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Exhibit 10.15

AMENDMENT NO. 1
TO AMENDED AND RESTATED CREDIT AGREEMENT

        This Amendment No. 1 (the "Amendment") dated as of October 14, 2004 is
between Bank of America, N.A. (the "Bank") and Southwest Water Company, a
Delaware corporation (the "Borrower").

RECITALS

        A.    The Bank and the Borrower entered into a certain Amended and
Restated Credit Agreement dated as of July 7, 2004 (the "Agreement").

        B.    The Bank and the Borrower desire to amend the Agreement.

AGREEMENT

        1.    Definitions.    Capitalized terms used but not defined in this
Amendment shall have the meaning given to them in the Agreement.

        2.    Amendments.    The Agreement is hereby amended as follows:

        2.1    A defined term is added to Section 1.01, to provide as follows:

"'Additional Revolving Commitment Maturity Date'.    The earlier to occur of
September 30, 2006 or the date of the closing of NMUI's (as defined hereinafter)
placement of $12,000,000 of first mortgage bonds, currently anticipated to
transpire by October 31, 2004."

        2.2    The defined term "Maturity Date," set forth in Section 1.01 is
eliminated in its entirety, and is replaced with the following defined term, to
be added to Section 1.01:

"'Revolving Commitment Maturity Date': September 30, 2006."

        2.3    The defined term, "Maturity Date," is eliminated from
Section 2.01(a), and is replaced, in both instances in which it appears, with
the defined term, "Revolving Commitment Maturity Date."

        All other language in Section 2.01(a) remains unchanged.

        2.4    The defined term, "Maturity Date," is eliminated from
Section 2.01(e), and is replaced with the defined term, "Revolving Commitment
Maturity Date."

All other language in Section 2.01(e) remains unchanged.

        2.5    The defined term, "Maturity Date," is eliminated from
Section 2.02, and is replaced, in both instances in which it appears, with the
defined term, "Revolving Commitment Maturity Date."

All other language in Section 2.02 remains unchanged.

        2.6    The defined term, "Maturity Date," is eliminated from
Section 2.06(a), and is replaced, in both instances in which it appears, with
the defined term, "Additional Revolving Commitment Maturity Date."

All other language in Section 2.06(a) remains unchanged.

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        2.7    The defined term, "Maturity Date," is eliminated from
Section 2.07, and is replaced, in both instances in which it appears, with the
defined term, "Additional Revolving Commitment Maturity Date."

All other language in Section 2.07 remains unchanged.

        2.8    The $20,000,000 Revolving Note attached as Exhibit A to the
Agreement, and defined in Section 2.01(d) thereof, shall be replaced by the
Amended Revolving Note attached as Exhibit 1 hereto.

        2.9    The $15,000,000 Revolving Note attached as Exhibit B to the
Agreement, and defined in Section 2.06(d) thereof, shall be replaced by the
Amended Additional Revolving Note attached as Exhibit 2 hereto.

        2.10    Section 6.01(i) is amended to add the following language at the
conclusion thereof:

"Notwithstanding the foregoing provisions of this Section 6.01(i), Borrower
shall be permitted to utilize for its general corporate purposes, one hundred
percent (100%) of the net proceeds of Suburban's $15,000,000 private placement
of first mortgage bonds."

All other language in Section 6.01(i) remains unchanged.

        2.11    Schedule 6.02(e) attached to the Agreement is replaced in its
entirety with Amended Schedule 6.02(e), attached hereto as Exhibit 3.

        2.12    Section 6.02(e)(vi) is amended to add the following language at
the conclusion thereof:

"Notwithstanding the foregoing provisions of this Section 6.02(e)(vi), for the
time period ending November 30, 2004 only, the sum of $40,500,000 identified in
subsection (vi) of this Section 6.02(e), shall be increased to $44,500,000."

All other language in Section 6.02(e)(vi) remains unchanged.

        2.13    Section 6.02(g)(ii) is amended to add the following language as
the penultimate sentence thereof:

"For fiscal year 2004 only, however, Borrower may make Permitted Acquisitions
such that the aggregate consideration paid or payable by Borrower and its
Subsidiaries in connection with all Permitted Acquisitions shall not exceed
$10,200,000."

All other language in Section 6.02(g)(ii) remains unchanged.

        3.    Representations and Warranties.    When the Borrower signs this
Amendment, the Borrower represents and warrants to the Bank that: (a) there is
no event which is, or with notice or lapse of time or both would be, a default
under the Agreement except those events, if any, that have been disclosed in
writing to the Bank or waived in writing by the Bank, (b) the representations
and warranties in the Agreement are true as of the date of this Amendment as if
made on the date of this Amendment, and (c) this Amendment does not conflict
with any law, agreement, or obligation by which the Borrower is bound.

        4.    Conditions.    This Amendment will be effective when the Bank
receives in form and content acceptable to the Bank, this Amendment, duly
executed by Borrower.

        5.    Effect of Amendment.    Except as provided in this Amendment, all
of the terms and conditions of the Agreement shall remain in full force and
effect.

        6.    Counterparts.    This Amendment may be executed in counterparts,
each of which when so executed shall be deemed an original, but all such
counterparts together shall constitute but one and the same instrument.

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        This Amendment is executed as of the date stated at the beginning of
this Amendment.

BANK OF AMERICA, N.A.   SOUTHWEST WATER COMPANY
    
 
 
 
 
 
  By: /s/  [ILLEGIBLE]      

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  By: /s/  RICHARD SHIELDS      

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Name: [ILLEGIBLE]

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  Name: Approved: Richard Shields

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Title: SVP

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  Title: Chief Financial Officer

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Address:
 
Address:
Bank of America
675 Anton Boulevard, 2nd Floor
Costa Mesa, California 92626
Attention: Jamie L. Freeman
Title: Vice President
Facsimile: (714) 850-6586
 
One Wilshire Building
624 S. Grand Avenue, Suite 2900
Los Angeles, California 90017
Attention: Richard J. Shields
Chief Financial Officer
Facsimile: (213) 929-1888

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"EXHIBIT 3"

AMENDED SCHEDULE 6.02(c)—OTHER SECURED DEBT

Secured bank debt not to exceed $10,000,000, and other secured debt not to
exceed $55,000,000.

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EXHIBIT 1

AMENDED REVOLVING NOTE

$20,000,000   October 14, 2004

        FOR VALUE RECEIVED, the undersigned SOUTHWEST WATER COMPANY, a Delaware
corporation ("Borrower") promises to pay to the order of BANK OF AMERICA, N.A.
("Bank") at its office at 675 Anton Boulevard, 2nd Floor, Costa Mesa, California
92626, or at such other place as the holder hereof may designate, in lawful
money of the United States of America and in immediately available funds, the
principal sum of Twenty Million Dollars ($20,000,000), or so much thereof as may
be advanced and be outstanding, with interest thereon, to be computed on each
advance from the date of its disbursement (computed on the basis of a 360-day
year and actual days elapsed, which results in more interest than if a 365- day
year were used) at a rate per annum equal to the applicable LIBOR Rate plus one
and one-quarter percent (1.25%) or the Prime Rate minus one-quarter of one
percent (0.25%) with respect to all principal sums of less than Fifteen Million
Dollars ($15,000,000). When the aggregate principal sums outstanding are equal
to or greater than Fifteen Million Dollars ($15,000,000), the interest thereon
shall be computed at a rate per annum equal to the applicable LIBOR Rate plus
one and one-half percent (1.50%) or the Prime Rate with respect to the entire
principal sums outstanding (to be computed on each advance from the date of its
disbursement). When interest is determined in relation to the Prime Rate, each
change in the rate of interest hereunder shall become effective on the opening
of business on the day specified in the public announcement of a change in
Bank's Prime Rate. With respect to each LIBOR option selected hereunder, Bank is
hereby authorized to note the date, principal amount, interest rate and
applicable LIBOR Rate Term thereto and any payments made thereon on Bank's books
and records (either manually or by electronic entry) and/or on any schedule
attached to this Note, which notations shall be prima facie evidence of the
accuracy of the information noted.

A.    DEFINITIONS:    

        Capitalized terms used and not otherwise defined herein shall have the
meanings given such terms in the Credit Agreement referred to below. As used
herein, the following terms shall have the meanings set forth after each:

        1.     "Agreement" means that certain Credit Agreement between Borrower
and Bank dated as of October 6, 2003, as amended from time to time, including,
without limitation, those terms relating to arbitration of disputes.

        2.     "Amended and Restated Credit Agreement" means that certain
Amended and Restated Credit Agreement entered into between Borrower and Bank on
or about July 7, 2004, as amended from time to time.

        3.     "Business Day" means any day except a Saturday, Sunday or any
other day designated as a holiday under Federal or California statute or
regulation, or for amounts bearing interest based on the LIBOR Rate, any
Business Day is any day except a Saturday, Sunday or any other day designated as
a holiday under Federal or California statute or regulation on which dealings in
Dollar deposits are conducted by and among banks in the Designated LIBOR Market.

        4.     "Designated LIBOR Market" means the regular established market
located in London by and among banks for the solicitation, offer and acceptance
of Dollar deposits in such banks.

        5.     "Dollars" means United States of America dollars.

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        6.     "LIBOR Rate" means the interest rate determined by the following
formula, rounded upward, if necessary, to the nearest 1/100 of one percent. (All
amounts in the calculation will be determined by Bank as of the first day of the
interest period.)

LIBOR Rate =   LIBOR   Base   Rate    

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    (1.00 - Reserve Percentage)        

        (a)   "LIBOR Base Rate" means, with respect to any Revolving Loan to be
made by Bank which is to bear interest in relation to the LIBOR Rate, the
interest rate per annum (rounded upward, if necessary, to the nearest 1/100th of
1%) at which deposits in Dollars are offered by Bank through its London Banking
Center, London, Great Britain to prime banks in the Designated LIBOR Market on
the first day of the applicable LIBOR Rate Term in an aggregate amount
approximately equal to the amount of the Revolving Loan to be made by Bank and
for a period of time comparable to the number of days in the applicable LIBOR
Rate Term. The determination of the LIBOR Base Rate by Bank shall be conclusive
in the absence of manifest error.

        (b)   "Reserve Percentage" means, with respect to any Revolving Loan to
be made by Bank which is to bear interest in relation to the LIBOR Rate, the
maximum reserve percentage (expressed as a decimal, rounded upward, if
necessary, to the nearest 1/100 of one percent) in effect on the date the LIBOR
Base Rate for the Revolving Loan is determined (whether or not such reserve
percentage is applicable to Bank) under regulations issued from time to time by
the Federal Reserve Board for determining the maximum reserve requirement
(including any emergency, supplemental or other marginal reserve requirement)
with respect to eurocurrency funding (currently referred to as "eurocurrency
liabilities") having a term comparable to the LIBOR Rate Term for such Revolving
Loan. The determination by Bank of any applicable Reserve Percentage shall be
conclusive in the absence of manifest error.

        7.     "LIBOR Rate Portion" means a portion of the principal amount
outstanding under this Note which is bearing interest at a rate related to
LIBOR. No LIBOR Rate Portion shall be less than Two Hundred Fifty Thousand
Dollars ($250,000).

        8.     "LIBOR Rate Term" means a period commencing on a Business Day and
continuing for one (1) month, two (2) months, three (3) months, six (6) months
or twelve (12) months, as designated by Borrower, during which all or a portion
of the outstanding principal balance of this Note bears interest determined in
relation to Bank's LIBOR; provided however, that no LIBOR Rate Term shall extend
beyond the scheduled maturity date hereof. The last day of the interest period
will be determined by Bank using the Designated LIBOR Market. If any LIBOR Rate
Term would end on a day which is not a Business Day, then such LIBOR Rate Term
shall be extended to the next succeeding Business Day.

        9.     "Prime Rate" means the rate of interest publicly announced from
time to time by the Bank as its Prime Rate. The Prime Rate is set by the Bank
based on various factors, including the Bank's costs and desired return, general
economic conditions and other factors, and is used as a reference point for
pricing some loans. The Bank may price loans to its customers at, above or below
the Prime Rate. Any change in the Prime Rate will take effect at the opening of
business on the day specified in the public announcement of a change in the
Bank's Prime Rate.

B.    INTEREST:    

        1.    Payment of Interest.    Interest accrued on this Note shall be
payable on the fifteenth (15th) day of each month for the prior month or portion
thereof, commencing June 15, 2004.

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        2.    Selection of Interest Rate Options.    At any time any portion of
this Note bears interest determined in relation to the LIBOR Rate, it may be
continued by Borrower at the end of the LIBOR Rate Term applicable thereto so
that all or a portion thereof bears interest determined in relation to the Prime
Rate or in relation to the LIBOR Rate for a new LIBOR Rate Term designated by
Borrower. At any time any portion of this Note bears interest determined in
relation to the Prime Rate, Borrower may convert all or a portion thereof so
that it bears interest determined in relation to the LIBOR Rate for a LIBOR Rate
Term designated by Borrower. At the time each advance is requested hereunder or
Borrower wishes to select the LIBOR option for all or a portion of the
outstanding principal balance hereof, and at the end of each LIBOR Rate Term,
Borrower shall give Bank notice specifying (a) the interest rate option selected
by Borrower, (b) the principal amount subject thereto, and (c) if the LIBOR
option is selected, the length of the applicable LIBOR Rate Term. Any such
notice may be given by telephone so long as, with respect to each LIBOR
selection, such notice is given to Bank prior to 10:00 a.m., California time, on
the third Business Day prior to the commencement of the LIBOR Rate Term and,
with respect to each Prime Rate selection, such notice is given to Bank prior to
11:00 a.m., California time, on the day of the requested advance. For each LIBOR
option requested hereunder, Bank will quote the applicable LIBOR Rate to
Borrower at approximately 10:00 a.m., California time, on the second Business
Day prior to the LIBOR Rate Term. If Borrower does not immediately accept the
rate quoted by Bank, any subsequent acceptance by Borrower shall be subject to a
re-determination by Bank of the applicable LIBOR Rate; provided however, that if
Borrower fails to accept any such rate by 11:00 a.m., California time, on the
Business Day such quotation is given, then the quoted rate shall expire and Bank
shall have no obligation to permit a LIBOR option to be selected on such day. If
no specific designation of interest is made at the time any advance is requested
hereunder or at the end of any LIBOR Rate Term, Borrower shall be deemed to have
made a Prime Rate interest selection for such advance or the principal amount to
which such LIBOR Rate Term applied.

        3.    Additional LIBOR Provisions.    

        (a)   If Bank at any time shall determine that for any reason adequate
and reasonable means do not exist for ascertaining the LIBOR Rate, then Bank
shall promptly give notice thereof to Borrower. If such notice is given and
until such notice has been withdrawn by Bank, then (i) no new LIBOR option may
be selected by Borrower, and (ii) any portion of the outstanding principal
balance hereof which bears interest determined in relation to the LIBOR Rate,
subsequent to the end of the LIBOR Rate Term applicable thereto, shall bear
interest determined in relation to the Prime Rate.

        (b)   If any law, treaty, rule, regulation or determination of a court
or governmental authority or any change therein or in the interpretation or
application thereof (each, a "Change in Law") shall make it unlawful for Bank
(i) to make LIBOR options available hereunder, or (ii) to maintain interest
rates based on the LIBOR Rate, then in the former event, any obligation of Bank
to make available such unlawful LIBOR options shall immediately be cancelled,
and in the latter event, any such unlawful LIBOR-based interest rates then
outstanding shall be converted, at Bank's option, so that interest on the
portion of the outstanding principal balance subject thereto is determined in
relation to the Prime Rate; provided however, that if any such Change in Law
shall permit any LIBOR-based interest rates to remain in effect until the
expiration of the LIBOR Rate Term applicable thereto, then such permitted
LIBOR-based interest rates shall continue in effect until the expiration of such
LIBOR Rate Term. Upon the occurrence of any of the foregoing events, Borrower
shall pay to Bank immediately upon demand such amounts as may be necessary to
compensate Bank for any fines, fees, charges, penalties or other costs incurred
or payable by Bank as a result thereof and which are attributable to any LIBOR
options made available to Borrower hereunder, and any reasonable allocation made
by Bank among its operations shall be conclusive and binding upon Borrower.

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        (c)   If any Change in Law or compliance by Bank with any request or
directive (whether or not having the force of law) from any central bank or
other governmental authority shall:

          (i)  subject Bank to any tax, duty or other charge with respect to any
LIBOR options, or change the basis of taxation of payments to Bank of principal,
interest, fees or any other amount payable hereunder (except for changes, in the
rate of tax on the overall net income of Bank); or

         (ii)  impose, modify or hold applicable any reserve, special deposit,
compulsory loan or similar requirement against assets held by, deposits or other
liabilities in or for the account of advances or loans by, or any other
acquisition of funds by any office of Bank; or

        (iii)  impose on Bank any other condition; and the result of any of the
foregoing is to increase the cost to Bank of making, renewing or maintaining any
LIBOR options hereunder and/or to reduce any amount receivable by Bank in
connection therewith, then in any such case, Borrower shall pay to Bank
immediately upon demand such amounts as may be necessary to compensate Bank for
any additional costs incurred by Bank and/or reductions in amounts received by
Bank which are attributable to such LIBOR options. In determining which costs
incurred by Bank and/or reductions in amounts received by Bank are attributable
to any LIBOR options made available to Borrower hereunder, any reasonable
allocation made by Bank among its operations shall be conclusive and binding
upon Borrower.

        (d)   Bank will have no obligation to accept an election of Borrower for
the LIBOR option if any of the following described events has occurred and is
continuing:

          (i)  Dollar deposits in the principal amount, and for periods equal to
the LIBOR Rate Term, of any Revolving Loan which bears interest in relation to
the LIBOR Rate are not available in the Designated LIBOR Market; or

         (ii)  an Event of Default has occurred and is continuing; or

        (iii)  the LIBOR Rate does not accurately reflect the cost of any
Revolving Loan which bears interest in relation to the LIBOR Rate.

        4.    Default Interest.    During the continuance of an Event of
Default, the outstanding principal balance of this Note shall bear interest
until paid in full at an increased rate per annum (computed on the basis of a
360-day year and actual days elapsed, which results in more interest than if a
365-day year were used) equal to two percent (2.00%) above the rate of interest
from time to time applicable to this Note (the "Default Rate").

C.    BORROWING AND REPAYMENT:    

        1.    Loan and Repayment.    Borrower may from time to time during the
term of this Note borrow, partially or wholly repay its outstanding borrowings,
and re-borrow, subject to all of the limitations, terms and conditions of this
Note and of any document executed in connection with or governing this Note,
including the Amended and Restated Credit Agreement; provided however, that the
total outstanding borrowings under this Note shall not at any time exceed the
principal amount stated above. The unpaid principal balance of this obligation
at any time shall be the total amounts advanced hereunder by the holder hereof
less the amount of principal payments made hereon by or for Borrower, which
balance may be endorsed hereon from time to time by the holder. The outstanding
principal balance of this Note shall be due and payable in full on the
"Revolving Commitment Maturity Date" (as defined in the Amended and Restated
Credit Agreement as amended from time to time.)

        2.    Advances.    Advances hereunder, to the total amount of the
principal sum stated above, may be made by the holder at the oral or written
request of (a) Richard Shields, who is authorized to request advances and direct
the disposition of any advances until written notice of the revocation of

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such authority is received by the holder at the office designated above, or
(b) any person, with respect to advances deposited to the credit of any account
of Borrower with the holder, which advances, when so deposited, shall be
conclusively presumed to have been made to or for the benefit of Borrower
regardless of the fact that persons other than those authorized to request
advances may have authority to draw against such account. The holder shall have
no obligation to determine whether any person requesting an advance is or has
been authorized by Borrower.

        3.    Application of Payments.    Each payment made on this Note shall
be credited first, to any interest then due and second, to the outstanding
principal balance hereof. Unless instructed otherwise by Borrower, all payments
credited to principal shall be applied first, to the outstanding principal
balance of this Note which bears interest determined in relation to the Prime
Rate, if any, and second, to the outstanding principal balance of this Note
which bears interest determined in relation to the LIBOR Rate, with such
payments applied to the oldest LIBOR Rate Term first.

        4.    Prepayment.    

        (a)    Prime Rate.    Borrower may prepay principal on any portion of
this Note which bears interest determined in relation to the Prime Rate at any
time, in any amount and without penalty.

        (b)    LIBOR.    Each prepayment of a LIBOR Rate Portion shall be not
less than $250,000 and shall be in an integral multiple of $100,000, and Bank
shall have received notice of each such prepayment on the date that is five
(5) Business Days before the date of such prepayment (which notice shall
identify the date and amount of the prepayment). Each prepayment of a LIBOR Rate
Portion, whether voluntary, by reason of acceleration or otherwise, will be
accompanied by the amount of accrued interest on the amount prepaid, and a
prepayment fee as described below. A "prepayment" is a payment on a date earlier
than the last day of the applicable LIBOR Rate Term. The prepayment fee shall be
equal to the amount (if any) by which:

          (i)  the additional interest which would have been payable during the
applicable LIBOR Rate Term on the amount prepaid had it not been prepaid,
exceeds

         (ii)  the interest which would have been recoverable by Bank by placing
the amount prepaid on deposit in the domestic certificate of deposit market, the
eurodollar deposit market, or other appropriate money market selected by Bank
for a period starting on the date on which it was prepaid and ending on the last
day of the applicable LIBOR Rate Term.

Borrower acknowledges that prepayment of such amount may result in Bank
incurring additional costs, expenses and/or liabilities, and that it is
difficult to ascertain the full extent of such costs, expenses and/or
liabilities. Borrower, therefore, agrees to pay the above-described prepayment
fee and agrees that said amount represents a reasonable estimate of the
prepayment costs, expenses and/or liabilities of Bank. If Borrower fails to pay
any prepayment fee when due, the amount of such prepayment fee shall thereafter
bear interest until paid at a rate per annum two percent (2.00%) above the Prime
Rate in effect from time to time (computed on the basis of a 360-day year,
actual days elapsed).

D.    EVENTS OF DEFAULT:    

        This Note is made pursuant to and is subject to the terms and conditions
of the Amended and Restated Credit Agreement. Any default in the payment or
performance of any obligation under this Note, or any defined event of default
under the Amended and Restated Credit Agreement, shall constitute an "Event of
Default" under this Note.

E.    MISCELLANEOUS:    

        1.    Remedies.    Upon the occurrence of any Event of Default, the
holder of this Note, at the holder's option, without notice upon the occurrence
of an Event of Default pursuant to Section 7.01(g) of the Amended and Restated
Credit Agreement, and with notice upon the occurrence of any other

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Event of Default, may declare all sums of principal and interest outstanding
hereunder to be immediately due and payable without presentment, demand, protest
or notice of dishonor, all of which are expressly waived by Borrower, and the
obligation, if any, of the holder to extend any further credit hereunder shall
immediately cease and terminate. Borrower shall pay to the holder immediately
upon demand the full amount of all payments, advances, charges, costs and
expenses, including reasonable attorneys' fees (to include outside counsel fees
and all allocated costs of the holder's in-house counsel), incurred by the
holder in connection with the enforcement of the holder's rights and/or the
collection of any amounts which become due to the holder under this Note, and
the prosecution or defense of any action in any way related to this Note,
including without limitation, any action for declaratory relief, and including
any of the foregoing incurred in connection with any bankruptcy proceeding
relating to Borrower.

        2.    Obligations Joint and Several.    Should more than one person or
entity sign this Note as a Borrower, the obligations of each such Borrower shall
be joint and several.

        3.    Governing Law.    This Note shall be governed by and construed in
accordance with the laws of the State of California, except to the extent Bank
has greater rights or remedies under Federal law, whether as a national bank or
otherwise, in which case such choice of California law shall not be deemed to
deprive Bank of any such rights and remedies as may be available under Federal
law.

    "Borrower"
 
 
SOUTHWEST WATER COMPANY,
a Delaware corporation
    
 
 
 
      By: /s/  RICHARD SHIELDS      

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    Name: Approved: Richard Shields

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    Title: Chief Financial Officer

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EXHIBIT 2

AMENDED ADDITIONAL REVOLVING NOTE

$15,000,000   October 14, 2004

        FOR VALUE RECEIVED, the undersigned SOUTHWEST WATER COMPANY, a Delaware
corporation ("Borrower") promises to pay to the order of BANK OF AMERICA, N.A.
("Bank") at its office at 675 Anton Boulevard, 2nd Floor, Costa Mesa, California
92626, or at such other place as the holder hereof may designate, in lawful
money of the United States of America and in immediately available funds, the
principal sum of Fifteen Million Dollars ($15,000,000), or so much thereof as
may be advanced and be outstanding, with interest thereon, to be computed on
each advance from the date of its disbursement (computed on the basis of a
360-day year and actual days elapsed, which results in more interest than if a
365-day year were used) at a rate per annum equal to the applicable LIBOR Rate
plus two and one-half percent (2.5%) or the Prime Rate. When interest is
determined in relation to the Prime Rate, each change in the rate of interest
hereunder shall become effective on the opening of business on the day specified
in the public announcement of a change in Bank's Prime Rate. With respect to
each LIBOR option selected hereunder, Bank is hereby authorized to note the
date, principal amount, interest rate and applicable LIBOR Rate Term thereto and
any payments made thereon on Bank's books and records (either manually or by
electronic entry) and/or on any schedule attached to this Note, which notations
shall be prima facie evidence of the accuracy of the information noted.

A.    DEFINITIONS:    

        Capitalized terms used and not otherwise defined herein shall have the
meanings given such terms in the Credit Agreement referred to below. As used
herein, the following terms shall have the meanings set forth after each:

        1.     "Amended and Restated Credit Agreement" means that certain
Amended and Restated Credit Agreement entered into between Borrower and Bank on
or about July 7, 2004, as amended from time to time.

        2.     "Business Day" means any day except a Saturday, Sunday or any
other day designated as a holiday under Federal or California statute or
regulation, or for amounts bearing interest based on the LIBOR Rate, any
Business Day is any day except a Saturday, Sunday or any other day designated as
a holiday under Federal or California statute or regulation on which dealings in
Dollar deposits are conducted by and among banks in the Designated LIBOR Market.

        3.     "Designated LIBOR Market" means the regular established market
located in London by and among banks for the solicitation, offer and acceptance
of Dollar deposits in such banks.

        4.     "Dollars" means United States of America dollars.

        5.     "LIBOR Rate" means the interest rate determined by the following
formula, rounded upward, if necessary, to the nearest 1/100 of one percent. (All
amounts in the calculation will be determined by Bank as of the first day of the
interest period.)

LIBOR Rate =   LIBOR   Base   Rate    

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    (1.00 - Reserve Percentage)        

        (a)   "LIBOR Base Rate" means, with respect to any Additional Revolving
Loan to be made by Bank which is to bear interest in relation to the LIBOR Rate,
the interest rate per annum (rounded upward, if necessary, to the nearest
1/100th of 1%) at which deposits in Dollars are offered by Bank through its
London Banking Center, London, Great Britain to prime banks in the Designated
LIBOR Market on the first day of the applicable LIBOR Rate

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Term in an aggregate amount approximately equal to the amount of the Revolving
Loan to be made by Bank and for a period of time comparable to the number of
days in the applicable LIBOR Rate Term. The determination of the LIBOR Base Rate
by Bank shall be conclusive in the absence of manifest error.

        (b)   "Reserve Percentage" means, with respect to any Additional
Revolving Loan to be made by Bank which is to bear interest in relation to the
LIBOR Rate, the maximum reserve percentage (expressed as a decimal, rounded
upward, if necessary, to the nearest 1/100 of one percent) in effect on the date
the LIBOR Base Rate for the Revolving Loan is determined (whether or not such
reserve percentage is applicable to Bank) under regulations issued from time to
time by the Federal Reserve Board for determining the maximum reserve
requirement (including any emergency, supplemental or other marginal reserve
requirement) with respect to eurocurrency funding (currently referred to as
"eurocurrency liabilities") having a term comparable to the LIBOR Rate Term for
such Revolving Loan. The determination by Bank of any applicable Reserve
Percentage shall be conclusive in the absence of manifest error.

        6.     "LIBOR Rate Portion" means a portion of the principal amount
outstanding under this Note which is bearing interest at a rate related to
LIBOR. No LIBOR Rate Portion shall be less than Two Hundred Fifty Thousand
Dollars ($250,000).

        7.     "LIBOR Rate Term" means a period commencing on a Business Day and
continuing for one (1) month, two (2) months, three (3) months, six (6) months
or twelve (12) months, as designated by Borrower, during which all or a portion
of the outstanding principal balance of this Note bears interest determined in
relation to Bank's LIBOR; provided however, that no LIBOR Rate Term shall extend
beyond the scheduled maturity date hereof. The last day of the interest period
will be determined by Bank using the Designated LIBOR Market. If any LIBOR Rate
Term would end on a day which is not a Business Day, then such LIBOR Rate Term
shall be extended to the next succeeding Business Day.

        8.     "Prime Rate" means the rate of interest publicly announced from
time to time by the Bank as its Prime Rate. The Prime Rate is set by the Bank
based on various factors, including the Bank's costs and desired return, general
economic conditions and other factors, and is used as a reference point for
pricing some loans. The Bank may price loans to its customers at, above or below
the Prime Rate. Any change in the Prime Rate will take effect at the opening of
business on the day specified in the public announcement of a change in the
Bank's Prime Rate.

B.    INTEREST:    

        1.    Payment of Interest.    Interest accrued on this Note shall be
payable on the fifteenth (15th) day of each month for the prior month or portion
thereof, commencing August 15, 2004.

        2.    Selection of Interest Rate Options.    At any time any portion of
this Note bears interest determined in relation to the LIBOR Rate, it may be
continued by Borrower at the end of the LIBOR Rate Term applicable thereto so
that all or a portion thereof bears interest determined in relation to the Prime
Rate or in relation to the LIBOR Rate for a new LIBOR Rate Term designated by
Borrower. At any time any portion of this Note bears interest determined in
relation to the Prime Rate, Borrower may convert all or a portion thereof so
that it bears interest determined in relation to the LIBOR Rate for a LIBOR Rate
Term designated by Borrower. At the time each advance is requested hereunder or
Borrower wishes to select the LIBOR option for all or a portion of the
outstanding principal balance hereof, and at the end of each LIBOR Rate Term,
Borrower shall give Bank notice specifying (a) the interest rate option selected
by Borrower, (b) the principal amount subject thereto, and (c) if the LIBOR
option is selected, the length of the applicable LIBOR Rate Term. Any such
notice may be given by telephone so long as, with respect to each LIBOR
selection, such notice is given to Bank prior to 10:00 a.m., California time, on
the third Business Day prior to the

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commencement of the LIBOR Rate Term and, with respect to each Prime Rate
selection, such notice is given to Bank prior to 11:00 a.m., California time, on
the day of the requested advance. For each LIBOR option requested hereunder,
Bank will quote the applicable LIBOR Rate to Borrower at approximately
10:00 a.m., California time, on the second Business Day prior to the LIBOR Rate
Term. If Borrower does not immediately accept the rate quoted by Bank, any
subsequent acceptance by Borrower shall be subject to a re-determination by Bank
of the applicable LIBOR Rate; provided however, that if Borrower fails to accept
any such rate by 11:00 a.m., California time, on the Business Day such quotation
is given, then the quoted rate shall expire and Bank shall have no obligation to
permit a LIBOR option to be selected on such day. If no specific designation of
interest is made at the time any advance is requested hereunder or at the end of
any LIBOR Rate Term, Borrower shall be deemed to have made a Prime Rate interest
selection for such advance or the principal amount to which such LIBOR Rate Term
applied.

        3.    Additional LIBOR Provisions.    

        (a)   If Bank at any time shall determine that for any reason adequate
and reasonable means do not exist for ascertaining the LIBOR Rate, then Bank
shall promptly give notice thereof to Borrower. If such notice is given and
until such notice has been withdrawn by Bank, then (i) no new LIBOR option may
be selected by Borrower, and (ii) any portion of the outstanding principal
balance hereof which bears interest determined in relation to the LIBOR Rate,
subsequent to the end of the LIBOR Rate Term applicable thereto, shall bear
interest determined in relation to the Prime Rate.

        (b)   If any law, treaty, rule, regulation or determination of a court
or governmental authority or any change therein or in the interpretation or
application thereof (each, a "Change in Law") shall make it unlawful for Bank
(i) to make LIBOR options available hereunder, or (ii) to maintain interest
rates based on the LIBOR Rate, then in the former event, any obligation of Bank
to make available such unlawful LIBOR options shall immediately be cancelled,
and in the latter event, any such unlawful LIBOR-based interest rates then
outstanding shall be converted, at Bank's option, so that interest on the
portion of the outstanding principal balance subject thereto is determined in
relation to the Prime Rate; provided however, that if any such Change in Law
shall permit any LIBOR-based interest rates to remain in effect until the
expiration of the LIBOR Rate Term applicable thereto, then such permitted
LIBOR-based interest rates shall continue in effect until the expiration of such
LIBOR Rate Term. Upon the occurrence of any of the foregoing events, Borrower
shall pay to Bank immediately upon demand such amounts as may be necessary to
compensate Bank for any fines, fees, charges, penalties or other costs incurred
or payable by Bank as a result thereof and which are attributable to any LIBOR
options made available to Borrower hereunder, and any reasonable allocation made
by Bank among its operations shall be conclusive and binding upon Borrower.

        (c)   If any Change in Law or compliance by Bank with any request or
directive (whether or not having the force of law) from any central bank or
other governmental authority shall:

          (i)  subject Bank to any tax, duty or other charge with respect to any
LIBOR options, or change the basis of taxation of payments to Bank of principal,
interest, fees or any other amount payable hereunder (except for changes in the
rate of tax on the overall net income of Bank); or

         (ii)  impose, modify or hold applicable any reserve, special deposit,
compulsory loan or similar requirement against assets held by, deposits or other
liabilities in or for the account of advances or loans by, or any other
acquisition of funds by any office of Bank; or

        (iii)  impose on Bank any other condition; and the result of any of the
foregoing is to increase the cost to Bank of making, renewing or maintaining any
LIBOR options hereunder

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and/or to reduce any amount receivable by Bank in connection therewith, then in
any such case, Borrower shall pay to Bank immediately upon demand such amounts
as may be necessary to compensate Bank for any additional costs incurred by Bank
and/or reductions in amounts received by Bank which are attributable to such
LIBOR options. In determining which costs incurred by Bank and/or reductions in
amounts received by Bank are attributable to any LIBOR options made available to
Borrower hereunder, any reasonable allocation made by Bank among its operations
shall be conclusive and binding upon Borrower.

        (d)   Bank will have no obligation to accept an election of Borrower for
the LIBOR option if any of the following described events has occurred and is
continuing:

          (i)  Dollar deposits in the principal amount, and for periods equal to
the LIBOR Rate Term, of any Revolving Loan which bears interest in relation to
the LIBOR Rate are not available in the Designated LIBOR Market; or

         (ii)  an Event of Default has occurred and is continuing; or

        (iii)  the LIBOR Rate does not accurately reflect the cost of any
Revolving Loan which bears interest in relation to the LIBOR Rate.

        4.    Default Interest.    During the continuance of an Event of
Default, the outstanding principal balance of this Note shall bear interest
until paid in full at an increased rate per annum (computed on the basis of a
360-day year and actual days elapsed, which results in more interest than if a
365-day year were used) equal to two percent (2.00%) above the rate of interest
from time to time applicable to this Note (the "Default Rate").

C.    BORROWING AND REPAYMENT:    

        1.    Loan and Repayment.    Borrower may from time to time during the
term of this Note borrow, partially or wholly repay its outstanding borrowings,
and re-borrow, subject to all of the limitations, terms and conditions of this
Note and of any document executed in connection with or governing this Note,
including the Amended and Restated Credit Agreement; provided however, that the
total outstanding borrowings under this Note shall not at any time exceed the
principal amount stated above. The unpaid principal balance of this obligation
at any time shall be the total amounts advanced hereunder by the holder hereof
less the amount of principal payments made hereon by or for Borrower, which
balance may be endorsed hereon from time to time by the holder. The outstanding
principal balance of this Note shall be due and payable in full on the
"Additional Revolving Commitment Maturity Date" (as defined in the Amended and
Restated Credit Agreement as amended from time to time.)

        2.    Advances.    Advances hereunder, to the total amount of the
principal sum stated above, may be made by the holder at the oral or written
request of (a) Richard Shields, who is authorized to request advances and direct
the disposition of any advances until written notice of the revocation of such
authority is received by the holder at the office designated above, or (b) any
person, with respect to advances deposited to the credit of any account of
Borrower with the holder, which advances, when so deposited, shall be
conclusively presumed to have been made to or for the benefit of Borrower
regardless of the fact that persons other than those authorized to request
advances may have authority to draw against such account. The holder shall have
no obligation to determine whether any person requesting an advance is or has
been authorized by Borrower.

        3.    Application of Payments.    Each payment made on this Note shall
be credited first, to any interest then due and second, to the outstanding
principal balance hereof. Unless instructed otherwise by Borrower, all payments
credited to principal shall be applied first, to the outstanding principal
balance of this Note which bears interest determined in relation to the Prime
Rate, if any, and second,

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to the outstanding principal balance of this Note which bears interest
determined in relation to the LIBOR Rate, with such payments applied to the
oldest LIBOR Rate Term first.

        4.    Prepayment.    

        (a)    Prime Rate.    Borrower may prepay principal on any portion of
this Note which bears interest determined in relation to the Prime Rate at any
time, in any amount and without penalty.

        (b)    LIBOR.    Each prepayment of a LIBOR Rate Portion shall be not
less than $250,000 and shall be in an integral multiple of $100,000, and Bank
shall have received notice of each such prepayment on the date that is five
(5) Business Days before the date of such prepayment (which notice shall
identify the date and amount of the prepayment). Each prepayment of a LIBOR Rate
Portion, whether voluntary, by reason of acceleration or otherwise, will be
accompanied by the amount of accrued interest on the amount prepaid, and a
prepayment fee as described below. A "prepayment" is a payment on a date earlier
than the last day of the applicable LIBOR Rate Term. The prepayment fee shall be
equal to the amount (if any) by which:

          (i)  the additional interest which would have been payable during the
applicable LIBOR Rate Term on the amount prepaid had it not been prepaid,
exceeds

         (ii)  the interest which would have been recoverable by Bank by placing
the amount prepaid on deposit in the domestic certificate of deposit market, the
eurodollar deposit market, or other appropriate money market selected by Bank
for a period starting on the date on which it was prepaid and ending on the last
day of the applicable LIBOR Rate Term.

Borrower acknowledges that prepayment of such amount may result in Bank
incurring additional costs, expenses and/or liabilities, and that it is
difficult to ascertain the full extent of such costs, expenses and/or
liabilities. Borrower, therefore, agrees to pay the above-described prepayment
fee and agrees that said amount represents a reasonable estimate of the
prepayment costs, expenses and/or liabilities of Bank. If Borrower fails to pay
any prepayment fee when due, the amount of such prepayment fee shall thereafter
bear interest until paid at a rate per annum two percent (2.00%) above the Prime
Rate in effect from time to time (computed on the basis of a 360-day year,
actual days elapsed).

D.    EVENTS OF DEFAULT:    

        This Note is made pursuant to and is subject to the terms and conditions
of the Amended and Restated Credit Agreement. Any default in the payment or
performance of any obligation under this Note, or any defined event of default
under the Amended and Restated Credit Agreement, shall constitute an "Event of
Default" under this Note.

E.    MISCELLANEOUS:    

        1.    Remedies.    Upon the occurrence of any Event of Default, the
holder of this Note, at the holder's option, without notice upon the occurrence
of an Event of Default pursuant to Section 7.01(g) of the Amended and Restated
Credit Agreement, and with notice upon the occurrence of any other Event of
Default, may declare all sums of principal and interest outstanding hereunder to
be immediately due and payable without presentment, demand, protest or notice of
dishonor, all of which are expressly waived by Borrower, and the obligation, if
any, of the holder to extend any further credit hereunder shall immediately
cease and terminate. Borrower shall pay to the holder immediately upon demand
the full amount of all payments, advances, charges, costs and expenses,
including reasonable attorneys' fees (to include outside counsel fees and all
allocated costs of the holder's in-house counsel), incurred by the holder in
connection with the enforcement of the holder's rights and/or the collection of
any amounts which become due to the holder under this Note, and the prosecution
or defense of any action in any way related to this Note, including without
limitation, any action for declaratory relief, and including any of the
foregoing incurred in connection with any bankruptcy proceeding relating to
Borrower.

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        2.    Obligations Joint and Several.    Should more than one person or
entity sign this Note as a Borrower, the obligations of each such Borrower shall
be joint and several.

        3.    Governing Law.    This Note shall be governed by and construed in
accordance with the laws of the State of California, except to the extent Bank
has greater rights or remedies under Federal law, whether as a national bank or
otherwise, in which case such choice of California law shall not be deemed to
deprive Bank of any such rights and remedies as may be available under Federal
law.

    "Borrower"
 
 
SOUTHWEST WATER COMPANY,
a Delaware corporation
    
 
 
 
      By: /s/  RICHARD SHIELDS      

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    Name: Approved: Richard Shields

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    Title: Chief Financial Officer

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ACKNOWLEDGMENT REGARDING INTERCREDITOR AND PLEDGE AGREEMENTS

        The undersigned, in its capacity as a party to each of (i) the
Intercreditor Agreement, dated as of July 14, 2004, by and among the
undersigned, Union Bank of California, N.A. and Union Bank of California, N.A.,
as Collateral Agent (the "Intercreditor Agreement"), and (ii) the Pledge and
Collateral Agency Agreement, dated as of July 14, 2004, by and among Southwest
Water Company, the undersigned, Union Bank of California, N.A. and Union Bank of
California, N.A., as Collateral Agent (the "Pledge Agreement"), hereby
acknowledges and consents to the waivers and modifications to the Credit
Agreement contained in the attached Waiver and Amendment and agrees that both
the Intercreditor Agreement and the Pledge Agreement shall remain in full force
and effect notwithstanding the Waiver and Amendment.

    BANK OF AMERICA, N.A.
    
 
 
      By: /s/  ANNA C. RUIZ      

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Anna C. Ruiz
Vice President

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QuickLinks

AMENDMENT NO. 1 TO AMENDED AND RESTATED CREDIT AGREEMENT
EXHIBIT 1

EXHIBIT 2