLAMSHELLS IN THE U.S. FLEET
• MANEUVERABILITY IN TIGHT AREAS SUCH AS DOCKS AND TERMINALS

HYDRAULIC

• 5 OCEAN CLASS U.S.VESSELS
• 3 INLAND CLASS U.S. VESSELS
• MOST POWERFUL ROCK CUTTER DREDGES IN U.S. MARKET
• SUPPORTED BY 8 BOOSTER PUMPING STATIONS
• CAPABLE OF EXCAVATING CHALLENGING SOILS, INCLUDING ROCK

GREAT LAKES DREDGE & DOCK CORPORATION

[e-mail] | GLDD.COM

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ABOUT US DOMESTIC COMPETITION

3-YEAR AVERAGE

DOMESTIC BID MARKET SHARE ($2,004 MILLION)(a)

NUMBER OF

DREDGES

					OTHERS
	33%	20%			26%
		7%	6%	5%	2%
	17(b) 11 9	4	4	4 N/A

	GREAT LAKES DREDGE & DOCK CORPORATION
(a) 2021 - 2023 including Rivers & Lakes, excludes LNG	[e-mail] | GLDD.COM
(b) Excluding G.L. 53 (retired in 2023) and one hopper under construction
.	9

2023 BIDDING RESULTS

MAJOR PROJECTS IN 2023 BID MARKET

$ millions

	GREAT LAKES DREDGE & DOCK CORPORATION
a) Total Market without LNG $2.2B	[e-mail] | GLDD.COM
b) Total Market with LNG $2.7B	10