Exhibit 10.1

EIGHTH AMENDMENT TO

AMENDED AND RESTATED CREDIT AGREEMENT

This EIGHTH AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT (“Amendment”) is
entered into effective as of October 15, 2010 (the “Effective Date”), among
NORTHWEST PIPE COMPANY, an Oregon corporation (the “Borrower”), and BANK OF
AMERICA, N.A., as Administrative Agent (the “Administrative Agent”).

RECITALS

Borrower, Administrative Agent and certain lenders party thereto from time to
time are parties to that certain Amended and Restated Credit Agreement entered
into as of May 31, 2007 (as amended, modified or supplemented from time to time,
the “Credit Agreement”). Borrower and Administrative Agent desire to amend the
Credit Agreement as set forth herein. The Required Lenders (as that term is
defined in the Credit Agreement), and Bank of America, N.A., as Swing Line
Lender and L/C Issuer, have consented to the amendments to the Credit Agreement
set forth herein as indicated by their signatures below.

NOW THEREFORE, the parties agree as follows:

AGREEMENT

1. Recitals. The Recitals are true.

2. Definitions. Capitalized terms used herein and not otherwise defined shall
have the meanings given in the Credit Agreement.

3. Amendments to Definitions.

(a) The definition of “Consolidated EBITDA” set forth in Section 1.01 of the
Credit Agreement is amended in its entirety to read as follows:

“‘Consolidated EBITDA’ means for any period, for the Borrower and its
Subsidiaries on a consolidated basis, an amount equal to Consolidated Net Income
for such period plus (a) the following to the extent deducted in calculating
such Consolidated Net Income: (i) Consolidated Interest Charges for such period,
(ii) the provision for federal, state, local and foreign income taxes payable by
the Borrower and its Subsidiaries for such period, (iii) depreciation and
amortization expense, (iv) non-recurring expenses constituting severance
payments to Brian Dunham in connection with the termination of his employment
with Borrower, not to exceed $570,000 in the aggregate, to the extent such
expenses are not repaid to Borrower pursuant to the terms of Brian Dunham’s
separation agreement with Borrower, and (v) other expenses in such period
reducing Consolidated Net Income for such period

 

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which did not or will not require a cash settlement in such period or any future
period (including but not limited to impairment charges, costs associated with
exit or disposal activities and stock based compensation), minus (b) all items
increasing Consolidated Net Income for such period which did not or will not
result in a cash settlement in such period or any future period, including any
gain from the sale of assets. For purposes of calculating Consolidated EBITDA,
EBITDA for permitted acquisitions made by the Borrower, based on financial
statements and information reported to the SEC shall be included in the
calculation of Consolidated EBITDA. The permitted acquisitions’ EBITDA shall be
incorporated on a decreasing pro-rata basis, with 100% of the permitted
acquisitions’ EBITDA included in the calculation for the first calendar quarter
end following the close of the acquisition, 75% included in the second quarter
end, 50% included in the third quarter end and 25% included in the fourth
quarter end. Beginning with the fifth quarter following the closing of the
acquisition, the EBITDA for the acquisitions’ prior fiscal year shall no longer
be incorporated in the calculation of Consolidated EBITDA.”

(b) The definition of “Consolidated Net Income” set forth in Section 1.01 of the
Credit Agreement is amended in its entirety to read as follows:

“‘Consolidated Net Income’ means, for any period, for Borrower and its
Subsidiaries on a consolidated basis, the net income of Borrower and its
Subsidiaries for that period, excluding (a) one-time accounting fees, attorneys
fees and similar costs and expenses actually incurred by Borrower during that
period in connection with the internal accounting investigation, and the related
investigation by the SEC, described in Borrower’s Form 8-K filed with the SEC on
March 16, 2010, (i) during its 2010 fiscal year of up to $7,000,000 in the
aggregate, and (ii) during its 2011 fiscal year of up to $3,500,000 in the
aggregate, and (b) without duplication of any losses described in clause
(a) above, extraordinary gains and extraordinary losses for that period. The
terms ‘extraordinary gains and extraordinary losses’ in this definition include
gains and losses from a material event or transaction that is unusual in nature
or occurs infrequently and results in a gain or loss in excess of $2,500,000.”

 

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(c) The definition of “Temporary Availability Block” set forth in Section 1.01
of the Credit Agreement is amended in its entirety to read as follows:

“‘Temporary Availability Block’ means (a) from October 15, 2010, until delivery
by Borrower of (i) the financial statements required to be delivered pursuant to
Section 6.01(a)(i) hereof for Borrower’s fiscal year ending December 31, 2009,
(ii) the financial statements required to be delivered pursuant to
Section 6.01(b)(i) hereof with respect to the fiscal quarters of Borrower and
its Subsidiaries ending March 31, 2010, and June 30, 2010, and (iii) the
financial statements required to be delivered pursuant to Section 6.01(f)
hereof, the amount of $15,000,000, (b) from the date of delivery of the last to
be delivered item described in clause (a) above until delivery by Borrower of
the Compliance Certificate required to be delivered pursuant to Section 6.02(b)
hereof with respect to the fiscal quarter of Borrower and its Subsidiaries
ending March 31, 2011, the amount of $7,500,000, and (c) thereafter, $0.”

4. Amendments to Section 6.01 of the Credit Agreement.

(a) Section 6.01(a)(i) of the Credit Agreement is amended in its entirety to
read as follows:

“(a)(i) as soon as available, but in any event within 308 days after the end of
Borrower’s 2009 fiscal year, and within 105 days after the end of each other
fiscal year of the Borrower, a consolidated balance sheet of the Borrower and
its Subsidiaries as at the end of such fiscal year, and the related consolidated
statements of income or operations, shareholders’ equity and cash flows for such
fiscal year, setting forth in each case in comparative form the figures for the
previous fiscal year, all in reasonable detail and prepared in accordance with
GAAP, such consolidated statements to be audited and accompanied by a report and
opinion of an independent certified public accountant of nationally recognized
standing reasonably acceptable to the Required Lenders, which report and opinion
shall be prepared in accordance with generally accepted auditing standards and
shall not be subject to any “going concern” or like qualification or exception
or any qualification or exception as to the scope of such audit; and”

(b) Section 6.01(b)(i) of the Credit Agreement is amended in its entirety to
read as follows:

“(b)(i) as soon as available, but in any event within (x) 218 days after the end
of the first fiscal quarter of Borrower’s 2010 fiscal year, (y) 127 days after
the end of the second fiscal quarter of Borrower’s 2010 fiscal year, and (z) 60
days after the end of each of the other first three fiscal quarters of each
fiscal year of Borrower, a consolidated balance sheet of the Borrower and its
Subsidiaries as at the end of such fiscal quarter, and the related consolidated
statements of income or operations, shareholders’ equity and cash flows for such
fiscal quarter and for the portion of

 

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the Borrower’s fiscal year then ended, setting forth in each case in comparative
form the figures for the corresponding fiscal quarter of the previous fiscal
year and corresponding portion of the previous fiscal year, all in reasonable
detail and prepared in accordance with GAAP, such consolidated statements to be
certified by the chief executive officer, chief financial officer, treasurer or
controller of the Borrower as fairly presenting the financial condition, results
of operations, shareholders’ equity and cash flows of the Borrower and its
Subsidiaries in accordance with GAAP, subject only to normal year end audit
adjustments and the absence of footnotes; and”

(c) A new Section 6.01(f) is added to the Credit Agreement, to read in its
entirety as follows:

“(f) as soon as available, but in any event not later than November 4, 2010, a
consolidated balance sheet of the Borrower and its Subsidiaries as at the end of
the fiscal quarter of Borrower ending September 30, 2009, and the related
consolidated statements of income or operations, shareholders’ equity and cash
flows for such fiscal quarter and for the portion of the Borrower’s fiscal year
then ended, setting forth in comparative form the figures for the corresponding
fiscal quarter of the previous fiscal year and corresponding portion of the
previous fiscal year, and reflecting Borrower’s restated financial results, all
in reasonable detail and prepared in accordance with GAAP, such consolidated
statements to be certified by the chief executive officer, chief financial
officer, treasurer or controller of the Borrower as fairly presenting the
financial condition, results of operations, shareholders’ equity and cash flows
of the Borrower and its Subsidiaries in accordance with GAAP, subject only to
normal year end audit adjustments and the absence of footnotes.”

5. Release. As a material part of the consideration of Administrative Agent
entering into, and the Required Lenders consenting to, this Amendment, Borrower
hereby releases and forever discharges Administrative Agent, the Lenders and
each of their respective successors, assigns, officers, managers, directors,
shareholders, employees, agents, attorneys, representatives, parent
corporations, subsidiaries, and affiliates (all the foregoing, collectively, the
“Releasees” and individually, a “Releasee”), jointly and severally from any and
all claims, counterclaims, demands, damages, debts, agreements, covenants,
suits, contracts, obligations, liabilities, accounts, offsets, rights, actions
and causes of action of any nature whatsoever, including all claims, demands,
and causes of action for contribution and indemnity, whether arising at law or
in equity, whether presently possessed or possessed in the future, whether known
or unknown, whether liability be direct or indirect, liquidated or unliquidated,
whether presently accrued or to accrue hereafter, whether absolute or
contingent, foreseen or unforeseen, and whether or not heretofore asserted,
which Borrower may have or claim to have against Releasees (or any one or more
of them); provided, however, that neither Administrative Agent

 

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nor any Lender nor any other Releasee shall be released hereby from: (i) any
obligation to pay to Borrower any amounts that Borrower may have on deposit with
Administrative Agent or any Lender, in accordance with applicable laws and the
terms of the documents establishing any such deposit relationship; or (ii) any
claim (including without limitation any claim for breach of the Credit Agreement
or other Loan Document) arising from any action, inaction or conduct of
Administrative Agent or the Lenders or the other Releasees after the effective
date of this Amendment.

6. No Further Amendment, Expenses. Except as expressly modified by this
Amendment, the Credit Agreement and the other Loan Documents shall remain
unmodified in full force and effect and the parties hereby ratify their
respective obligations thereunder. Without limiting the foregoing, Borrower
expressly reaffirms and ratifies its obligation to pay or reimburse
Administrative Agent and Lenders on request for all reasonable expenses,
including legal fees actually incurred by Administrative Agent and Lenders in
connection with the preparation of this Amendment, any other amendment documents
and the closing of the transaction contemplated hereby and thereby.

7. Miscellaneous.

(a) Counterparts. 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, it being understood that the
Administrative Agent may rely on a facsimile counterpart signature page hereof
for purpose of determining whether a party hereto has executed a counterpart
hereof.

(b) Governing Law. 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.

(c) Certain Agreements Not Enforceable. UNDER OREGON LAW, MOST AGREEMENTS,
PROMISES AND COMMITMENTS MADE BY THE LENDERS 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.

[Signatures appear on the following page.]

 

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EXECUTED AND DELIVERED by the duly authorized officers of the parties as of the
date first above written.

 

BORROWER:    NORTHWEST PIPE COMPANY    By:
                                         
                                                            Name:
                                         
                                                       Title:
                                         
                                                       ADMINISTRATIVE AGENT:   

BANK OF AMERICA, N.A., as

Administrative Agent

   By:                                          
                                                            Name:
                                         
                                                       Title:
                                         
                                                      

CONSENTED TO BY THE REQUIRED

LENDERS:

      BANK OF AMERICA, N.A.    By:                                          
                                                            Name:
                                         
                                                       Title:
                                         
                                                      

 

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UNION BANK, N.A., formerly known as

Union Bank of California, N.A.

   By:                                                                      
                                Name:                            
                                                                    
Title:                                                                      
                              HSBC BANK USA, NATIONAL ASSOCIATION   
By:                                                                      
                                Name:                            
                                                                    
Title:                                                                      
                              U.S. BANK NATIONAL ASSOCIATION   
By:                                                                      
                                Name:                            
                                                                    
Title:                                                                      
                          

CONSENTED TO BY SWING LINE

LENDER AND L/C ISSUER

     

BANK OF AMERICA, N.A., as Swing Line

Lender and L/C Issuer

   By:                                                                      
                                Name:                            
                                                                    
Title:                                                                      
                          

 

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