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                                                                  Exhibit 10.28

                              TAX SHARING AGREEMENT

            TAX SHARING AGREEMENT, made as of November 22, 2002, by and among
National Waterworks Holdings, Inc., a Delaware corporation having its principal
place of business at American Plaza, 200 West Highway 6, Suite 620, Waco, TX
76712 ("Holding"), and those corporations that have executed this Agreement and
whose names and principal places of business are set forth on Exhibit A hereto
(all of which are direct or indirect domestic subsidiaries of Holding and are
includible in the consolidated Federal income tax return of the affiliated group
(within the meaning of Section 1504 of the Internal Revenue Code of 1986, as
amended (the "Code")) of which Holding is the common parent corporation
(hereinafter, the "Holding Group") for the fiscal year ended December 31, 2002),
and such other parties as may become members of the Holding Group in subsequent
fiscal years for which Holding files a consolidated Federal income tax return as
the common parent corporation of an affiliated group, and who execute this
Agreement (hereinafter, sometimes referred to as the "Subsidiary").

            Holding and the Subsidiary wish to provide for payment of the
consolidated Federal income tax and certain state and local tax liabilities of
the Holding Group by Holding; for the contribution to such payment by the
various members of the Holding Group, including National Waterworks, Inc., a
Delaware corporation having its principal place of business at American Plaza,
200 West Highway 6, Suite 620, Waco, TX 76712 ("Water"), and any direct and
indirect subsidiaries of Water ("Water Subsidiaries") that may be includible in
the Holding Group (hereinafter, Water and such Water Subsidiaries are sometimes
collectively referred to as the "Water Group"), to which such liability may be
attributable in whole or in part; and for the reimbursement by Holding to those
Subsidiaries that produce losses or credits in any fiscal year in the amount of
the benefit that such Subsidiary would be entitled to with respect to such
losses
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or credits on a separate return basis, or for the benefit, in whole or in part,
that such losses or credits produce for the Holding Group.

            In consideration of the foregoing, and of the mutual covenants and
promises herein contained, Holding and the Subsidiaries agree as follows:

      1. Allocation and Payment of Tax Liability of Members of Group.

            (a) For the fiscal year ended December 31, 2002 and for each
subsequent fiscal year for which this Agreement may remain in effect, each
Subsidiary, for so long as it is a member of the Holding Group, shall be
required to pay to Holding (in the manner provided in paragraph 1(c) hereof), as
its share of the consolidated Federal income tax liability of the Holding Group,
an amount equal to the Federal income tax liability that would have been payable
by such Subsidiary for such year if it had filed a separate income tax return
for such year and all prior years; provided, however, that in computing separate
return tax liability, no account shall be taken of any deduction, loss or credit
of any Subsidiary to the extent that such Subsidiary has previously received
payment therefor, pursuant to Section 3 hereof. If a Subsidiary ceases to be a
member of the Holding Group during a taxable year, such Subsidiary shall be
required to pay to Holding only that portion of such Subsidiary's separate
return tax liability that is allocable to the portion of the taxable year in
which Subsidiary was a member of the Holding Group. Payments shall be required
to be made in each fiscal year pursuant to this Section without regard to the
actual consolidated Federal income tax liability, if any, of the Holding Group
for such year.

            (b) For the purposes of this Agreement, if, in any fiscal year, one
or more Water Subsidiaries are includible in the Holding Group, all members of
the Water Group shall be deemed to constitute a single member of the Holding
Group, and any portion of the Holding


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Group consolidated Federal income tax liability for any fiscal year that is
apportioned to the Water Group in accordance with this Section shall be
allocated among the members thereof in such manner as they may agree. The amount
of separate return tax liability required to be paid to Holding by Water or the
Water Group in any year pursuant to this Section shall be determined as if Water
had filed a consolidated Federal income tax return for such year and for all
prior years, on behalf of itself and all Water Subsidiaries that were includible
corporations described in Section 1504(a)(1) of the Code for such year or prior
years, as the case may be.

            (c) Each member (or group of members) of the Holding Group shall
make payment to Holding of any consolidated Federal income tax liability
allocated to it pursuant to this Section 1, and Holding shall have sole
responsibility for making any required payments to the Internal Revenue Service
(the "IRS") in satisfaction of the consolidated Federal income tax liability of
the Holding Group for each fiscal year. Subject to the provisions of Section
1(d) below, for each quarter of each fiscal year after the year ended December
31, 2002, each member (or group of members) of the Holding Group shall make
payment to Holding of any amount required to be paid pursuant to this Section no
later than the date upon which such member (or group of members) would be
required to make an installment payment of estimated income tax to the IRS for
such quarter, in accordance with Section 6655 of the Code. The amount of any
overpayment or underpayment pursuant to this Section shall be credited against
or added to, as the case may be, the amount otherwise required to be paid for
the fiscal quarter within which the amount of such overpayment or underpayment
first becomes reasonably ascertainable; provided, however, that, upon written
request (including supporting schedules) of any member (or group of members),
made after the close of any fiscal year but within the period described in
Section 6425(a)(1) of the Code, Holding shall repay to such member (or group of
members), within the


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period described in Section 6425(b)(1) of the Code, the amount of any net
remaining overpayment of consolidated tax liability made by such member (or
group of members) for such year.

            (d) Anything contained in this Agreement to the contrary
notwithstanding, any payment to be made by any party hereto to any other party
hereto may be deferred until such time as either (I) the party obligated to make
such payment elects to make the relevant payment or (II) the party entitled to
receive such payment demands that such payment be made. All such deferred
payments shall bear interest at an annual rate that approximates the average
interest rate under Water's revolving credit facility over the time period that
such payment is deferred, computed on the basis of the actual number of days
elapsed over a 365-day period.

      2. Payment for Tax Benefits of Members. From and after the date hereof, if
any member (or group of members) of the Holding Group would be entitled to a
refund of Federal income taxes previously paid in any prior fiscal year,
computed on a separate return basis (in the manner described in Section 1
hereof), as a result of any losses, deductions or credits claimed by such member
(or group of members) for any fiscal year for which this Agreement may be in
effect (any such entitlement to a refund being referred to herein as a "Separate
Return Tax Benefit"), whether by reason of a carryback of a net operating loss,
or a net capital loss or tax credit, or otherwise, then, upon written request
(including supporting schedules) of such member (or group of members), made
within the period described in Section 6411(a) of the Code, Holding shall pay
the amount of such Separate Return Tax Benefit to such member, within the period
described in Section 6411(b) of the Code (subject to the provisions of Section
1(d) above). In the case of Water and Water Subsidiaries, the amount of the
Separate Return Tax Benefit for any year shall be computed as if watwr had filed
a consolidated Federal income tax


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return for such year and for all prior years on behalf of itself and all other
Water Subsidiaries that were includible corporations described in Section
1504(a)(1) of the Code. The amount of any payment required to be made to any
member (or group of members) pursuant to this Section 2 shall be reduced by any
amount previously paid to such member (or group of members) with respect to such
losses, deductions or credits pursuant to Section 3 hereof.

      3. Payment for Tax Benefits of Group.

            (a) If, for any fiscal year during which this Agreement is in
effect, any member (or group of members) shall have a negative separate return
tax liability (hereinafter, a "Loss Member"), Holding intends to pay to such
Loss Member an amount equal to the tax benefit realized by the Holding Group for
such year (the "Group Tax Benefit") as a result of such negative separate return
tax liability. For purposes of this Agreement, the Group Tax Benefit for any
fiscal year shall be equal to the excess, if any, of (i) the sum of the separate
return tax liabilities of each member of the Holding Group having a positive
separate return tax liability for such year, over (ii) the actual consolidated
Federal income tax liability of the Holding Group for such year. For purposes of
this Section 3, "separate return tax liability" shall be computed in accordance
with, and subject to the exceptions and limitations provided in Treas. Reg.
Section 1.1552-1(a)(2)(ii). "Negative separate return tax liability" shall
similarly be ascertained under the principles of Treas. Reg. Section
1.1552-1(a)(2)(ii), as if the Loss Member had filed a separate return for such
fiscal year as its first separate return year and allocated to such separate
return year carryover and carryback items of consolidated net operating loss,
consolidated net capital loss, consolidated unused investment credit,
consolidated unused foreign tax credit, and consolidated excess charitable
contributions under the provisions of Treas. Reg. Section 1.1502-79. In the case
of


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the Water Group, separate return tax liability and negative separate return tax
liability shall be computed in accordance with the principles set forth in this
Section 3, on a consolidated basis.

            (b) Within 90 days after the beginning of each fiscal year for which
this Agreement may be in effect, Holding shall give written notice to each
Subsidiary of its intention to pay one or more Loss Members an amount equal to
all, or any portion, of their proportionate part (determined in the manner
provided in paragraph 3(a)) of any Group Tax Benefit that may be realized by the
Holding Group for such year. Holding intends to make such payments on a
quarterly basis, in the manner described in paragraph 1(c) hereof; provided,
however, that all payments made pursuant to this Section 3 shall be made in the
sole discretion of Holding, and Holding shall have no obligations or liability
whatsoever with respect thereto to any Loss Member; and provided, further, that
any payment made to any Loss Member in a fiscal year pursuant to this Section 3
shall be reduced by any amount previously paid to such Loss Member with respect
to such year under Section 2 hereof.

      4. Adjustments. Any adjustment of income, deduction, or credit that
results after the fiscal year in question by reason of any carryback, amended
return, claim for refund, or audit shall be given effect by redetermining
amounts payable and reimbursable for such fiscal year hereunder as if such
adjustment had been part of the original determination hereunder, with interest
payable in the amounts provided in Section 6611 of the Code. Any increases in
the consolidated Federal income tax liability of the Holding Group, and any
penalties and interest imposed with respect to any consolidated Federal income
tax return filed on behalf of the Holding Group, shall be given effect by
redetermining amounts payable for such fiscal year as if such adjustment had
been part of the original determination hereunder.


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      5. Alternative Minimum Tax. Each Subsidiary shall be required to pay to
Holding, as its share of any alternative minimum tax imposed on the Holding
Group pursuant to Section 55 of the Code, an amount of such liability that
Holding shall allocate to each Subsidiary, provided that any such amounts so
allocated pursuant to this Section 5 shall be allocated by Holding in a manner
that is equitable and is consistent with Section 55 and Section 1502 of the
Code, and the Treasury Regulations promulgated thereunder, including any
amendments thereto and consistent with the allocations of tax liability pursuant
to Section 1 hereof.

      6. State Taxes. If, at any time from and after the date hereof, the
liability of Holding and the Subsidiaries for any state or local income or
franchise taxes is determined on a consolidated or combined basis, this
Agreement shall be applied in like manner to determine liability for, and tax
benefit payments with respect to, such taxes.

      7. Termination. This Agreement may be terminated at any time upon mutual
agreement of the parties hereto; provided, however, that such termination shall
not relieve Holding of the obligation to make payments to any Subsidiary
pursuant to Section 2 hereof for any separate return tax benefit to which such
Subsidiary would have been entitled (if this Agreement had remained in effect)
as a result of any loss, deductions or credits taken by such Subsidiary for any
fiscal year for which this Agreement was in effect, nor will it relieve Holding
or the Subsidiaries of any obligations pursuant to Section 4 hereof.

      8. Effective Date. This Agreement shall be effective for the taxable year
of the Holding Group ended December 31, 2002, and for all taxable years
thereafter.

      9. Captions. All section captions contained in this Agreement are for
convenience only and shall not be deemed a part of this Agreement.


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      10. Counterparts. This Agreement may be executed in counterparts, each of
which shall constitute an original and all of which, when taken together, shall
constitute one agreement.

      11. Governing Law. This Agreement shall be governed by the laws applicable
to contracts entered into and to be fully performed within the State of New York
by residents thereof.

      12. Successors and Assigns. This Agreement shall be binding upon and shall
inure to the benefit of the parties hereto and their respective successors and
assigns.


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      IN WITNESS WHEREOF, Holding and the Subsidiaries have executed this
Agreement as of the day and year first above written.

                                              NATIONAL WATERWORKS HOLDINGS, INC.


                                              By: /s/ Harry K. Hornish
                                                 ---------------------
                                                 Name:  Harry K. Hornish
                                                 Title: President and C.E.O.


                                              NATIONAL WATERWORKS, INC.

                                              By: /s/ Mechelle Slaughter
                                                 -----------------------
                                                 Name:  Mechelle Slaughter
                                                 Title: C.F.O. and Secretary


                                      S-1
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                                    EXHIBIT A

<TABLE>
<CAPTION>
Name                                          Principal Place of Business
<S>                                           <C>
National Waterworks, Inc.                     American Plaza
                                              200 West Highway 6
                                              Suite 620
                                              Waco, TX  76712
</TABLE>