EXHIBIT 5
                      [DECHERT PRICE & RHOADS LETTERHEAD]



 


                                 December 11, 1998


Great Lakes Dredge & Dock Corporation
2122 York Road
Oak Brook, Illinois 60521


                     Re:  Registration Statement on Form S-4
                          SEC File No. 333-64687
                          ----------------------


Gentlemen and Ladies:

          We have acted as special counsel to Great Lakes Dredge & Dock
Corporation, a Delaware corporation (the "Company") and Great Lakes Dredge &
Dock Company, a New Jersey corporation; Great Lakes International, Inc., a
Delaware corporation; Dawson Dredging Company, a Delaware corporation; Gates
Construction Corp., a New Jersey corporation; and Fifty-Three Dredging
Corporation, a New Jersey corporation (collectively, the "Guarantors") in
connection with the preparation and filing of the Registration Statement on Form
S-4 (Registration No. 333-64687), originally filed on September 29, 1998 with
the Securities and Exchange Commission under the Securities Act of 1933, as
amended (the "Securities Act"), and the Trust Indenture Act of 1939, as amended,
as subsequently amended by an amendment to be filed today (the "Registration
Statement"). The Registration Statement relates to the proposed issuance of up
to $115 million aggregate principal amount of Series B 11 1/4% Senior
Subordinated Notes due 2008 (the "Exchange Notes") of the Company and the
guarantee thereof (the "Exchange Guaranties") by each of the Guarantors. The
Exchange Notes are to be issued in exchange for an equal aggregate principal
amount of the Company's outstanding Series A 11 1/4% Senior Subordinated Notes
due 2008 (the "Existing Notes") and the Guarantors' guaranties

 
Great Lakes Dredge & Dock Corporation
December 11, 1998
Page 2



thereof pursuant to the Registration Rights Agreement dated August 19, 1998
among the Company, the Guarantors and Donaldson, Lufkin & Jenrette Securities
Corporation. The Exchange Notes are to be issued pursuant to the terms of an
Indenture, filed as Exhibit 4.01 to the Registration Statement (the
"Indenture"), among the Company, the Guarantors and The Bank of New York, as
trustee.

          We have participated in the preparation of the Registration Statement
and have made such legal and factual examination and inquiry which we have
deemed advisable for the rendering of the opinions set forth below.  In making
our examination, we have assumed the genuineness of all signatures, the
authenticity of all documents submitted to us as originals and the conformity to
all authentic original documents of all documents submitted to us as copies.
Based on the foregoing, it is our opinion that:

          1.  The Exchange Notes have been duly authorized by the Company, and
when the Registration Statement has been declared effective, when the Exchange
Notes have been duly executed, authenticated and delivered in accordance with
the terms of the Indenture, and when the Exchange Notes have been issued and
delivered against the exchange of the Existing Notes in accordance with the
terms set forth in the Prospectus included in the Registration Statement, the
Exchange Notes will constitute legal, valid and binding obligations of the
Company, enforceable against the Company in accordance with their terms, subject
to applicable bankruptcy, insolvency, fraudulent conveyance, moratorium,
reorganization or other similar laws affecting creditors' rights or debtors'
obligations and to general principles of equity.

          2.  The Exchange Guaranties have been duly authorized by the
respective Guarantors, and when the Registration Statement has been declared
effective, when the Exchange Notes have been duly executed, authenticated and
delivered in accordance with the terms of the Indenture, and when the Exchange
Notes have been issued and delivered against the exchange of the Existing Notes
in accordance with the terms set forth in the Prospectus included in the
Registration Statement, the Exchange Guaranties will constitute the legal, valid
and binding obligations of the respective Guarantors, enforceable against the
respective Guarantors in accordance with their terms, subject to applicable
bankruptcy, insolvency, fraudulent conveyance, moratorium, reorganization or
other similar laws affecting creditors' rights or debtors' obligations and to
general principles of equity.

 
Great Lakes Dredge & Dock Corporation
December 11, 1998
Page 3



          The opinions expressed herein are limited to the laws of the United
States of America, the State of New York, the Delaware General Corporation Law
and the New Jersey Business Corporation Act, and we express no opinion
concerning any other laws.

          The opinions expressed herein are rendered for your benefit in
connection with the transaction contemplated herein. The opinions expressed
herein may not be used or relied upon by any other person, nor may this letter
or any copies hereof be furnished to a third party, filed with a governmental
agency, quoted, cited or otherwise referred to without our prior written
consent, except as noted below.

          We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement, and to the use of our name in the Prospectus contained
therein under the caption "Legal Matters." In giving such consent we do not
thereby admit that we are in the category of persons whose consent is required
under Section 7 of the Securities Act.


                                 Very truly yours,

                                 /s/ Dechert Price & Rhoads