<PAGE>

                                                                   EXHIBIT 10.7b

                    SECOND AMENDMENT TO EMPLOYMENT AGREEMENT

     THIS SECOND AMENDMENT, effective April 30, 2002 between COLUMBIA BANCORP, a
Maryland corporation (the "Corporation"), THE COLUMBIA BANK, a Maryland trust
company and a principal subsidiary of the Corporation (the "Bank"), and JOHN M.
BOND, JR. (the "Executive"), amends the Employment Agreement between the
Corporation, the Bank and the Executive, dated February 26, 1996, as amended
December 18, 1997 (the "Employment Agreement").

                              W I T N E S S E T H:

     The Corporation and the Bank (each, a "Company" and collectively, the
"Companies") recognized the Executive's contribution to the organization, growth
and success of the Companies and entered into the Employment Agreement with the
Executive to secure his services. The Companies and the Executive desire to
amend the Employment Agreement as set forth below in this Second Amendment to
provide for the extension of health benefits for a period of ten years upon a
change in control.

     Accordingly, in consideration of the mutual covenants and representations
contained herein and the mutual benefits derived herefrom, the Companies and the
Executive agree to amend the Employment Agreement as follows:

     1. Paragraph 5.2 shall be amended to read as follows:

          "5.2.     Amount of Payments. Except as provided in paragraph 5.2(e),
     and in lieu of amounts payable under paragraph 4, the Companies will pay
     the Executive the following amounts in the following circumstances:

          (a) (i)   If the Executive is terminated by either of the Companies in
        the circumstances described under paragraph 4.3(a)(i), or if the
        Executive resigns during a Change in Control Period in the circumstances
        described under paragraph 4.3(a)(ii), or if during a Change in Control
        Period the Executive resigns in circumstances other than those described
        under paragraph 4.3(a)(ii) without having been offered an employment
        agreement the terms of which are comparable to those of this Agreement,
        the Companies will pay, or cause to be paid, to the Executive: (a) if
        the Executive's termination or resignation occurs before the Executive
        has attained the age of 62 years, an amount equal to three times the sum
        of (i) the Executive's annual base salary immediately before the Change
        in Control and (ii) the average of the bonuses paid to the Executive
        over the past three years (including years in which no bonus was
        awarded); or (b) if the Executive's termination or resignation occurs on
        or after the Executive has attained the age of 62 years, an amount equal
        to the amount set forth in paragraph 5.2(a)(i)(a) multiplied by a
        fraction, the numerator of which

<PAGE>

        shall be 1,095 minus the number of days which have passed since the
        Executive's 62nd birthday, and the denominator of which shall be 1,095.

              (ii)  Such payment shall be made in one lump sum within 15
        business days after the Executive's termination or resignation.

          (b) (i)   If the Executive resigns during a Change in Control Period
        in circumstances other than those described under paragraph 4.3(a)(ii)
        after having been offered an employment agreement the terms of which are
        comparable to those of this Agreement, the Companies will pay, or cause
        to be paid, to the Executive: (a) if the Executive's resignation occurs
        before the Executive has attained the age of 64 years, an amount equal
        to the sum of (i) the Executive's annual base salary immediately before
        the Change in Control and (ii) the average of the bonuses paid to the
        Executive over the past three years (including years in which no bonus
        was awarded); or (b) if the Executive's resignation occurs on or after
        the Executive has attained the age of 64 years, an amount equal to the
        amount set forth in paragraph 5.2(b)(i)(a) multiplied by a fraction, the
        numerator of which shall be 365 minus the number of days which have
        passed since the Executive's 64th birthday, and the denominator of which
        shall be 365.

              (ii)  Such payment shall be made in one lump sum within 15
        business days after the Executive's resignation.

          (c) Except as provided in paragraph 5.2(e), if the Executive is
        terminated by the Companies or resigns as described in paragraph 5.2(a),
        or resigns as described in paragraph 5.2(b), the Executive shall
        continue to receive all health, life, and disability insurance benefits
        available to him pursuant to paragraph 1.2(b) of this Agreement that he
        was receiving immediately before such termination or resignation. The
        Executive shall pay the same percentage of the total cost of such
        coverage as he was paying when his employment terminated. The total cost
        of the Executive's continued coverage shall be determined using the same
        rates for health, life and/or disability coverage that apply from time
        to time to similarly situated active employees. The Executive shall
        continue to receive such benefits until the earliest of (i) such time as
        the Executive shall have been receiving substantially similar insurance
        benefits for six months under subsequent employment, (ii) in the case of
        life and disability benefits, 36 months after the date of a termination
        or resignation described in paragraph 5.2(a) or 12 months after the date
        of a resignation described in paragraph 5.2(b), (iii) in the case of
        health benefits, 10 years after the

                                        2

<PAGE>

        date of termination or resignation described in paragraph 5.2(a) or 12
        months after the date of resignation described in paragraph 5.2(b), or
        (iv) such date as the Executive shall have attained the age of 65 years.

          (d) All options granted to the Executive under the Corporation's stock
        option award arrangements providing for the granting of options to
        acquire common stock to founders, directors and key employees shall
        immediately become fully vested in the event of a Change in Control.

          (e) The Executive is to receive no payments under paragraph 5.2(a) or
        (b) and no benefits under paragraph 5.2(c) if the Executive is
        terminated during a Change in Control Period after having already
        attained the age of 65 years, or if the Executive is terminated by
        either of the Companies during a Change in Control Period upon the death
        or total disability of the Executive or for cause. In an instance of
        death or total disability of the Executive, however, the Executive and
        his dependents, beneficiaries and estate shall receive any benefits
        payable to them under paragraphs 4.2 (c) and 4.2 (d).

          (f) (i)   The Executive shall bear all expense of, and be solely
        responsible for, all federal, state, or local taxes due with respect to
        any payment received hereunder, including, without limitation, any
        excise tax imposed by Section 4999 of the Internal Revenue Code of 1986,
        as amended (the "Code"); provided, however, that any payment or benefit
        received or to be received by the Executive in connection with a Change
        in Control or the termination of the Executive's employment (whether
        payable pursuant to the terms of this Agreement ("Contract Payments") or
        any other plan, arrangements or agreement with the Companies or any
        affiliate (collectively with the Contract Payments, the "Total
        Payments") shall be reduced to the extent necessary so that no portion
        thereof shall be subject to the excise tax imposed by Section 4999 of
        the Code but only if, by reason of such reduction, the net after-tax
        benefit received by the Executive shall exceed the net after-tax benefit
        received by the Executive if no such reduction was made.

              (ii)  For purposes of this paragraph 5.2(f), "net after-tax
        benefit" shall mean (i) the total of all payments and the value of all
        benefits which the Executive receives or is then entitled to receive
        from the Companies that would constitute "parachute payments" within the
        meaning of Section 280G of the Code, less (ii) the amount of all
        federal, state and local income taxes payable with respect to the
        foregoing calculated at the maximum marginal income tax rate for each
        year in which the foregoing shall be paid to the Executive (based

                                        3

<PAGE>

        on the rate in effect for such year as set forth in the Code as in
        effect at the time of the first payment of the foregoing), less (iii)
        the amount of excise taxes imposed with respect to the payments and
        benefits described in (i) above by Section 4999 of the Code.

              (iii) The foregoing determination shall be made by a nationally
        recognized accounting firm (the "Accounting Firm") selected by the
        Companies and reasonably acceptable to the Executive (which may be, but
        will not be required to be, the Companies' independent auditors). The
        Accounting Firm shall submit its determination and detailed supporting
        calculations to both the Executive and the Companies within fifteen (15)
        days after receipt of a notice from either of the Companies or from the
        Executive that the Executive may receive payments which may be
        "parachute payments." If the Accounting Firm determines that such
        reduction is required by this paragraph 5.2(f), the Executive, in the
        Executive's sole and absolute discretion, may determine which Total
        Payments shall be reduced or forfeited to the extent necessary so that
        no portion thereof shall be subject to the excise tax imposed by Section
        4999 of the Code, and the Companies shall pay such reduced amount to the
        Executive. If the Accounting Firm determines that no reduction or
        forfeiture is necessary under this paragraph 5.2(f), it will, at the
        same time as it makes such determination, furnish the Executive and the
        Companies an opinion that Executive shall not be liable for any excise
        tax under Section 4999 of the Code. The Executive and the Companies
        shall each provide the Accounting Firm access to and copies of any
        books, records, and documents in the possession of the Executive or the
        Companies, as the case may be, reasonably requested by the Accounting
        Firm, and otherwise cooperate with the Accounting Firm in connection
        with the preparation and issuance of the determinations and calculations
        contemplated by this paragraph 5.2(f). The fees and expenses of the
        Accounting Firm for its services in connection with the determinations
        and calculations contemplated by this paragraph 5.2(f) shall be borne by
        the Companies.

                                        4

<PAGE>

     IN WITNESS WHEREOF, the parties have executed and delivered this Second
Amendment to the Employment Agreement on this 30 day of April, 2002.

ATTEST:                                 COLUMBIA BANCORP

                                        /s/ John A. Scaldara, Jr.
-----------------------------           ----------------------------
                                        John A. Scaldara, Jr.
                                        Executive Vice President and
                                        Chief Financial Officer

ATTEST:                                 THE COLUMBIA BANK

                                        /s/ John A. Scaldara, Jr.
-----------------------------           ----------------------------
                                        John A. Scaldara, Jr.
                                        Executive Vice President and
                                        Chief Financial Officer

WITNESS:

                                        /s/ John M. Bond, Jr.
-----------------------------           ----------------------------
                                        John M. Bond, Jr.

                                        5