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                                EXHIBIT 10.13B



                               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
("Bank") has agreed to extend the maturity date of that certain credit
accommodation granted by Bank to Suburban Water Systems ("Borrower") in the
maximum principal amount of Four Million Dollars ($4,000,000.00) pursuant to the
terms and conditions of that certain credit Agreement between Bank and Borrower
dated as of June 30, 1996, 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 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.
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     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/Daniel N. Evans
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       DANIEL N. EVANS
Title: Vice President Finance
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By:    /s/Peter J. Moerbeek
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       PETER J. MOERBEEK
Title: Secretary
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