<PAGE>

                                                                   EXHIBIT 10(f)

                                   TIDEWATER

                          SECOND AMENDED AND RESTATED
                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN








                                  PENSION SERP









                                October 1, 1999










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                                 TIDEWATER INC.

                          SECOND AMENDED AND RESTATED
                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

                               TABLE OF CONTENTS




PREAMBLE ................................................................  1

ARTICLE 1:  PURPOSE OF THE PLAN .........................................  1

ARTICLE 2:  THE PENSION PLAN ............................................  1

ARTICLE 3:  ADMINISTRATION ..............................................  2

ARTICLE 4:  ELIGIBILITY .................................................  2

ARTICLE 5:  AMOUNT OF SUPPLEMENTAL PENSION BENEFIT ......................  2

ARTICLE 6:  PAYMENT OF SUPPLEMENTAL PENSION BENEFIT .....................  3

ARTICLE 6A: PAYMENT ELECTION IN ANTICIPATION OF A CHANGE OF CONTROL .....  4

ARTICLE 7:  EMPLOYEES' RIGHTS ...........................................  4

ARTICLE 8:  AMENDMENT AND DISCONTINUANCE ................................  5

ARTICLE 8A: CHANGE OF CONTROL ...........................................  5

ARTICLE 9:  RESTRICTIONS ON ASSIGNMENT ..................................  8

ARTICLE 10: NATURE OF AGREEMENT .........................................  8

ARTICLE 11: CONTINUED EMPLOYMENT ........................................  9

ARTICLE 12: BINDING ON EMPLOYER, EMPLOYEES AND THEIR SUCCESSORS .........  9

ARTICLE 13: LAWS GOVERNING ..............................................  9

ARTICLE 14:  MISCELLANEOUS ..............................................  9
     14.1      Claims and Appeal Procedures .............................  9
     14.2      Recovery of Payments Made by Mistake .....................  9

<PAGE>

                                TIDEWATER INC.

                          SECOND AMENDED AND RESTATED
                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN


                                    PREAMBLE

     Tidewater Inc. ("Employer") is the sponsor of the Tidewater Pension Plan
("Pension Plan"), which is a plan qualified under Section 401(a) of the Internal
Revenue Code of 1986 ("Code").  Benefits under the Pension Plan are limited by
various sections of the Code, such as Sections 401(a)(17) and 415.  In order to
provide benefits  to a select group of management or highly compensated
employees equal to the benefits that such employees are prevented from receiving
under the Pension Plan because of those Code limitations, the Employer adopted a
nonqualified unfunded plan known as the Tidewater Inc. Supplemental Executive
Retirement Plan ("Plan"), effective as of July 1, 1991.  The Plan also replaces
certain service lost under the Pension Plan due to breaks in service, and
enhances the benefit calculation formula.  The Employer amended and restated the
Plan effective January 1, 1993, further amended the Plan effective January 1,
1994, adopted two amendments effective October 1, 1999, and hereby amends and
restates the Plan effective October 1, 1999, as set forth below.

                        ARTICLE 1:  PURPOSE OF THE PLAN

     The Employer intends and desires by the adoption of this Plan to recognize
the value to the Employer of past and present services of certain Eligible
Employees and to encourage and assure their continued service with the Employer
by making more adequate provision for their future retirement security.  The
establishment of this Plan is made necessary by certain limitations on
contributions and benefits which are imposed on the Pension Plan by the Code.
The Employer also wishes to compensate certain members of management or highly
compensated employees who may have been disadvantaged by the break in service
rules under the Pension Plan and to enhance the benefit calculation formula.

                          ARTICLE 2:  THE PENSION PLAN

     The Pension Plan, whenever referred to in this Plan, shall mean the
Tidewater Pension Plan, as amended, as it exists as of the date any
determination is made of benefits payable under this Plan.  All terms used in
this Plan shall have the meanings assigned to them under the provisions of the
Pension Plan, unless otherwise qualified by the context.  Since this Plan is
intended to supplement the Pension Plan, any ambiguities or gaps in this Plan
shall be resolved by reference to the Pension Plan document.
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                           ARTICLE 3:  ADMINISTRATION

     This Plan shall be administered by the Compensation Committee of Employer's
Board of Directors, the Employee Benefits Committee, and the Board of Directors
of the Employer, which shall administer this Plan in a manner consistent with
their duties of administration of the Pension Plan.  Each of these governing
bodies shall have full power and authority to interpret, construe and administer
this Plan in accordance with their respective duties under the Pension Plan, and
a governing body's interpretations and constructions hereof and actions
hereunder, including the timing, form, amount or recipient of any payment to be
made hereunder, within the scope of its authority, shall be binding and
conclusive on all persons for all purposes.  No member of a governing body shall
be liable to any person for any action taken or omitted in connection with the
interpretation and administration of this Plan, unless attributable to his own
willful misconduct or lack of good faith.  Each administrator shall be fully
indemnified as provided in the Pension Plan. A member of a governing body shall
not participate in any action or determination regarding his own benefits
hereunder.

                            ARTICLE 4:  ELIGIBILITY

     To be eligible to participate in this Plan, an Employee must satisfy the
following conditions, (a) and (b):

          (a) The Employee must be a Participant in the Pension Plan;

          (b) The Employee must serve as the Chief Executive Officer, the
President, a Vice President or the Corporate Controller of the Employer.

     An Employee who satisfies conditions (a) and (b) is referred to as an
"Eligible Employee."  An Eligible Employee who ceases to be an Eligible Employee
because of a change in his status as an officer under (b), shall have benefits
under this Plan frozen as of the date he ceases to be an officer described in
(b), and his benefits shall be paid as provided in Article 6 and 6A.

     Notwithstanding anything to the contrary, the Plan may not be amended to
preclude the participation in the Plan, on the same basis as other Eligible
Employees, of the person serving on October 1, 1999 as the Chief Executive
Officer, the President, a Vice President or the Corporate Controller of the
Employer, as long as such person continues to serve in such position or in any
equivalent or higher position.

               ARTICLE 5:  AMOUNT OF SUPPLEMENTAL PENSION BENEFIT

     The amount of supplemental pension benefit shall be:

          (a) The supplemental pension benefit payable to an Eligible Employee
or his Beneficiary or Beneficiaries under this Plan shall be the actuarial
equivalent


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(based on the definition of this term in Section 1.02 of the Pension Plan) of
the excess, if any, of (i) over (ii) as described below:

               (i) the benefit which would have been payable to such Eligible
Employee or on his behalf to his Beneficiary or Spouse, as the case may be,
under the Pension Plan (but not taking into account any Additional Monthly
Benefit payable under Section 5.07 of the Pension Plan), if the provisions of
Pension Plan were administered without regard to either the maximum amount of
retirement income limitations of Section 415 of the Code, or the maximum
compensation limitation of Section 401(a)(17) of the Code,

               (ii) the benefit (including any Additional Monthly Benefit) which
is in fact payable to such Eligible Employee or on his behalf to his Beneficiary
or Spouse under the Pension Plan.

          (b) The computation in paragraph (a) above shall be made as though the
factor, 0.85%, in Section 5.01(b)(1) of the Pension Plan were 1.35%.

          (c) The computation in paragraph (i) above shall be made as though the
Employee's service under the Pension Plan included the service prior to a break
in service lost under such Plan as a result of a break in service.  After an
Employee becomes an Eligible Employee, he may request the Employer to provide
him with a written statement of the number of years of service lost under the
Pension Plan.  If the Eligible Employee disagrees with the Employer's
determination, he immediately shall contest it through the Plan's Appeal
Procedure referenced in Article 14, below.  In the absence of the Eligible
Employee's timely request and objection, the Employer's determination shall
become fixed.

          (d) Supplemental pension benefits payable under this Plan to any
recipient shall be computed in accordance with the foregoing, with the objective
that such recipient should receive under this Plan and the Pension Plan the
total amount which would have been payable to that recipient solely under the
Pension Plan (as enriched by (b) and (c)), had neither Section 415 nor Section
401(a)(17) of the Code been applicable thereto.  An Eligible Employee who is not
entitled to benefits under the Pension Plan is not entitled to supplemental
pension benefits under this Plan.

              ARTICLE 6:  PAYMENT OF SUPPLEMENTAL PENSION BENEFIT

     Except as provided in Article 8 or 8A or unless the Employee elects
otherwise under this Article 6 or Article 6A, the supplemental pension benefit
under the Plan with respect to an Employee shall commence at the same time and
be paid in the same form and to the same recipient as the benefit with respect
to the Employee that is payable under the Pension Plan.  An Employee can elect,
on a form provided by the Committee,  to receive a benefit commencing at an
earlier date following termination of employment and after reaching age 55, but
only if the election is made at least 13 months prior to the benefit
commencement date.  The earlier benefit can be paid in any


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form permitted under the Pension Plan. The benefit paid earlier than the benefit
under the Pension Plan shall be determined as if the Pension Plan benefit were
being paid at the same time and in the same form as the benefit under the Plan.

     The foregoing notwithstanding, if the total value of the benefit payable
under the Plan to the Employee or the Employee's Spouse upon the Employee's
termination of employment (by retirement, death or otherwise) is less than
$10,000, the recipient shall receive an immediate lump sum benefit.

                 ARTICLE 6A:  PAYMENT ELECTION IN ANTICIPATION
                              OF A CHANGE OF CONTROL

     An Employee or a former Employee who has not yet satisfied the requirements
to begin to receive payment of benefits under the Plan can also elect at any
time prior to a Change of Control, in a form and manner reasonably satisfactory
to the Company, to have the supplemental pension benefit that becomes payable
under the Plan to such Employee or former Employee following a Change of Control
paid in cash in the form of a lump sum as of the date payments to the Employee
would otherwise commence under the terms of the Plan, without regard to the form
of payment provisions otherwise provided in the Plan and any payment or
distribution elections applicable to the payment of the Employee's or former
Employee's benefit in the absence of a Change of Control.  A former Employee who
has satisfied the requirements to begin to receive the payment of benefits under
the Plan, whether or not payments have commenced, can also elect at any time
prior to a Change of Control, in a form and manner reasonably satisfactory to
the Company, to have the full value of  the remaining supplemental pension
benefits payable to such former Employee paid in a lump sum in cash within five
business days of the Change of Control, without regard to the form of payment
provisions otherwise provided in the Plan and any payment or distribution
elections applicable to the payment of the former Employee's benefit in the
absence of a Change of Control.  The determination of the lump sum amount shall
be made using the same assumptions as are used in the Pension Plan to determine
the amount of a lump sum benefit.

                         ARTICLE 7:  EMPLOYEES' RIGHTS

     No Employee, Spouse or Beneficiary shall have greater rights under this
Plan than those of general creditors of the Employer.  Benefits payable under
this Plan shall be a mere promise to pay in the future and shall be general,
unsecured obligations of the Employer, to be paid by the Employer from its own
funds.  Such payments shall not (i) impose any additional obligation upon the
Employer under the Pension Plan; (ii) be paid from the Pension Plan; or (iii)
have any effect whatsoever upon the Pension Plan.  No Employee or his
Beneficiary or Spouse shall have any title to or beneficial ownership in any
assets which the Employer may use to pay benefits hereunder.  Notwithstanding
the foregoing provisions of this Article 7 and any other provision of the Plan
(including, without limitation, Article 10), the Employer may, in its
discretion, establish a trust to pay amounts becoming payable pursuant to the
Plan, which trust shall be subject to the


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claims of the general creditors of the Employer in the event of its bankruptcy
or insolvency. Notwithstanding any establishment of such a trust, the Company
shall remain responsible for the payment of any amounts so payable which are not
so paid by such trust.

                    ARTICLE 8:  AMENDMENT AND DISCONTINUANCE

     The Employer expects to continue this Plan indefinitely but, except as
otherwise provided, reserves the right to amend or discontinue it if, in its
sole judgment, such a change is deemed necessary or desirable.  However, if the
Employer should amend or discontinue this Plan, the Employer shall continue to
be liable to pay all benefits accrued under this Plan (determined on the basis
of each Employee's presumed termination of employment as of the date of such
amendment or discontinuance), as of the date of such action.  Such accrued
benefits shall be calculated pursuant to the provisions of the Plan immediately
prior to any such amendment or discontinuance.  Upon a discontinuance, all
benefits shall be 100% vested, and a lump sum equal to the actuarial present
value of each Employee's unpaid accrued benefit under this Plan shall be
distributed to the Employee (or his Beneficiary or Spouse), and the Employer
shall have no further obligation under this Plan.  Such lump sum distributions
shall be distributed within the thirty (30) days immediately following such
discontinuance.  No amendment shall be deemed to cause a reduction in an
Employee's accrued benefit under the Plan if the reduction of the benefit under
this Plan is paired with a corresponding increase in the accrued benefit under
the Pension Plan.

                         ARTICLE 8A:  CHANGE OF CONTROL

     8A.01  Effect of Change of Control.  Upon a Change of Control (as defined
in Section 8A.02 hereof) all benefits which have accrued under the Plan shall
immediately become fully vested.  Upon or after a Change of Control, the Plan
shall be deemed to have been discontinued (within the meaning of Article 8
hereof) upon the first to occur of the following:  (i) the date of the Change of
Control if the successor to the Employer shall have failed to assume the
obligations under the Plan prior to or upon such Change of Control, either by
express agreement or by operation of law, (ii) the date of any amendment to the
Plan which reduces or adversely affects either the benefit accrued with respect
to any Employee or the future benefit accrual of any Employee (unless paired
with a corresponding increase in the benefit paid under the Pension Plan), or
(iii) if the Employer shall have established a trust as described in the last
two sentences of Article 7 hereof, any failure of the Employer (or the successor
to the Employer) to make in a timely fashion any contribution to the trust with
respect to benefits accrued under the Plan which may be required by the terms of
such trust.

     8A.02  Definition of Change of Control.  As used in this Section 8A,
'Change of Control' shall mean:

          (i) the acquisition by any 'Person' (as defined in Section 8A.03
     hereof) of 'Beneficial Ownership' (as defined in Section 8A.03 hereof) of
     30% or more of


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     the outstanding Shares of the Company's Common Stock, $0.10 par value per
     share (the 'Common Stock') or 30% or more of the combined voting power of
     the Company's then outstanding securities; provided, however, that for
     purposes of this subsection 8A.02(i), the following shall not constitute a
     Change of Control:

               (A) any acquisition (other than a 'Business Combination' (as
          defined in Section 8A.02(iii) hereof) which constitutes a Change of
          Control under Section 8A.02(iii) hereof) of Common Stock directly from
          the Company,

               (B) any acquisition of Common Stock by the Company or its
          subsidiaries,

               (C) any acquisition of Common Stock by any employee benefit plan
          (or related trust) sponsored or maintained by the Company or any
          corporation controlled by the Company, or

               (D) any acquisition of Common Stock by any corporation pursuant
          to a Business Combination which does not constitute a Change of
          Control under Section 8A.02(iii) hereof; or

          (ii) individuals who, as of the effective date of the Amendment,
     constitute the Board (the 'Incumbent Board') cease for any reason to
     constitute at least a majority of the Board; provided, however, that any
     individual becoming a director subsequent to the effective date of the
     Amendment whose election, or nomination for election by the Company's
     shareholders, was approved by a vote of at least a majority of the
     directors then comprising the Incumbent Board shall be considered a member
     of the Incumbent Board, unless such individual's initial assumption of
     office occurs as a result of an actual or threatened election contest with
     respect to the election or removal of directors or other actual or
     threatened solicitation of proxies or consents by or on behalf of a Person
     other than the Incumbent Board; or

          (iii)  consummation of a reorganization, merger or consolidation
     (including a merger or consolidation of the Company or any direct or
     indirect subsidiary of the Company), or sale or other disposition of all or
     substantially all of the assets of the Company (a 'Business Combination'),
     in each case, unless, immediately following such Business Combination,

               (A) the individuals and entities who were the Beneficial Owners
          of the Company's outstanding Common Stock and the Company's voting
          securities entitled to vote generally in the election of directors
          immediately prior to such Business Combination have direct or indirect
          Beneficial Ownership, respectively, of more than 50% of the then
          outstanding shares of common stock, and more than 50% of the combined
          voting power of the then outstanding voting securities entitled to
          vote generally in the


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          election of directors, of the Post-Transaction Corporation (as defined
          in Section 8A.03 hereof), and

               (B) except to the extent that such ownership existed prior to the
          Business Combination, no Person (excluding the Post-Transaction
          Corporation and any employee benefit plan or related trust of either
          the Company, the Post-Transaction Corporation or any subsidiary of
          either corporation) Beneficially Owns, directly or indirectly, 30% or
          more of the then outstanding shares of common stock of the corporation
          resulting from such Business Combination or 30% or more of the
          combined voting power of the then outstanding voting securities of
          such corporation, and

               (C) at least a majority of the members of the board of directors
          of the Post-Transaction Corporation were members of the Incumbent
          Board at the time of the execution of the initial agreement, or of the
          action of the Board, providing for such Business Combination; or

          (iv) approval by the shareholders of the Company of a complete
     liquidation or dissolution of the Company.

     8A.03  Other Definitions.  As used in Section 8A.02 hereof, the following
words or terms shall have the meanings indicated:

          (i) Affiliate:  'Affiliate' (and variants thereof) shall mean a Person
     that controls, or is controlled by, or is under common control with,
     another specified Person, either directly or indirectly.

          (ii) Beneficial Owner:  'Beneficial Owner' (and variants thereof),
     with respect to a security, shall mean a Person who, directly or indirectly
     (through any contract, understanding, relationship or otherwise), has or
     shares (i) the power to vote, or direct the voting of, the security, and/or
     (ii) the power to dispose of, or to direct the disposition of, the
     security.

          (iii)  Person:  'Person' shall mean a natural person or company, and
     shall also mean the group or syndicate created when two or more Persons act
     as a syndicate or other group (including, without limitation, a partnership
     or limited partnership) for the purpose of acquiring, holding, or disposing
     of a security, except that 'Person' shall not include an underwriter
     temporarily holding a security pursuant to an offering of the security.

          (iv) Post-Transaction Corporation:  Unless a Change of Control
     includes a Business Combination (as defined in Section 8A.02(iii) hereof),
     'Post-Transaction Corporation' shall mean the Company after the Change of
     Control.  If a Change of Control includes a Business Combination, 'Post-
     Transaction Corporation' shall mean the corporation resulting from the
     Business Combination unless, as a result of such Business Combination, an
     ultimate parent corporation



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     controls the Company or all or substantially all of the Company's assets
     either directly or indirectly, in which case, 'Post-Transaction
     Corporation' shall mean such ultimate parent corporation.

                     ARTICLE 9:  RESTRICTIONS ON ASSIGNMENT

     The interest of an Employee or his Beneficiary or Spouse may not be sold,
transferred, assigned, or encumbered in any manner, either voluntarily or
involuntarily, and any attempt so to anticipate, alienate, sell, transfer,
assign, pledge, encumber, or charge the same shall be null and void; neither
shall the benefits hereunder be liable for or subject to the debts, contracts,
liabilities, engagement, or torts of any person to whom such benefits or funds
are payable, nor shall they be subject to garnishment attachment, or other legal
or equitable process nor shall they be an asset in bankruptcy, except that no
amount shall be payable hereunder until and unless any and all amounts
representing debts or other obligations owed to the Employer or any affiliate of
the Employer by the Employee with respect to whom such amount would otherwise be
payable shall have been fully paid and satisfied.  The interest of any Employee,
Beneficiary or Spouse shall be held subject to the maximum restraint on
alienation permitted or required by applicable Louisiana law.

                        ARTICLE 10:  NATURE OF AGREEMENT

     Eligible Employees and their Beneficiaries by virtue of participating under
this Plan have only an unsecured right to receive benefits from their Employer
as a general creditor of the Employer.  The Plan constitutes a mere promise to
make payments in the future. The adoption of the Plan and any setting aside of
amounts by the Employer with which to discharge its obligations hereunder shall
not be deemed to create a trust for the benefit of Eligible Employees or their
Beneficiaries; except as provided in any trust document, legal and equitable
title to any funds so set aside shall remain in the Employer, and any recipient
of benefits hereunder shall have no security or other interest in such funds.
Any and all funds so set aside shall remain subject to the claims of the general
creditors of the Employer, present and future, and no payment shall be made
under this Plan unless the Employer is then solvent.  This provision shall not
require the Employer to set aside any funds, but the Employer may set aside such
funds if it chooses to do so.

                       ARTICLE 11:  CONTINUED EMPLOYMENT

     Nothing contained herein shall be construed as conferring upon any Employee
the right to continue in the employ of the Employer in any capacity.



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                  ARTICLE 12:  BINDING ON EMPLOYER, EMPLOYEES
                               AND THEIR SUCCESSORS












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     This Plan shall be binding upon and inure to the benefit of the Employer,
its successors and assigns and each Eligible Employee and his heirs, executors,
administrators and legal representatives.

                          ARTICLE 13:  LAWS GOVERNING

     This Plan shall be construed in accordance with and governed by the laws of
the State of Louisiana, except to the extent that the Plan is governed by the
Employee Retirement Income Security Act of 1974 ("ERISA").  It is the Employer's
intent that the Plan shall be exempt from ERISA's provisions, to the maximum
extent permitted by law.  To the extent that the Plan is an excess benefit plan
(as defined in Section 3(36) of ERISA), it shall be exempt from coverage
entirely, as provided in ERISA Section 4(b)(5).  The Plan is intended to be
unfunded for federal income tax purposes and for purposes of title I of ERISA
and intended to provide deferred compensation only for a select group of
management or highly compensated employees and shall be exempt from Parts 2, 3,
and 4 of ERISA, pursuant to Sections 201(2), 301(a)(3), and 401(a)(1) of ERISA.

                           ARTICLE 14:  MISCELLANEOUS

      14.1 Claims and Appeal Procedures.  All disputes over benefits allegedly
due under this Plan shall be resolved through the procedures for making claims,
and appealing from denials of claims, that are set forth in the Summary Plan
Description of the Pension Plan.

      14.2 Recovery of Payments Made by Mistake. Notwithstanding anything to the
contrary, an Eligible Employee or other person receiving amounts from the Plan
is entitled only to those benefits provided by the Plan and promptly shall
return any payment, or portion thereof, made by mistake of fact or law. The
Committee may offset the future benefits of any recipient who refuses to return
an erroneous payment, in addition to pursuing any other remedies provided by
law.


     EXECUTED effective this 1st day of October, 1999.


                              TIDEWATER INC.


                              By: /s/ Ken C. Tamblyn
                                  ----------------------------------
                                  Ken C. Tamblyn
                                  Executive Vice President and Chief
                                  Financial Officer


ATTEST:



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By: /s/ Michael L. Goldblatt
    ---------------------------
     Michael L. Goldblatt
     Assistant Secretary


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