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                                 EXHIBIT 10.4F



                               September 1, 1997


Southwest Water Company
225 N. Barranca Ave., Suite 200
West Covina, CA 91719

Gentlemen:

     This letter is to confirm that Wells Fargo Bank, National Association,
successor-by-merger to First Interstate Bank of California ("Bank") has agreed
to extend the maturity date of that certain credit accommodation granted by Bank
to Southwest Water Company ("Borrower") in the original maximum principal amount
of Five Million dollars ($5,000,000.00) with said principal amount subsequently
increased to Six Million Dollars ($6,000,000.00) pursuant to the terms and
conditions of that certain Credit Agreement between Bank and Borrower dated as
of December 22, 1992, as amended from time to time (the "Agreement").

     The maturity date of said credit accommodation is hereby extended until
November 1, 1997.  Until such date, all terms and conditions of the Agreement
which pertain to said credit accommodation shall remain in full force and
effect, except as expressly modified hereby.  The promissory note dated as of
December 22, 1992, as modified and/or amended from time to time, executed by
Borrower and payable to the order of Bank which evidences said credit
accommodation, a copy of which is attached hereto as Exhibit A (the "Note"),
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shall be deemed modified as of the date this letter is acknowledged by Borrower
to reflect the new maturity date set forth above.  All other terms and
conditions of the note remain in full force and effect, without waiver or
modification.

     Borrower acknowledges that Bank has not committed to make any renewal of
further extension of the maturity date of the above-described credit
accommodation beyond the new maturity date specified herein, and that any such
renewal of further extension
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remains in the sole discretion of Bank.  This letter constitutes the entire
agreement between Bank and Borrower with respect to the maturity date extension
for the above-described credit accommodation, and supersedes all prior
negotiations, discussions and correspondence concerning said extension.

          Please acknowledge your acceptance of the terms and conditions
contained herein by dating and signing one copy below and returning it to my
attention at the above address on or before September 15, 1997.

                              Very truly yours,

                              WELLS FARGO BANK,
                              NATIONAL ASSOCIATION SUCCESSOR-
                              BY-MERGER TO FIRST INTERSTATE
                              BANK OF CALIFORNIA

                              By: /s/ Richard Madsen
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                                    RICHARD MADSEN
                                    Vice President

Acknowledged and accepted as of September 1, 1997



SOUTHWEST WATER COMPANY

By:      /s/Peter J. Moerbeek
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          PETER J. MOERBEEK
Title:    Vice President Finance, CFO
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By:       /s/Stephen J. Muzi
          ------------------
          STEPHEN J. MUZI
Title:    Corporate Controller
          --------------------