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                                                                    Exhibit 31.1


                            CERTIFICATION PURSUANT TO
                                RULE 15D-14(A) OF
                       THE SECURITIES EXCHANGE ACT OF 1934
                             AS ADOPTED PURSUANT TO
                  SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002


I, Harry K. Hornish, Jr., certify that:

1.    I have reviewed this quarterly report on Form 10-Q of National Waterworks,
      Inc.;

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.    Based on my knowledge, the financial statements, and other financial
      information included in this quarterly report, fairly present in all
      material respects the financial condition, results of operations, and cash
      flows of the registrant as of, and for, the periods presented in this
      quarterly report;

4.    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 we
      have:

                  a) designed such disclosure controls and procedures, or caused
            such disclosure controls and procedures to be designed under our
            supervision, to ensure that material information relating to the
            registrant 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 and presented in this report our conclusions
            about the effectiveness of the disclosure controls and procedures,
            as of the end of the period covered by this report based on such
            evaluation; and

                  c) disclosed in this report any change in the registrant's
            internal control over financial reporting that occurred during the
            registrant's most recent fiscal quarter that has materially
            affected, or is reasonably likely to materially affect, the
            registrant's internal control over financial reporting;

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

                  a) all significant deficiencies and material weaknesses in the
            design or operation of internal control over financial reporting
            which are reasonably likely to adversely affect the registrant's
            ability to record, process, summarize and report financial
            information; and

                  b) any fraud, whether or not material, that involves
            management or other employees who have a significant role in the
            registrant's internal control over financial reporting.


Date: October 29, 2003                     /s/ Harry K. Hornish, Jr.
                                           -------------------------------------
                                           Harry K. Hornish, Jr.
                                           President and Chief Executive Officer