NORTHWEST PIPE CO
EXHIBIT 10.23
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<TYPE>EX-10.23
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<DESCRIPTION>EXHIBIT 10.23
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<P ALIGN="RIGHT"><FONT SIZE=2><B>EXHIBIT 10.23  </B></FONT></P>

<BR>
<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ka1158_sixth_amendment_to_loan_agreement"> </A></FONT> <FONT SIZE=2><B>SIXTH AMENDMENT TO LOAN AGREEMENT         </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;This amendment to Loan Agreement ("Amendment") is made as of August&nbsp;31, 2000 by and among the following parties: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Bank
of America, N.A., formerly known as Bank of America National Trust and Savings Association ("Bank of America" and a "Lender") </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;U.S.
Bank National Association ("U.S. Bank" and a "Lender") </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Bank
of America, N.A., formerly known as Bank of America National Trust and Savings Association, in its capacity as Agent ("Agent") </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Each
of the several financial institutions which subsequently becomes party to the Loan Agreement pursuant to Section&nbsp;11.7 (each individually a "Lender") </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Northwest
Pipe Company, an Oregon corporation ("Borrower") </FONT></P>

<BR>
<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ka1158_r_e_c_i_t_a_l_s"> </A></FONT> <FONT SIZE=2><B>R E C I T A L S         </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;A.&nbsp;&nbsp;The
Borrower, the Lenders and the Agent are parties to that certain Amended and Restated Loan Agreement dated as of June&nbsp;30, 1998, as amended as of
December&nbsp;23, 1998, June&nbsp;16, 1999, November&nbsp;30, 1999, December&nbsp;30, 1999 and May&nbsp;11, 2000, and as the same may be further amended, modified or extended from time to
time (the "Loan Agreement") and the related Loan Documents described therein. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;B.&nbsp;&nbsp;The
parties desire to amend the Loan Agreement as set forth below: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;NOW,
THEREFORE, the parties agree as follows: </FONT></P>

<BR>
<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ka1158_a_g_r_e_e_m_e_n_t"> </A></FONT> <FONT SIZE=2><B>A G R E E M E N T         </B></FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;1.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;Definitions.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;Capitalized terms used herein and not otherwise defined shall have the meaning given in
the Loan Agreement. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;2.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;Amendment to Section&nbsp;1.1.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;Section&nbsp;1.1 of the Loan Agreement is amended by revising the
definition of "Temporary Supplemental Revolving Loan Commitment" as follows: </FONT></P>

<UL>
<UL>

<P><FONT SIZE=2>"Temporary
Supplemental Revolving Loan Commitment" means Ten Million Dollars ($10,000,000.00) until September&nbsp;30, 2000, after which there shall be no Temporary Supplemental Revolving Loan
Commitment. </FONT></P>

</UL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Amendment
to Section&nbsp;1.1. Section&nbsp;1.1 of the Loan Agreement is amended by revising the following definition of "Temporary Supplemental Revolving Loan Maturity Date" as
follows: </FONT></P>

<UL>
<UL>

<P><FONT SIZE=2>"Temporary
Supplemental Revolving Loan Maturity Date" means September&nbsp;30, 2000. </FONT></P>

</UL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;3.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;Amendment to Section&nbsp;12.1.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;Section&nbsp;12.1 of the Loan Agreement is amended by changing
the ending date of the period during which each lender agrees to make Temporary Supplemental Revolving Loans to September&nbsp;30, 2000. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;4.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;No Further Amendment.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;Except as expressly modified by this Amendment, the Loan Agreement and the
other Loan Documents shall remain unmodified and in full force and effect and the parties hereby ratify their respective obligations thereunder. Without limiting the foregoing, the Borrower expressly
reaffirms and ratifies its obligation to pay or reimburse the Agent and the Lender on request for all reasonable expenses, including legal fees, actually incurred by the Agent or such Lender in
connection with the preparation of this Amendment, any other amendment documents, and the closing of the transactions contemplated hereby and thereby. </FONT></P>

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<P><FONT SIZE=2>
&nbsp;&nbsp;&nbsp;&nbsp;5.</FONT><FONT SIZE=2><I>&nbsp;&nbsp;Miscellaneous.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;Entire
Agreement.&nbsp;&nbsp;This Amendment comprises the entire agreement of the parties with respect to the subject matter hereof and supersedes all prior
oral or written agreements, representations or commitments. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;Counterparts.&nbsp;&nbsp;This
Amendment may be executed in any number of counterparts and by different parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original, and all of which taken together shall constitute one and the same Amendment. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;Governing
Law.&nbsp;&nbsp;This Amendment and the other agreements provided for herein and the rights and obligations of the parties hereto and thereto shall be
construed and interpreted in accordance with the laws of the State of Oregon. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;Certain
Agreements Not Enforceable.&nbsp;&nbsp;UNDER OREGON LAW, MOST AGREEMENTS, PROMISES AND COMMITMENTS MADE BY THE LENDERS AFTER OCTOBER 3, 1989,
CONCERNING LOANS AND OTHER CREDIT EXTENSIONS WHICH ARE NOT FOR PERSONAL, FAMILY OR HOUSEHOLD PURPOSES OR SECURED SOLELY BY THE BORROWER'S RESIDENCE MUST BE IN WRITING, EXPRESS CONSIDERATION, AND BE
SIGNED BY THE LENDERS TO BE ENFORCEABLE. </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>2</FONT></P>

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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;EXECUTED
AND DELIVERED by the duly authorized officers of the parties as of the date first above written. </FONT></P>

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<TD WIDTH="27%"><FONT SIZE=2>BORROWER:</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="71%" COLSPAN=3><FONT SIZE=2>NORTHWEST PIPE COMPANY</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="27%"><FONT SIZE=2>&nbsp;<BR>
&nbsp;</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;<BR>&nbsp;</FONT></TD>
<TD WIDTH="71%" COLSPAN=3><FONT SIZE=2>&nbsp;<BR>
By: BRIAN DUNHAM<BR>
Its: PRESIDENT AND CHIEF OPERATING OFFICER</FONT></TD>
</TR>
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<TD WIDTH="27%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="34%" ALIGN="CENTER"><FONT SIZE=2>Address:</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="34%"><FONT SIZE=2>200 S.W. Market Street, Suite 1800<BR>
Portland OR 97201<BR>
Fax No. (503)&nbsp;240-6615</FONT></TD>
</TR>
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<TD WIDTH="27%"><FONT SIZE=2>&nbsp;<BR>
LENDER:</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;<BR>&nbsp;</FONT></TD>
<TD WIDTH="71%" COLSPAN=3><FONT SIZE=2>&nbsp;<BR>
BANK OF AMERICA, N.A.</FONT></TD>
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<TD WIDTH="27%"><FONT SIZE=2>&nbsp;<BR>
&nbsp;</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;<BR>&nbsp;</FONT></TD>
<TD WIDTH="71%" COLSPAN=3><FONT SIZE=2>&nbsp;<BR>
By: ED KLUSS<BR>
Its: VICE PRESIDENT</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="27%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="34%" ALIGN="CENTER"><FONT SIZE=2>Address:</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="34%"><FONT SIZE=2>Commercial Banking<BR>
121 SW Morrison Street, Suite&nbsp;1700<BR>
Portland OR 97204<BR>
Fax No. (503)&nbsp;275-1391<BR>
Attn: Larry C. Ellis</FONT></TD>
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<TD WIDTH="27%"><FONT SIZE=2>&nbsp;<BR>
&nbsp;</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;<BR>&nbsp;</FONT></TD>
<TD WIDTH="71%" COLSPAN=3><FONT SIZE=2>&nbsp;<BR>
U.S. BANK NATIONAL ASSOCIATION</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="27%"><FONT SIZE=2>&nbsp;<BR>
&nbsp;</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;<BR>&nbsp;</FONT></TD>
<TD WIDTH="71%" COLSPAN=3><FONT SIZE=2>&nbsp;<BR>
By: TIMOTHY G. STEMPEL<BR>
Its: SENIOR VICE PRESIDENT</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="27%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="34%" ALIGN="CENTER"><FONT SIZE=2>Address:</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="34%"><FONT SIZE=2>Oregon Corporate Banking, T-4<BR>
111 SW Fifth Avenue, Suite 400<BR>
Portland OR 97208<BR>
Fax No. (503)&nbsp;275-7290<BR>
Attn: Stephen Mitchell</FONT></TD>
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<TD WIDTH="27%"><FONT SIZE=2>&nbsp;<BR>
AGENT:</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;<BR>&nbsp;</FONT></TD>
<TD WIDTH="71%" COLSPAN=3><FONT SIZE=2>&nbsp;<BR>
BANK OF AMERICA, N.A.</FONT></TD>
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<TD WIDTH="27%"><FONT SIZE=2>&nbsp;<BR>
&nbsp;</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;<BR>&nbsp;</FONT></TD>
<TD WIDTH="34%"><FONT SIZE=2>&nbsp;<BR>
By: DORA A. BROWN<BR>
Its: VICE PRESIDENT</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;<BR>&nbsp;</FONT></TD>
<TD WIDTH="34%"><FONT SIZE=2>&nbsp;<BR>
&nbsp;</FONT></TD>
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<TD WIDTH="27%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="34%" ALIGN="CENTER"><FONT SIZE=2>Address:</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="34%"><FONT SIZE=2>Agency Services<BR>
701 Fifth Avenue, Floor 16<BR>
Seattle WA 98104<BR>
Fax No. (206)&nbsp;358-0971<BR>
Attn: Dora A. Brown</FONT></TD>
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<FONT SIZE=2><A HREF="#ka1158_sixth_amendment_to_loan_agreement">SIXTH AMENDMENT TO LOAN AGREEMENT</A></FONT><BR>
<FONT SIZE=2><A HREF="#ka1158_r_e_c_i_t_a_l_s">R E C I T A L S</A></FONT><BR>
<FONT SIZE=2><A HREF="#ka1158_a_g_r_e_e_m_e_n_t">A G R E E M E N T</A></FONT><BR>
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