Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
MADISON DEARBORN CAPITAL PARTNERS IV LP
   2. Issuer Name and Ticker or Trading Symbol
Great Lakes Dredge & Dock CORP [GLDD] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
GREAT LAKES DREDGE & DOCK CORPORATION, 2122 YORK ROAD		 3. Date of Earliest Transaction (Month/Day/Year)
08/01/2007
(Street)

OAKBROOK, IL 60523		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 08/01/2007   S   12,459,462 D $ 7.05 14,248,940 I See Footnote (1)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
MADISON DEARBORN CAPITAL PARTNERS IV LP
GREAT LAKES DREDGE & DOCK CORPORATION
2122 YORK ROAD
OAKBROOK, IL 60523		     X    
MADISON DEARBORN PARTNERS IV LP
GREAT LAKES DREDGE & DOCK CORPORATION
2122 YORK ROAD
OAKBROOK, IL 60523		     X    
MADISON DEARBORN PARTNERS LLC
GREAT LAKES DREDGE & DOCK CORPORATION
2122 YORK ROAD
OAKBROOK, IL 60523		     X    

Signatures

 Madison Dearborn Capital Partners IV, L.P. By: Madison Dearborn Partners IV, L.P., its General Partner By: Madison Dearborn Partners, LLC, its General Partner By: /s/ Thomas S. Souleles, Managing Director   08/03/2007
**Signature of Reporting Person Date
 Madison Dearborn Partners IV, L.P. By: Madison Dearborn Partners, LLC, its General Partner By: /s/ Thomas S. Souleles, Managing Director   08/03/2007
**Signature of Reporting Person Date
 Madison Dearborn Partners, LLC By: /s/ Thomas S. Souleles, Managing Director   08/03/2007
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Includes 14,248,940 shares directly owned by Madison Capital Partners IV, L.P. ("MDCP"). Madison Dearborn Partners, IV, L.P. ("MDP IV") is the general partner of MDCP. John A. Canning, Jr., Paul J. Finnegan and Samuel M. Mencoff are the sole members of a limited partner committee of MDP IV that has the power, acting by majority vote, to vote or dispose of the shares held by MDCP. Each of MDP, MDP IV and the members of the limited partner committee of MDP IV disclaims beneficial ownership of the shares held directly by MDCP except to the extent of his or its respective pecuniary interest therein.

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