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                                                                    EXHIBIT 10.4

                            2006 EMPLOYMENT AGREEMENT

                      Columbia River Bank - Britt W. Thomas

      This Employment Agreement (the "Agreement") is made and entered into this
15th day of April, 2006 by and between Columbia River Bank, an Oregon
corporation ("Bank") and Britt W. Thomas ("Employee").

                                    RECITALS

      (1) Bank is a state-chartered Oregon financial institution, and is the
wholly owned subsidiary of Columbia Bancorp ("Bancorp"). Bancorp's principal
office is at 401 East Third Street, Suite 200, The Dalles, Oregon 97058.

      (2) Bank desires to employ Employee as an officer of Bank on the terms and
conditions set forth herein.

      Now, therefore, it is agreed:

      1. RELATIONSHIP AND DUTIES.

      1.1 EMPLOYMENT AND TITLE. Bank shall employ Employee as an officer of Bank
with such title as the President and Chief Executive Officer of the Bank shall
designate. Subject to the terms and conditions hereof, employee shall perform
such duties and exercise such authority as are customarily performed and
exercised by persons holding such office, subject to the general direction of
the President and Chief Executive Officer of the Bank and of the Boards of
Directors of Bancorp and the Bank. Such services and duties shall be exercised
in good faith and in accordance with standards of reasonable business judgment.
As used herein, references to "Bank" shall be deemed to also refer to and
include Bancorp where the context requires.

      1.2 DUTIES; CONFLICTS. Employee shall devote his full time, attention and
efforts to the diligent performance of his duties as an officer of the Bank.
Employee will not accept employment with any other individual, corporation,
partnership, governmental authority or any other entity, or engage in any other
venture for profit which Bancorp, or any subsidiary, parent, sister or
affiliated corporation of Bancorp, considers to be in conflict with their best
interests or to be in competition with their business, or which may interfere in
any way with Employee's performance of his duties hereunder.

      1.3 SERVICE ON OTHER COMPANY BOARDS. Nothing in the Agreement shall
prohibit Employee from serving on the board of directors of any profit or
non-profit corporation not in direct competition with Bancorp or with any
subsidiary, parent, sister or affiliated corporation of Bancorp. In addition,
Employee may own stock in any other corporation whether or not the stock is
publicly traded; provided, that if such corporation

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operates a business in competition with Bancorp Employee may not own more than
five percent (5%) of the outstanding shares of such corporation.

      2. TERM OF EMPLOYMENT.

      2.1 TWO-YEAR TERM. The term of employment under the Agreement shall begin
on April 15, 2006 and end on April 14, 2008.

      3. TERMINATION.

      3.1 DEFINITION. As used in the Agreement, "termination" shall mean the
termination of Employee's employment relation with Bank, whether initiated by
Bank or by Employee, and whether for cause or without cause.

      3.2 TERMINATION EVENTS. Notwithstanding any other provisions of the
Agreement, the employment of Employee shall terminate immediately on the earlier
to occur of any of the following:

            3.2.1 Employee's death;

            3.2.2 Employee's complete disability. "Complete disability" as used
herein shall mean the inability of Employee, due to illness, accident, or other
physical or mental incapacity, to perform the services required under the
Agreement for an aggregate of ninety (90) days within any period of 180
consecutive days during the term hereof; provided, however, that disability
shall not constitute a basis for discharge for cause;

            3.2.3 The discharge of Employee by Bank for cause. "Cause" as used
herein shall mean (i) Employee's gross negligence or willful misconduct as shall
constitute, as a matter of law, a breach of the covenants and obligations of
Employee hereunder; (ii) failure or refusal of Employee to comply with the
provisions of the Agreement; (iii) Employee's conviction by any duly constituted
court with competent jurisdiction of a crime (other than traffic offenses); (iv)
Employee's malfeasance or incompetence, provided that in applying this criteria
Bank shall not be unreasonable or arbitrary, and provided further that prior to
effecting a dismissal under this Section (iv) Bank shall afford Employee with
fair and reasonable warning and with a fair and reasonable opportunity to cure
any defects in Employee's performance.

      3.3 TERMINATION BY EMPLOYEE. Employee may terminate his employment with
Bank with or without cause by giving thirty (30) days written notice of
termination. "Cause" as used herein shall include Bank's failure or refusal to
comply with the provisions of the Agreement.

      3.4 EFFECT OF TERMINATION. The termination of Employee's employment shall
constitute a tender by Employee of his resignation as an officer of Bank, and as
a member of any board of directors or board committees of Bancorp or its
affiliates if Employee is a member thereof at the time of termination.

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      3.5 PAYMENT ON TERMINATION. If Employee's employment is terminated by
Employee with or without cause, or by Bank with or without cause, Employee shall
be paid all base salary and benefits accrued under the Agreement as of the
termination date.

        3.6 SEVERANCE PAYMENT. If Employee's employment is terminated by
Employee with cause, or by Bank without cause, Employee shall be paid all base
salary and benefits accrued under the Agreement as of the termination date, and
in addition, shall be entitled to a severance payment equal to the lesser of (i)
four month's base salary as of the date of termination multiplied by the number
of full calendar years Employee has been employed by Bank or any predecessor
thereof, or (ii) one month's base salary as of the date of termination
multiplied by twenty-four (24). For purposes of Section 3.6(i) a period of
continuous full-time employment for six months or more in a calendar year shall
count as a full calendar year. If for any period Employee has been employed
simultaneously by Bank and by one or more of its affiliates, such period shall
count only once in determining the severance payment under Section 3.6(i). The
severance payment provided herein shall be paid in full within thirty (30) days
of the date of Employee's termination. Employee shall not be entitled to such
severance payment if Employee's employment is terminated by Bank with cause, or
by Employee without cause, and in either such case, Employee shall only be
entitled to receive on termination a payment equal to Employee's base salary and
benefits accrued under the Agreement as of the termination date, and no other
payments.

        3.7 PERFORMANCE BONUS. If Employee's employment is terminated by
Employee with cause, or by Bank without cause, Employee shall be paid, in
addition to the amounts payable under Sections 3.5 and 3.6 of the Agreement: (i)
all non-forfeitable deferred compensation, if any; and (ii) unpaid performance
bonus payments, if any, payable under Section 4.2 of the Agreement, which shall
be declared earned and payable based upon performance up to, and shall be
pro-rated as of, the date of termination. Employee shall not be entitled to such
unpaid performance bonus payments if Employee's employment is terminated by Bank
with cause, or by Employee without cause.

      4. COMPENSATION.

      4.1 BASE SALARY. For the period beginning April 15, 2006 and ending April
14, 2007, Employee shall be paid an annual base salary of $121,000.00, payable
in equal bimonthly installments and subject to any deductions required by law.
Base salary for the remainder of 2007 shall be determined by Bank prior to April
14, 2007. The base salary will increased effective August 1, 2006 through April
14, 2007 to an annualized rate of $126,000 payable as shown above.

      4.2 PERFORMANCE BONUS. Employee shall be entitled to consideration for
annual performance bonus compensation for each calendar year constituting a
percentage

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of annual base salary earned from his employment by Bank during such calendar
year. Bonus compensation shall be subject to any deductions required by law. The
Bank or Bancorp Board shall timely, and at least once yearly, determine the
amount of and the formulas and methods for establishing such bonus compensation.
The amount of such bonus compensation shall at all times be discretionary, and
Bank may decline to award a performance bonus to Employee in any year.

            4.2.1 Employee shall be entitled to a pro-rata performance bonus for
less than a full year of performance if Employee's employment is terminated by
Employee with cause, or by the Bank without cause (including termination
following a change of control as described in Section 7.4 of the Agreement),
prior to the date on which Employee would otherwise be entitled to consideration
for Employee's annual performance bonus. In such circumstances, such pro-rata
performance bonus shall be declared earned and payable as of the date of
termination.

      5. BENEFITS; PURCHASE OF SHARES.

      5.1 ELIGIBILITY FOR GENERAL BENEFITS. Employee shall be eligible to
participate in any plan of Bank or its affiliates relating to stock options,
stock purchases, profit sharing, group life insurance, medical coverage,
education and other retirement or employee benefits that Bank or its affiliates
may adopt for the benefit of employees.

      5.2 CAR ALLOWANCE. Employee shall receive no car allowance.

      5.3 ADDITIONAL BENEFITS. Employee shall be eligible to participate in any
other benefits which may be or become applicable to Bank's executive employees
of similar rank. In addition, Employee shall be entitled to: (i) a reasonable
expense account for use in connection with Bank business; and (ii) any other
benefits which in Bank's judgment are commensurate with the responsibilities and
functions to be performed by Employee under the Agreement, including the payment
of reasonable expenses for attendance by Employee and Employee's spouse at
annual meetings of the Oregon Bankers Association.

      5.4 SHARE OWNERSHIP. During the term of the Agreement, including
extensions, Employee shall purchase shares of Bancorp Stock, including purchases
through the exercise of stock options, in accordance with the share ownership
policies and requirements established by Bancorp or Bank management in effect
from time to time for employees of comparable rank.

      6. VACATIONS AND LEAVES.

      6.1 PAID VACATION. During the term of the Agreement, Employee shall be
entitled to annual paid vacation benefits identical to those offered to
employees of Bank holding executive vice president or higher positions. The
timing of vacations shall be scheduled in a reasonable manner by Employee.
Employee shall not be entitled to receive any additional compensation from Bank
on account of his failure to take a

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vacation, and may not accumulate unused vacation time from one calendar year to
the next.

      6.2 LEAVES WITH OR WITHOUT PAY. The Bank Board may grant Employee a leave
or leaves of absence, with or without pay, at such time or times and upon such
terms and conditions as the Board may determine.

      6.3 MANDATORY ABSENCE. In each calendar year Employee shall be absent from
Bank for one period of two consecutive weeks. Such period may include vacation,
leave, sick leave, attendance at seminars or conventions, or any combination
thereof.

      7. CHANGE OF CONTROL.

      7.1 SURVIVAL OF RIGHTS. Employee's rights on termination of employment
under Section 3 of the Agreement, as well as all other rights of Employee under
the Agreement or applicable law, shall survive a change of control of Bancorp or
Bank whether or not Employee opposed or favored the change of control.

      7.2 RIGHTS ON CHANGE OF CONTROL. If a change of control of Bancorp or Bank
occurs while the Agreement is in effect, Employee shall have ninety (90) days
following the date such change of control becomes effective to elect to
terminate Employee's employment with cause. If Employee so elects to terminate,
such termination shall constitute a termination by Employee with cause, and
Employee shall receive all payments and benefits due to Employee on termination
by Employee with cause under Section 3 of the Agreement. Notwithstanding the
foregoing, if following such change of control Employee is offered a position of
employment either substantially equivalent to Employee's compensation and
position prior to the change of control, or an executive officer position with
significant responsibility and compensation commensurate (and substantially
equivalent to his previous compensation) with such responsibility, and Employee
elects nevertheless to termination, Employee's employment under this Section
7.2,Employee shall be entitled to a maximum severance payment under Section 3.6
equal to one month's base salary as of the date of termination multiplied by
nine (9).

      7.3 BASE COMPENSATION. Following a change of control, Bank shall not
reduce Employee's base compensation in effect prior to the effective date of the
change of control for a period of time equal to the greater of (i) twenty four
(24) months from the effective date of the change of control; (ii) one (1) month
for each full calendar year Employee has been employed by Bank; or (iii) the
remaining term of the Agreement, including any extensions thereof. For purposes
of this Subsection 7.3, a period of continuous full-time employment for six
months or more in a calendar year shall count as a full calendar year.

      7.4 TERMINATION WITHOUT CAUSE. If following a change of control Bank
terminates Employee's employment within two (2) years of the effective date of
the change of control because of a reduction in force or for any other reason,
other than for cause pursuant to Section 3.3 of the Agreement, such termination
shall constitute a

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termination by Bank without cause, and Employee shall receive all payments and
benefits due to Employee on termination under Sections 3.5 and 3.6 of the
Agreement, plus: (i) all non-forfeitable deferred compensation, if any; and (ii)
unpaid performance bonus payments, if any, payable under Section 4.2 of the
Agreement, which shall be declared earned and payable based upon performance up
to, and shall be pro-rated as of, the date of termination.

      7.5 OPTIONS AND STOCK. If Employee is a participant in a restricted stock
plan or share option plan, and such plan is terminated involuntarily as a result
of the change of control, all stock and options shall be declared fully vested
and shall be paid, awarded or otherwise distributed. With respect to any
unexercised options under any stock option plan, such options may be exercised
within the period provided in such plan. Effective as of the date of the change
of control, any holding period established for stock paid as bonus or other
compensation shall be deemed terminated, except as otherwise provided by law.

      7.6 RELOCATION. If relocation is required by the acquiring institution the
relocation package option will be at the choice of the Employee. He/she may pick
Columbia's relocation package at the time of the merger or the package offered
by the acquiring company. This option is available for one year from the merger
date.

      7.7 DEFINITION. As used in this Section, "control" shall mean the
acquisition during Employee's employment of twenty-five percent (25%) or more of
the voting securities of Bancorp or Bank by any person, or persons acting as a
group within the meaning of Section 13(d) of the Securities Exchange Act of
1934, or to such acquisition of a percentage between ten percent (10%) and
twenty-five percent (25%) if the Board or the Comptroller of the Currency, the
FDIC, or the Federal Reserve Bank have made a determination that such
acquisition constitutes or will constitute control of Bancorp or Bank. The term
"person" refers to an individual, corporation, bank, bank holding company, or
other entity, but excludes any Employee Stock Ownership Plan established for the
benefit of employees of Bancorp or any of its subsidiaries or other affiliates.

      8. POST TERMINATION COVENANTS.

      8.1 NON-COMPETE COVENANTS. If Employee terminates his employment without
cause, or if Employee's employment is terminated by Bank for cause, then for one
year from the date of such termination Employee will not, without the prior
written consent of Bank:

            8.1.1 Undertake full or part-time work, either as an employee or as
a consultant, for another financial institution if such work is to be done, in
whole or in part, in or from an office or other work site in Yamhill, Wasco,
Hood River, Jefferson, Deschutes, Sherman or Gilliam Counties, Oregon, in
Klickitat County, Washington, or in any other county in Oregon or Washington in
which Bancorp or any of its affiliates has a place of business at the time of
termination; or

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            8.1.2 Hire for any financial institution or other employer
(including himself) any employee of Bancorp or any of its affiliates, or
directly or indirectly cause such an employee to leave his or her employment to
work for another employer, if such employee is to work in or from an office or
other work site in Yamhill, Wasco, Hood River, Jefferson, Deschutes, Sherman or
Gilliam Counties, Oregon, in Klickitat County, Washington, or in any other
county in Oregon or Washington in which Bancorp or any of its affiliates has a
place of business at the time of termination.

      8.2 LIQUIDATED DAMAGES FOR BREACH OF NON-COMPETE COVENANTS; OTHER
REMEDIES. If Employee breaches the covenants of Section 8.1, Employee shall be
liable to Bank for liquidated damages equal to the lesser of (i) $18,000, or
(ii) $1,500 multiplied by the number of months (including fractions thereof)
between the date of breach and one year from the date of Employee's termination
of employment. For example, if the date of breach occurs six months after the
date of Employee's termination, liquidated damages shall be $9,000 (6 x $1,500).
The parties agree that Bank's actual money damages upon Employee's breach will
be difficult to compute, and further agree that the liquidated damages formula
provided herein reasonably represents Bank's actual money damages. Employee
shall pay the liquidated damages required hereunder within ten (10) days of the
date Bank makes written demand for such payment. Nothing herein shall preclude
Bank from enforcing any other legal or equitable remedies it may have upon
Employee's breach, including injunctive relief. Such other remedies may be
enforced in addition to Bank's right to liquidated damages under this Section.

      8.3 LIMITATION. The covenants in Sections 8.1 and 8.2 do not apply if
Employee terminates his employment for cause, if Employee terminates his
employment for any reason within ninety (90) days after the effective date of a
change of control within the meaning of Section 7 of the Agreement, or if
Employee's employment is terminated by Bank without cause.

      8.4 ADDITIONAL COVENANTS. The following provisions shall apply and be
binding on Employee following Employee's termination of employment under all
circumstances, whether termination occurred with cause, without cause, following
illness or disability, because of a change of control, or for any other reason:

            8.4.1 Employee shall fully cooperate in the defense or prosecution
of any litigation arising from or relating to matters about which Employee has
knowledge based on his employment or other work, paid or unpaid, for Bank and
its affiliates. To the extent allowed by law Employee shall receive reasonable
compensation in connection with his performance under this Section 8.4.1;

            8.4.2 Employee shall at all times keep all confidential and
proprietary information gained from his employment by Bank, or from other
previous, present or subsequent paid or unpaid work for Bank and its affiliates,
in strictest confidence, and will not disclose or otherwise disseminate such
information to anyone, other than to employees of Bank or its affiliates, except
as may be required by law, regulation or subpoena; and

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            8.4.3 Employee shall not take or use for any purpose confidential or
proprietary information of Bank or its affiliates, including without limitation
customer or potential customer lists and trade secrets.

      8.5 ADVANCEMENT OF EMPLOYEE. Employee acknowledges and agrees that the
Agreement constitutes a bona fide advancement of Employee with the Employer
under ORS 653.295 in several respects, including without limitation an increase
in base salary and benefits.

      9. MISCELLANEOUS.

      9.1 RECITALS; LAW; AMENDMENTS. Each and every portion of the Agreement is
contractual and not a mere recital, and all recitals shall be deemed
incorporated into the Agreement. The Agreement shall be governed by and
interpreted according to Oregon law and any applicable federal law. The
Agreement may not be amended except by a subsequent written agreement signed by
all parties hereto.

      9.2 ENTIRE AGREEMENT. The Agreement contains the entire understanding and
agreement of the parties with respect to the parties' relationship, and all
prior negotiations, discussions or understandings, oral or written, are hereby
integrated herein. No prior negotiations, discussions or agreements not
contained herein or in such documents shall be binding or enforceable against
the parties.

      9.3 COUNTERPARTS. The Agreement may be signed in several counterparts. The
signature of one party on any counterpart shall bind such party just as if all
parties had signed that counterpart. Each counterpart shall be considered an
original. All counterparts of the Agreement shall together constitute one
original document.

      9.4 SUCCESSORS AND ASSIGNS. All rights and duties of Bank under the
Agreement shall be binding on and inure to the benefit of Bank's successors and
assigns, including any person or entity which acquires a controlling interest in
Bank and any person or entity which acquires all or substantially all of Bank's
assets. Bank and any such successor or assign shall be and remain jointly and
severally liable to Employee under the Agreement. Employee may not assign or
transfer Employee's rights or interests in or under the Agreement other than by
a will or by the laws of descent and distribution. The Agreement shall inure to
the benefit of and be enforceable by Employee's estate or legal representative.

      9.5 WAIVER. Any waiver by any party hereto of any provision of the
Agreement, or of any breach thereof, shall not constitute a waiver of any other
provision or of any other breach. If any provision, paragraph or subparagraph
herein shall be deemed invalid, illegal or unenforceable in any respect, the
validity and enforceability of the remaining provisions, paragraphs and
subparagraphs shall not be affected.

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      9.6 ARBITRATION. Any dispute, controversy, claim or difference concerning
or arising from the Agreement or the rights or performance of either party under
the Agreement, including disputes about the interpretation or construction of
the Agreement, shall be settled through binding arbitration in the State of
Oregon and in accordance with the rules of the American Arbitration Association.
A judgment upon the award rendered in such arbitration may be entered in any
court of competent jurisdiction.

      9.7 EMPLOYEE HANDBOOK. Employee agrees to be bound by the terms and
conditions of any employee handbook of Bank or its affiliates as may be in
effect from time to time, except that in the event of a conflict between such
employee handbook and the Agreement, the Agreement shall control.

      9.8 CAPTIONS. All captions, titles and headings in the Agreement are for
convenience only, and shall not be construed to limit any term of the Agreement.

      9.9 DEFINITION. When used herein in reference to a corporation,
"affiliate" shall mean, without limitation, any parent or subsidiary of the
corporation and any entity controlled by the corporation.

      9.10 EXCEPTIONS. The Bank Board or the management of Bank may, in its
discretion, make exceptions to one or more of the conditions contained in the
Agreement, provided that any such exceptions must be approved in writing.

      9.11 PRIOR CONTRACTS. The Agreement replaces and supersedes all prior
written employment agreements and amendments thereof between the parties.

/s/ Britt W. Thomas
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Employee

Date: August 1, 2006

COLUMBIA RIVER BANK

By: /s/ Roger L. Christensen
    -----------------------------------
Title: Chief Executive Officer

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