Mail Stop 7010

      December 14, 2005

Mr. Douglas B. Mackie
Great Lakes Dredge & Dock Corporation
2122 York Road
Oak Brook, IL 60523

      Re:	Great Lakes Dredge & Dock Corporation
		Form 10-K for the year ended December 31, 2004
      Filed March 30, 2005
      Forms 8-K filed February 1, 2005 and April 26, 2005
      File No. 333-64687

Dear Mr. Mackie:

      We have reviewed your response letter dated December 2, 2005
and have the following additional comment.  Where indicated, we
think
you should revise your document in response to these comments.  If
you disagree, we will consider your explanation as to why our
comment
is inapplicable or a revision is unnecessary.  Please be as
detailed
as necessary in your explanation.  In some of our comments, we may
ask you to provide us with information so we may better understand
your disclosure.  After reviewing this information, we may raise
additional comments.

FORM 10-K FOR THE YEAR ENDED DECEMBER 31, 2004

Item 7 - Management`s Discussion and Analysis, page 21

Costs and Expenses, page 22

1. We note your response to comment 1 from our letter dated
September
29, 2005.  Please revise your footnotes in future annual and
interim
filings to expand your discussion of your method for allocating
fixed
equipment costs to interim periods.  Given that your business is
very
capital intensive, and because you use percentage of completion
accounting, we believe that this information is an important part
of
understanding your accounting policies.  In this regard, please
disclose the following:

* In interim reporting periods, you record certain fixed equipment
expenses based on an estimate of total annual costs on a contract.
The amount of the fixed equipment costs recorded is based on the
proportion of actual revenue earned in the interim period relative
to
the estimated total revenue to be earned for the year on each
contract.

* In the fourth quarter, the fixed equipment expense recorded for
all
contracts is the remaining amount necessary such that your fixed
equipment expense for the year equals your actual fixed equipment
costs for the year.

* As a result of this methodology, the actual fixed equipment
costs
incurred in any interim period may be higher or lower than the
recorded expense.

* Any other information that you believe is important to assist
your
investors in understanding your accounting policy.

You response should show us what this expanded disclosure will
look
like.


*	*	*


		Please respond to these comments within 10 business
days,
or tell us when you will provide us with a response.  Please
provide
us with a response letter that keys your responses to our comments
and provides any requested information.  Detailed letters greatly
facilitate our review.  Please understand that we may have
additional
comments after reviewing your responses to our comments.


      If you have any questions regarding these comments, please
direct them to Jennifer Thompson, Staff Accountant, at (202) 551-
3737
or, in her absence, to John Hartz, Senior Assistant Chief
Accountant,
at (202) 551-3689 or the undersigned at (202) 551-3768.

      Sincerely,



      John Cash
      Accounting Branch Chief

Mr. Douglas B. Mackie
Great Lakes Dredge & Dock Corporation
December 14, 2005
Page 1


UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549-7010

         DIVISION OF
CORPORATION FINANCE