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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                             ---------------------

                                  FORM 10-Q/A
                               (AMENDMENT NO. 1)

(MARK ONE)

    [X]        QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

                 FOR THE QUARTERLY PERIOD ENDED MARCH 31, 2003

                                       OR

    [ ]        TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

             FOR THE TRANSITION PERIOD FROM           TO

                         COMMISSION FILE NUMBER 1-7320

                             ---------------------

                              ANR PIPELINE COMPANY
             (Exact Name of Registrant as Specified in its Charter)

<Table>
<S>                                                <C>
                  DELAWARE                                          38-1281775
        (State or Other Jurisdiction                             (I.R.S. Employer
     of Incorporation or Organization)                         Identification No.)

              EL PASO BUILDING
           1001 LOUISIANA STREET                                      77002
               HOUSTON, TEXAS                                       (Zip Code)
  (Address of Principal Executive Offices)
</Table>

                        Telephone Number: (713) 420-2600

                             ---------------------

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.  Yes [X]  No [ ]

     Indicate by check mark whether the registrant is an accelerated filer (as
defined in Rule 12b-2 of the Exchange Act).  Yes [ ]  No [X]

     Indicate the number of shares outstanding of each of the issuer's classes
of common stock, as of the latest practicable date.

     Common Stock, par value $1 per share. Shares outstanding on June 20, 2003:
1,000

     ANR PIPELINE COMPANY MEETS THE CONDITIONS OF GENERAL INSTRUCTION H(1)(a)
AND (b) OF FORM 10-Q AND IS THEREFORE FILING THIS REPORT WITH A REDUCED
DISCLOSURE FORMAT AS PERMITTED BY SUCH INSTRUCTION.

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                                EXPLANATORY NOTE

     This Amendment on Form 10-Q/A constitutes Amendment No. 1 to our Quarterly
Report on Form 10-Q for the period ended March 31, 2003, which was previously
filed with the Securities and Exchange Commission (SEC) on May 14, 2003 (the
Quarterly Report). We are amending the disclosure set forth in Item 14 of the
Quarterly Report in its entirety.

     This Amendment only amends Item 14 of the Quarterly Report as specified
above. It does not affect the original financial statements and footnotes filed
in the Quarterly Report and does not reflect events occurring after the original
filing date of May 14, 2003.

ITEM 14.  CONTROLS AND PROCEDURES

     Evaluation of Controls and Procedures.  Under the supervision and with the
participation of management, including our principal executive officer and
principal financial officer, we have evaluated the effectiveness of the design
and operation of our disclosure controls and procedures (Disclosure Controls)
and internal controls (Internal Controls) within 90 days of the filing date of
this Quarterly Report pursuant to Rules 13a-15 and 15d-15 under the Securities
Exchange Act of 1934 (Exchange Act).

     Definition of Disclosure Controls and Internal Controls.  Disclosure
Controls are our controls and other procedures that are designed to ensure that
information required to be disclosed by us in the reports that we file or submit
under the Exchange Act is recorded, processed, summarized and reported, within
the time periods specified under the Exchange Act. Disclosure Controls include,
without limitation, controls and procedures designed to ensure that information
required to be disclosed by us in the reports that we file under the Exchange
Act is accumulated and communicated to our management, including our principal
executive officer and principal financial officer, as appropriate to allow
timely decisions regarding required disclosure. Internal Controls are procedures
which are designed with the objective of providing reasonable assurance that (1)
our transactions are properly authorized; (2) our assets are safeguarded against
unauthorized or improper use; and (3) our transactions are properly recorded and
reported, all to permit the preparation of our financial statements in
conformity with generally accepted accounting principles.

     Limitations on the Effectiveness of Controls.  ANR Pipeline Company's
management, including the principal executive officer and principal financial
officer, does not expect that our Disclosure Controls and Internal Controls will
prevent all errors and all fraud. The design of a control system must reflect
the fact that there are resource constraints, and the benefits of controls must
be considered relative to their costs. Because of the inherent limitations in
all control systems, no evaluation of controls can provide absolute assurance
that all control issues and instances of fraud, if any, within the company have
been detected. These inherent limitations include the realities that judgments
in decision-making can be faulty, and that breakdowns can occur because of
simple errors or mistakes. Additionally, controls can be circumvented by the
individual acts of some persons, by collusion of two or more people, or by
management override of the controls. The design of any system of controls also
is based in part upon certain assumptions about the likelihood of future events.
Therefore, a control system, no matter how well conceived and operated, can
provide only reasonable, not absolute, assurance that the objectives of the
control system are met. Our Disclosure Controls and Internal Controls are
designed to provide such reasonable assurances of achieving our desired control
objectives, and our principal executive officer and principal financial officer
have concluded that our Disclosure Controls and Internal Controls are effective
in achieving that level of reasonable assurance.

     No Significant Changes in Internal Controls.  We have sought to determine
whether there were any "significant deficiencies" or "material weaknesses" in
ANR Pipeline Company's Internal Controls, or whether the company had identified
any acts of fraud involving personnel who have a significant role in ANR
Pipeline Company's Internal Controls. This information was important both for
the controls evaluation generally and because the principal executive officer
and principal financial officer are required to disclose that information to our
Board's Audit Committee and our independent auditors and to report on related
matters in this section of the Quarterly Report. The principal executive officer
and principal financial officer note that, from the date of the controls
evaluation to the date of this Quarterly Report, there have been no significant
changes in

                                        1
<PAGE>

Internal Controls or in other factors that could significantly affect Internal
Controls, including any corrective actions with regard to significant
deficiencies and material weaknesses.

     Effectiveness of Disclosure Controls.  Based on the controls evaluation,
our principal executive officer and principal financial officer have concluded
that the Disclosure Controls are effective to ensure that material information
relating to ANR Pipeline Company and its consolidated subsidiaries is made known
to management, including the principal executive officer and principal financial
officer, on a timely basis.

     Officer Certifications.  The certifications from the principal executive
officer and principal financial officer required under Sections 302 and 906 of
the Sarbanes-Oxley Act of 2002 have been included herein, or as Exhibits to this
Quarterly Report, as appropriate.

                                        2
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                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                              ANR PIPELINE COMPANY

Date: June 20, 2003                             /s/ JOHN W. SOMERHALDER II
                                              ----------------------------------
                                                    John W. Somerhalder II
                                              Chairman of the Board and Director
                                                (Principal Executive Officer)

Date: June 20, 2003                                 /s/ GREG G. GRUBER
                                              ----------------------------------
                                                        Greg G. Gruber
                                                    Senior Vice President,
                                                   Chief Financial Officer,
                                                    Treasurer and Director
                                                   (Principal Financial and
                                                      Accounting Officer)

                                        3
<PAGE>

                                 CERTIFICATION

I, John W. Somerhalder II, certify that:

     1. I have reviewed this quarterly report on Form 10-Q/A of ANR Pipeline
Company;

     2. Based on my knowledge, this quarterly report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this quarterly
report;

     3. The registrant's other certifying officers and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-14 and 15d-14) for the registrant and have:

          (a) designed such disclosure controls and procedures to ensure that
     material information relating to the registrant, including its consolidated
     subsidiaries, is made known to us by others within those entities,
     particularly during the period in which this quarterly report is being
     prepared;

          (b) evaluated the effectiveness of the registrant's disclosure
     controls and procedures as of a date within 90 days prior to the filing
     date of this quarterly report (the "Evaluation Date"); and

          (c) presented in this quarterly report our conclusions about the
     effectiveness of the disclosure controls and procedures based on our
     evaluation as of the Evaluation Date;

     4. The registrant's other certifying officers and I have disclosed, based
on our most recent evaluation, to the registrant's auditors and the audit
committee of registrant's board of directors (or persons performing the
equivalent function):

          (a) all significant deficiencies in the design or operation of
     internal controls which could adversely affect the registrant's ability to
     record, process, summarize and report financial data and have identified
     for the registrant's auditors any material weaknesses in internal controls;
     and

          (b) any fraud, whether or not material, that involves management or
     other employees who have a significant role in the registrant's internal
     controls; and

     5. The registrant's other certifying officers and I have indicated in this
quarterly report whether there were significant changes in internal controls or
in other factors that could significantly affect internal controls subsequent to
the date of our most recent evaluation, including any corrective actions with
regard to significant deficiencies and material weaknesses.

                                              /s/ JOHN W. SOMERHALDER II
                                          --------------------------------------
                                                  John W. Somerhalder II
                                                  Chairman of the Board
                                              (Principal Executive Officer)
                                                   ANR Pipeline Company

Date: June 20, 2003

                                        4
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                                 CERTIFICATION

I, Greg G. Gruber, certify that:

     1. I have reviewed this quarterly report on Form 10-Q/A of ANR Pipeline
Company;

     2. Based on my knowledge, this quarterly report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this quarterly
report;

     3. The registrant's other certifying officers and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-14 and 15d-14) for the registrant and have:

          (a) designed such disclosure controls and procedures to ensure that
     material information relating to the registrant, including its consolidated
     subsidiaries, is made known to us by others within those entities,
     particularly during the period in which this quarterly report is being
     prepared;

          (b) evaluated the effectiveness of the registrant's disclosure
     controls and procedures as of a date within 90 days prior to the filing
     date of this quarterly report (the "Evaluation Date"); and

          (c) presented in this quarterly report our conclusions about the
     effectiveness of the disclosure controls and procedures based on our
     evaluation as of the Evaluation Date;

     4. The registrant's other certifying officers and I have disclosed, based
on our most recent evaluation, to the registrant's auditors and the audit
committee of registrant's board of directors (or persons performing the
equivalent function):

          (a) all significant deficiencies in the design or operation of
     internal controls which could adversely affect the registrant's ability to
     record, process, summarize and report financial data and have identified
     for the registrant's auditors any material weaknesses in internal controls;
     and

          (b) any fraud, whether or not material, that involves management or
     other employees who have a significant role in the registrant's internal
     controls; and

     5. The registrant's other certifying officers and I have indicated in this
quarterly report whether there were significant changes in internal controls or
in other factors that could significantly affect internal controls subsequent to
the date of our most recent evaluation, including any corrective actions with
regard to significant deficiencies and material weaknesses.

                                                  /s/ GREG G. GRUBER
                                          --------------------------------------
                                                      Greg G. Gruber
                                          Senior Vice President, Chief Financial
                                                  Officer and Treasurer
                                              (Principal Financial Officer)
                                                   ANR Pipeline Company

Date: June 20, 2003

                                        5
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                              ANR PIPELINE COMPANY

                                  EXHIBIT LIST

<Table>
<Caption>
  EXHIBIT
   NUMBER                              DESCRIPTION
  -------                              -----------
<C>            <S>
    99.A       Certification of Principal Executive Officer pursuant to 18
               U.S.C. sec. 1350 as adopted pursuant to sec. 906 of the
               Sarbanes-Oxley Act of 2002.
    99.B       Certification of Principal Financial Officer pursuant to 18
               U.S.C. sec. 1350 as adopted pursuant to sec. 906 of the
               Sarbanes-Oxley Act of 2002.
</Table>