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                                                                    EXHIBIT 10.1

                               BADGER METER, INC.

                           EXECUTIVE SUPPLEMENTAL PLAN
                                FOR KEY EMPLOYEES

                           (EFFECTIVE JANUARY 1, 2005)

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                                TABLE OF CONTENTS

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<S>          <C>                                                            <C>
SECTION 1.   ESTABLISHMENT OF PLAN AND PURPOSE                                1

SECTION 2.   DEFINITIONS AND CONSTRUCTION                                     1

SECTION 3.   ELIGIBILITY                                                      2

SECTION 4.   CREDITED AMOUNTS AND MEMORANDUM ACCOUNT                          2

SECTION 5.   BENEFIT DISTRIBUTIONS                                            3

SECTION 6.   FUNDING                                                          4

SECTION 7.   ADMINISTRATIVE PROVISIONS                                        4

SECTION 8.   GENERAL PROVISIONS                                               5
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                               BADGER METER, INC.

                  EXECUTIVE SUPPLEMENTAL PLAN FOR KEY EMPLOYEES

     Establishment of Plan and Purpose

          Establishment of Plan. Badger Meter, Inc. hereby establishes the
          "Badger Meter, Inc. Executive Supplemental Plan For Key Employees"
          effective January 1, 2005 (the "Plan").

          Purpose of the Plan. The Plan has been established to supplement the
          benefits that eligible Participants will receive under the Company's
          qualified retirement plans. Section 401(a)(17) of the Internal Revenue
          Code of 1986, as amended (the "Code"), limits the amount of
          compensation which can be considered in determining benefits under a
          qualified retirement plan. Because of this rule, the Company cannot
          contribute the same percentage of compensation on behalf of the
          Participants that it can contribute on behalf of other employees. As a
          result, the Company makes a limited contribution to its qualified
          retirement plans on behalf of the Participants. The Company intends to
          supplement the Participants' benefits under the Company's qualified
          retirement plans by providing a supplemental benefit as determined
          under the terms of this Plan.

     Definitions and Construction

          Definitions.

               Code. The Internal Revenue Code of 1986, as amended.

               Company. Badger Meter, Inc., a Wisconsin corporation, and any
               successor. The Board of Directors of the Company, or those board
               members authorized by the entire Board of Directors, shall act on
               behalf of the Company for purposes of the Plan.

               Compensation. A Participant's annual base pay from the Company.

               Employment. Employment within the Company.

               ERISA. The Employee Retirement Income Security Act of 1974, as
               amended.

               Memorandum Account. The account maintained for the Participant
               pursuant to Section 4 below.

               Normal Retirement. Termination of employment with the Company on
               or after the date the Participant attains age 65.

               Participant. Each member of the Company's Executive Committee who
               is approved for participation in the Plan by the Corporate
               Governance Committee of the Company's Board of Directors.

               Plan. The Badger Meter Executive Supplemental Plan For Key
               Employees, as

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               stated in this document and as amended from time to time.

               Plan Year. Each calendar year.

          Construction. The laws of the State of Wisconsin, as amended from time
          to time, shall govern the construction and application of this Plan,
          except to the extent that federal law preempts state law. All
          references to statutory sections shall include the sections as amended
          from time to time or any other statute of similar meaning. If state
          law, federal law or regulatory provisions render any provision of this
          Plan unenforceable, the Plan provision shall have no effect to the
          extent required by law or regulation.

     Eligibility

          Commencement of Participation. Each eligible Participant shall
          participate in this Plan on the date specified by the Corporate
          Governance Committee of the Company's Board of Directors.

          Termination of Participation. The Participant's right to participate
          in this Plan shall cease on the earlier of: (a) the date his
          Employment terminates; (b) the date the Company terminates the Plan;
          or (c) the date the Company removes the Participant from continued
          participation.

     Credited Amounts and Memorandum Account

          Credited Contributions. As of the last day of each month prior to a
          Participant's termination of Employment, the Company shall make a
          contribution to the Plan on behalf of such Participant in an amount
          equal to 7.5% of the Participant's Compensation for that month.

          Credited Earnings

               As of the last day of each month prior to complete distribution
               of a Participant's Memorandum Account, the total amount credited
               to and remaining in the Participant's Memorandum Account relating
               to prior years' contributions and interest shall be credited with
               interest.

               Interest shall be credited at a rate equal to the prime rate of
               interest in effect at the M&I Marshall & Ilsley Bank of
               Milwaukee, Wisconsin (or the Company's prime lender, if not the
               M&I) as of the first business day of each Plan Year.

          Memorandum Account.

               Solely for the purpose of measuring the total amount due to the
               Participant, the Company shall maintain a Memorandum Account. The
               Company shall use the Memorandum Account to keep records to
               determine the credited contribution and credited earnings for
               each Plan Year. Within 30 days after the last day of each Plan
               Year, the Company shall


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               provide to the Participant, his beneficiary or estate, a
               statement indicating the balance credited to the Memorandum
               Account.

               The Memorandum Account shall not represent specific investments
               or other assets of the Company even if the Company has purchased
               insurance or accumulates funds for the purpose of paying the
               Participant under this Plan. The Memorandum Account shall not
               constitute or be treated for any reason as a trust for, property
               of, or a security interest for the benefit of, the Participant,
               his beneficiary or estate. The Participant's rights under this
               Plan are limited to those of a general unsecured creditor of the
               Company; the Plan constitutes a mere promise by the Company to
               make benefit payments in the future.

     Benefit Distributions

          General. As described in Sections 5.2 and 5.3, the amount payable to
          the Participant at Normal Retirement or other termination of
          Employment shall be determined by the amount, including earnings,
          credited to his Memorandum Account.

          Normal Retirement Benefit. Upon Normal Retirement, the Company will
          pay the Participant's accrued benefit in either of the following two
          methods, as elected by the Participant in accordance with Section 5.6.

          A single lump sum paid on the first business day of the 7th month
          following his Normal Retirement date; or

               Payments over 10 or fewer years as selected by the Participant,
               payable in quarterly installment payments beginning on the first
               business day of the 7th month following the date of the
               Participant's Normal Retirement. The Company shall determine the
               amount of each installment payment using the "declining digits"
               method. The first year's payments are based on 1/10 of the then
               current balance and the second year's installments are based on
               1/9 of the then current balance, and so on. The unpaid balance
               shall be credited with interest as provided in Section 4.2.

          Benefit Upon Other Termination of Employment. Upon death, disability,
          or any other termination of employment before Normal Retirement, the
          Company will pay the accrued benefit to the Participant or beneficiary
          in the form of a lump sum on the first business day of the 7th month
          following the date of the Participant's termination of employment.

          Hardship Distribution. Notwithstanding the provisions in this Section
          5, in the event of a financial emergency occurring in the personal
          affairs of the Participant or beneficiary during the payout period,
          the Plan Administrator may in its sole discretion elect to accelerate
          the payout. The term "unforeseeable emergency" means a severe
          financial hardship to the Participant resulting from an illness or
          accident of the Participant, the Participant's spouse, or a dependent
          (as defined in Section 152 of the Internal Revenue Code) of the
          Participant, loss of the


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          Participant's property due to casualty, or other similar extraordinary
          and unforeseeable circumstances arising as a result of events beyond
          the control of the Participant. The amount distributed with respect to
          an emergency may not exceed the amount necessary to satisfy such
          emergency plus the amount necessary to pay taxes reasonably
          anticipated as a result of the distribution, after taking into account
          the extent to which such hardship is or may be relieved through
          reimbursement or compensation by insurance or otherwise or by
          liquidation of the Participant's assets (to the extent the liquidation
          of such assets would not itself cause severe financial hardship).

          Designation of Beneficiary. The Participant shall have the right to
          designate a beneficiary or beneficiaries to receive any portion of his
          Memorandum Account unpaid at his death. Such designation shall be
          effected by filing written notification with the Plan Administrator in
          the form it prescribes and may be changed from time to time by similar
          action. If the Participant does not make such designation, any such
          unpaid portion of the Participant's benefit shall be paid to his
          estate in accordance with whatever plan may be selected by the Plan
          Administrator.

          Payment Election. A Participant's election shall be filed with the
          Plan Administrator at the time he or she begins participation in the
          Plan on a form designated by the Plan Administrator. The election
          shall specify the form of distribution desired when distribution
          becomes available. An election may only be changed with respect to
          amounts earned in calendar years following the date the election
          change is filed with the Plan Administrator. The Participant may not
          change this election with respect to amounts previously contributed to
          the Plan. The Company shall establish separate subaccounts as needed
          to identify amounts subject to different payment elections.

     Funding

          The Company intends that the arrangement described in this Plan be
unfunded for tax purposes and for purposes of Title I of ERISA. All benefits
payable pursuant to the Plan shall be paid for, or provided by, the Company from
its general assets. If the Company establishes a trust to assist the Company in
providing benefits under this Plan, the trust will conform to the terms of the
model trust as described in Revenue Procedure 92-64 or, if applicable,
subsequent regulatory guidance.

     Administrative Provisions

          Administrator. The Company is the administrator of the Plan and
          determines the amount and character of all Plan benefits. The Company
          has the authority and discretion to interpret the Plan, to promulgate
          and revise rules pertaining to the Plan, and to make any other
          determination which it deems necessary or advisable for the
          administration of the Plan. The Company's decisions with respect to
          the Plan are final.

          Administrative Duties. With the exception of the duties specified in
          Section 7.3, the Company may delegate its duties to any officer,
          employee or advisory committee. However, the Participant may not, in
          any event or circumstance,


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          exercise discretion or control on behalf of the Company with respect
          to his own Plan benefits. As of the effective date of this Plan, the
          Company has delegated its administrative duties to the non-Participant
          members of the Badger Meter, Inc. Corporate Governance Committee. The
          Company may remove such persons and appoint replacements as it
          determines appropriate.

          Termination and Amendment. The Company, by written resolution of its
          Board of Directors, may terminate, suspend, alter or amend this Plan
          at any time. The Participant shall be vested in his Memorandum Account
          as of the date that the Plan is terminated, suspended, altered or
          amended and the amount provided under the Plan shall continue to be
          paid to the Participant, his beneficiary or estate as provided under
          this Plan. (No amendment may deprive a Participant of a benefit
          accrued prior to the amendment, including earnings credited to the
          account balance, without the Participant's consent.)

     General Provisions

          No Pledge. No person eligible to receive any payment under this Plan
          shall have the right to pledge, assign, transfer, sell, or otherwise
          dispose of all or any portion of such payment, either directly or by
          operation of law, including, but not by way of limitation, execution,
          levy, garnishment, attachment, pledge or bankruptcy.

          Continued Employment. Nothing in this Plan shall be construed or
          interpreted as giving the Participant the right to be retained by the
          Company or impair the Company's right to terminate his services.

          Forfeiture for Cause. If a Participant's Employment is terminated for
          Cause, his benefits under this Plan shall be fully and completely
          forfeited. "Cause" means, as determined by the Company, the
          Participant's intentional dishonest or illegal conduct in connection
          with his performance of services for the Company.

          Successors. This Plan shall inure to the benefit of and shall be
          enforceable by the Company, its successors and assigns.

          Withholding. The Company has the right to deduct any federal, state or
          local taxes required by law to be withheld from any payment under this
          Plan.

          Notice. All notices, designations or reports provided for in this Plan
          shall be in writing and delivered personally or by registered or
          certified mail, return receipt requested. In the case of the Company,
          correspondence shall be addressed to the Company's principal business
          office. In the case of the Participant or his beneficiary,
          correspondence shall be addressed to his or his beneficiary's home
          address as shown on the records of the Company.


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          Indemnification. The Company shall indemnify each individual who is
          responsible for administering the Plan against all claims, losses,
          damages, and expenses, including counsel fees, incurred by such
          individual and any liability, including any amounts paid in settlement
          with the Company's approval arising from the individual's actions or
          failure to act, except when the act or omission is judicially
          determined to be misconduct or willful misconduct of the individual.


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                               BADGER METER. INC.

                           EXECUTIVE SUPPLEMENTAL PLAN
                                FOR KEY EMPLOYEES

                             BENEFICIARY DESIGNATION
                            AND PAYMENT ELECTION FORM

          I hereby elect that the amount due me upon Normal Retirement, if any,
under the Executive Committee Supplemental Employee Retirement Plan relating to
amounts earned in calendar years beginning on or after ___________________ be
paid to me:

               [ ]  In one lump sum

               [ ]  In quarterly installments (must be a multiple of 4 and no
                    more than 40)

          I hereby designate as my beneficiary or beneficiaries pursuant to
Section 5.5 of the Plan:

________________________________________________________________________________

________________________________________________________________________________

          I reserve the right to revoke and/or change this election form as to
amounts earned in calendar years after the filing of a new form and as delivered
provided under the terms and conditions of said Plan.


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Date

Received by the Plan Administrator for the Badger Meter Executive Supplemental
Plan For Key Employees on ________________, 20__.


                                        By:
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