THIRD AMENDMENT AND SUPPLEMENT TO INDENTURE OF MORTGAGE DATED FEBRUARY 14, 1992

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Exhibit 4.6d

RECORDING REQUESTED BY, AND
WHEN RECORDED, MAIL TO:

Sosi Biricik
Latham & Watkins LLP
600 West Broadway, Suite 1800
San Diego, California 92101-3375

INSTRUCTIONS TO COUNTY RECORDER:

Index this instrument as:

(i)

a Mortgage;

(ii)

a Fixture Filing; and

(iii)

a Deed of Trust.

NEW MEXICO UTILITIES, INC.

TO

WELLS FARGO BANK, N.A.,

TRUSTEE

THIRD AMENDMENT AND SUPPLEMENT TO INDENTURE OF MORTGAGE DATED FEBRUARY 14, 1992

[The Indenture to which this instrument is a supplement is a mortgage of both real and personal property, including chattels, and also constitutes, among other things, a security agreement creating a security interest in personal property. Such Indenture contains after-acquired property provisions. Such Indenture also contains an Agreement, in Section 9.04 thereof, by which New Mexico Utilities, Inc., as trustor, agrees to subject the real estate subject thereto to the terms of the Deed of Trust Act 48-10-1 to 48-10-21 NMSA 1978.]

        THIS THIRD AMENDMENT AND SUPPLEMENT TO INDENTURE OF MORTGAGE DATED FEBRUARY 14, 1992 (the "Third Amendment" ), is made and entered into as of December 15, 2004, by and between NEW MEXICO UTILITIES, INC., a New Mexico corporation (the "Company" ), and WELLS FARGO BANK, N.A., a national banking association (the "Trustee" ), with respect to the following:

RECITALS

        A.    The Company executed that certain Indenture of Mortgage dated February 14, 1992 (the "Original Indenture" ) to Sunwest Bank of Albuquerque, National Association, which later became Nations Bank, N.A., a national banking association, as trustee, predecessor to Norwest Bank New Mexico, N.A., predecessor to Wells Fargo Bank New Mexico, N.A., predecessor to the Trustee. The Original Indenture was filed on March 31, 1992, as Document No. 92-222404, recorded in Book 92-5, Pages 9251 to 9380 in the Records of the County of Bernalillo, State of New Mexico.

        B.    The Original Indenture was amended pursuant to (i) that certain First Supplement to Indenture of Mortgage dated February 14, 1992 (the "First Amendment" ) dated as of May 15, 1992 and filed on July 8, 1992 as Document No. 92-68584, recorded in Book 92-16, Pages 1502-1508 in the Records of the County of Bernalillo, State of New Mexico and (ii) that certain Second Amendment and Supplement to Indenture of Mortgage dated February 14, 1992 (the "Second Amendment" ) dated as of October 21, 1996 and filed on November 4, 1996 as Document No. 96-120516, recorded in Book 96-29, Pages 6363-6385 in the Records of the County of Bernalillo, State of New Mexico. The Original Indenture, as amended and supplemented by the First Amendment and the Second Amendment, is hereinafter referred to as the "Existing Indenture," and the Existing Indenture as amended and supplemented by this Third Amendment is hereinafter referred to as the "Indenture."

        C.    The Company has requested that the Trustee enter into this Third Amendment setting forth the terms and conditions of the issuance of certain Bonds in the aggregate principal amount of $12,000,000, which Bonds shall be issued as "Series C" under and pursuant to the Indenture.

        D.    The Company has duly authorized the creation, execution and delivery of the Series C Bonds, and all things have been done which are necessary to make the Series C Bonds, when executed by the Company and authenticated and delivered by the Trustee under the Indenture and duly issued by the Company, the valid and binding obligations of the Company, and to constitute the Indenture a valid mortgage and deed of trust and a security agreement and contract for the security of the Bonds (including, without limitation, the Series C Bonds), in accordance with the terms of the Bonds and the Indenture. In addition, all other instruments and actions required pursuant to law and pursuant to the requirements of the Existing Indenture for the Trustee to execute and deliver this Third Amendment have been duly delivered or taken.

AMENDMENT

        IN CONSIDERATION of the foregoing recitals and pursuant to the authority granted under Section 13.01 of the Existing Indenture [Supplemental Indentures Without Consent of Bondholders], the Company and the Trustee agree that the Existing Indenture shall be amended in the following respects:

1.     DEFINITIONS.

        All terms used in this Third Amendment with initial capital letters and not defined herein shall have the meanings given to them in the Existing Indenture.

2.     GRANT OF REAL PROPERTY.

(a)

By its signature hereto, and to secure the payment of the principal of (and Make-Whole Amount, if any) and interest on the Outstanding Secured Bonds, and the performance of the covenants therein and in the Indenture contained, the Company by these presents does grant,

bargain, convey, assign, transfer, mortgage, pledge, set over and confirm to the Trustee, In Trust, With Power Of Sale, all of the real property located in the County of Bernalillo, State of New Mexico, and more particularly described on Exhibit "1" to this Third Amendment as if set forth in this grant in full, together with all buildings, structures, improvements and other appurtenances situated thereon or therein.

(b)

Exhibit "A" to the Existing Indenture is hereby amended to add thereto those certain real properties described on Exhibit "1" to this Third Amendment.

3.     ORIGINAL ISSUANCE OF SERIES C BONDS.

        There is hereby added to the Existing Indenture a new Article, to be entitled Article XVII and which shall read in its entirety as follows:

"ARTICLE XVII
TERMS AND ISSUE OF SERIES C BONDS

         Section 17.01.    Specific Title, Terms and Forms.     There shall be a third series of Bonds entitled "First Mortgage Bonds, Series C 6.10%, due December 1, 2024" (herein called the "Series C Bonds" ). The form thereof shall be substantially as set forth in Article II with such insertions, omissions, substitutions and variations as may be determined by the officers executing the same as evidenced by their execution thereof to reflect the applicable terms of the Series C Bonds established by this Article. The precise form of the Series C Bonds shall be as set forth in Exhibit A to the separate Bond Purchase Agreements (the "Purchase Agreement" ) dated as of December 15, 2004 between the Company, Southwest Water Company and each Purchaser named therein pursuant to which the Series C Bonds are sold and the Trustee is authorized to refer to such Purchase Agreement when any Series C Bonds are presented to the Trustee for authentication.

        The Stated Maturity of the Series C Bonds shall be December 1, 2024, and the aggregate principal amount thereof which may be authenticated and delivered and Outstanding is limited to $12,000,000.

        The Series C Bonds may be issued only as registered Bonds in denominations of $1,000 and any multiple thereof. The Series C Bonds shall bear interest from the later of the initial issuance of the Series C Bonds or the most recent Interest Payment Date to which interest has been paid or duly provided for. The Series C Bonds shall bear interest payable semi-annually on June 1 and December 1 of each year (the Interest Payment Dates of the Series C Bonds), at the rate of 6.10% per annum until the principal thereof shall be paid or duly provided for; provided that interest on any overdue principal, overdue Redemption Price, and (to the extent permitted by applicable law) overdue interest, shall accrue at a rate equal to the lesser of (a) the highest rate allowed by applicable law or (b) 7.10% per annum. Interest shall be computed on the basis of a 360 day year of twelve 30 day months. In no event shall the interest payable on any Series C Bonds (including any interest on overdue interest or any overdue Redemption Price) exceed the maximum amount which the Holder thereof may legally collect under the then applicable usury law. In the event that it is hereafter determined by a court of competent jurisdiction that the interest payable under any Series C Bond (including any interest on any overdue Redemption Price or overdue interest) is in excess of the amount which the Holder thereof may legally collect under the then applicable usury law, then (i) all interest actually paid (including any interest on overdue interest or any overdue Redemption Price) in excess of the maximum amount legally collectible by such Holder shall be applied to the payment of principal of such Series C Bond or, if all principal shall previously have been paid, promptly repaid by such Holder to the Company, and (ii) interest on such Series C Bond (including any interest on overdue interest or any overdue Redemption Price) subsequent to the date of such determination shall be reduced to the maximum amount which it is determined that the Holder may collect under the then applicable usury law.

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        Notwithstanding the provisions of Section 5.05 [Deposit of Redemption Price] or other provisions in the Indenture to the contrary, the principal and the Redemption Price of, and the interest on, the Series C Bonds shall be payable by depositing such amounts, before 12:00 noon, New York time, by federal funds bank wire transfer, in the account of each Bondholder of the Series C Bonds in any bank in the United States as may be designated in a written notice to the Company by such Bondholder, or in such other manner as may be directed, or to such other address in the United States as may be designated, in writing by such Bondholder. The addresses on Annex 1 to the Purchase Agreement with respect to the initial purchasers of the Series C Bonds shall be deemed to constitute notice, direction or designation (as appropriate) to the Company with respect to direct payments to such purchasers as aforesaid. With regard to any Series C Bond, the bank designated pursuant to this paragraph with respect to such Series C Bond shall be the Place of Payment in respect of such Series C Bond.

        The Regular Record Date referred to in Section 2.10 [Payment of Interest on Bonds; Interest Rights Preserved] for the payment of the interest payable on the Series C Bonds, and punctually paid or duly provided for, on any Interest Payment Date shall be the 15th day (whether or not a Business Day) of the calendar month next preceding such Interest Payment Date.

        If any payment due on, or with respect to, any Series C Bonds shall fall due on a day other than a Business Day, then such payment shall be made on the first Business Day following the day on which such payment shall have so fallen due; provided that if all or any portion of such payment shall consist of a payment of interest, for purposes of calculating such interest, such payment shall not be deemed to have been originally due on such first following Business Day, and such interest shall accrue and be payable only to the Interest Payment Date.

         Section 17.02.    Exchangeability.     Subject to Section 2.08 [Registration, Transfer and Exchange], all Series C Bonds shall be fully interchangeable, and, upon surrender at the office or agency of the Company which the Company maintains pursuant to Section 6.02 [Maintenance of Office or Agency] and delivery by the Company to the Bond Registrar, shall be exchangeable for other Series C Bonds of a different authorized denomination or denominations, as requested by the Holder surrendering the same. The Company will execute, and the Trustee shall authenticate and deliver, Series C Bonds whenever the same are required for any such exchange.

         Section 17.03.    Redemption.     

        A.    The Series C Bonds are subject to redemption, in whole or in part, before their Stated Maturity in the following events and in the manner provided in Article V [Redemption of Bonds]:

(1)

At any time after issuance, at the option of the Company evidenced by a Board Resolution, in an amount not less than 5% of the aggregate principal amount of the Series C Bonds Outstanding in the case of a partial redemption, at a Redemption Price equal to 100% of the principal amount of the Series C Bonds to be redeemed, together with the Make-Whole Amount at such time (as shall be calculated by the Company which calculations shall be set forth in an Officers' Certificate delivered to each Holder of Series C Bonds and to the Trustee two (2) Business Days prior to the date of Redemption) and interest accrued to the Redemption Date, on a Redemption Date specified by the Company in compliance with Section 5.02 [Election to Redeem; Notice to Trustee]; and

(2)

From Major Event Proceeds, at a Redemption Price equal to 100% of the principal amount of Bonds to be redeemed, together with interest accrued to the Redemption Date, and on a Redemption Date that is the first date for which notice of redemption can be given by the Trustee as provided in Article V [Redemption of Bonds]; provided that such redemption may only be made if the Series C Bonds are redeemed pro rata with all other Outstanding Bonds of whatever series.

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        B.    Notwithstanding the last sentence of the first paragraph of Section 5.04 [Notice of Redemption] and the first sentence of the second paragraph of Section 1.04 [Notices to Bondholders; Waiver], the giving of notice of redemption to each Holder of a Series C Bond, as provided in Section 5.04, shall be a condition precedent to the Company's right to redeem Series C Bonds in accordance with the foregoing clauses A(1) and A(2) of this Section 17.03. Any notice of redemption to any Holder of Series C Bonds for a redemption pursuant to clause A(1) of this Section 17.03 shall be accompanied by an Officers' Certificate as to the estimated Make-Whole Amount due in connection with such redemption (calculated as if the date of such notice were the date of such redemption) setting forth the details of such computation.

        C.    Notwithstanding the provisions of Section 5.03 [Selection by Trustee of Bonds to Be Redeemed], if there is more than one Holder of the Series C Bonds, the aggregate principal amount of each required or optional partial redemption of the Series C Bonds shall be allocated in units of $1,000 or multiples thereof among the Holders of the Series C Bonds at the time Outstanding in proportion, as nearly as practicable, to the respective unpaid principal amounts of the Series C Bonds then Outstanding held by each such Holder of Series C Bonds, with adjustments, to the extent practicable, to equalize for any prior redemptions not in such proportion.

        D.    Notwithstanding the second sentence of Section 5.06 [Bonds Payable on Redemption Date] or the provisions of Section 5.07 [Bonds Redeemed in Part], no Holder of any Series C Bonds shall be required to surrender such Bond to any Person, or to file, or cause to be filed, with the Trustee any agreement or certificate required by Section 5.07, prior to receiving any payment thereon or in respect thereof; provided, however, that upon payment of the principal or the Redemption Price in full, and interest on and all other amounts in respect of such Series C Bond, the Holder thereof shall promptly thereafter surrender such Series C Bond to the Company and the Company shall deliver such redeemed Bonds to the Bond Registrar for cancellation. Any such Series C Bond so surrendered shall be cancelled and shall not be reissued, and no new Series C Bond shall be issued in lieu of such surrendered Series C Bond.

        E.    The Series C Bonds may be redeemed from Trust Moneys, as provided in Section 8.04 [Retirement of Bonds], including from moneys received by the Trustee as a result of casualty or condemnation, as provided in Articles VII [Possession and Release of Property] and VIII [Application of Trust Moneys], but only at the time, in the manner and at the Redemption Price specified in clauses (A)(1) and (2) of this Section 17.03. If the Series C Bonds shall be redeemed under Section 17.03A(2), then said Series C Bonds shall be redeemed pro rata with the Series B Bonds and any other Bonds having the benefit of a redemption provision substantially identical to that contained in Section 17.03A(2), in proportion, as nearly as practicable, to the respective unpaid principal amounts of all such Bonds Outstanding on the Redemption Date.

         Section 17.04.    Payment of Optional Redemption Price.     If the giving of notice of optional redemption shall have been completed as required in Article V [Redemption of Bonds], the Series C Bonds or portions of such Series C Bonds specified in such notice shall become due and payable on the Redemption Date at the applicable Redemption Price set forth in Section 17.03. On and after the Redemption Date (unless the Company shall default in the payment of such Bonds on the Redemption Date) interest on the Series C Bonds or the portions of the Series C Bonds so called for redemption shall cease to accrue.

        If any Holder of any Series C Bond which is redeemed in part only shall present such Bond to the Company, the Company shall execute and the Trustee shall authenticate and deliver to such Holder, at the expense of the Company, a new Series C Bond or Bonds in aggregate principal amount equal to the unredeemed portion of the Series C Bond so presented.

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         Section 17.05.    Authentication and Delivery.     Upon the execution and delivery of this Third Amendment, the Company shall execute and deliver to the Trustee, and the Trustee shall authenticate, the Series C Bonds and deliver them to the purchasers thereof as instructed by the Company.

        Prior to the delivery by the Trustee of the Series C Bonds there shall be filed with the Trustee original executed counterparts of this Third Amendment, the Purchase Agreement, the Title Policies or commitments for issuance thereof, evidence of recording of this Third Amendment in the land records of Bernalillo County, New Mexico and all other documents required by the Indenture as a condition to the issuance of the Series C Bonds."

         Section 17.06.    Consent of Holders of Series C Bond to Supplemental Indentures under Section 13.02.    
Supplemental Indentures referred to in the first sentence of Section 13.02 [Supplemental Indentures with Consent of Bondholders] which affect the Holders of the Series C Bonds shall require the consent of the Holders of not less than 70% in principal amount of the Series C Bonds then outstanding.

4.     CERTAIN AMENDMENTS TO ARTICLE I.

        (a)      Make-Whole Amount Definitions.     Section 1.01 [Definitions] of the Existing Indenture is hereby amended by adding the following definition of Make-Whole Amount for the Series C Bonds and the following related definitions:

         "Make-Whole Amount" means, with respect to any Series C Bond, an amount equal to the excess, if any, of the Discounted Value of the Remaining Scheduled Payments with respect to the Called Principal of such Bond over the amount of such Called Principal, provided that the Make-Whole Amount may in no event be less than zero. For the purposes of determining the Make-Whole Amount, the following terms have the following meanings:

         "Called Principal" means, with respect to any Series C Bond, the principal of such Bond that is to be redeemed pursuant to Section 17.03 [Redemption] or has become or is declared to be immediately due and payable pursuant to Section 9.02 [Acceleration of Maturity; Recission and Annulment], as the context requires.

         "Discounted Value" means, with respect to the Called Principal of any Series C Bond, the amount obtained by discounting all Remaining Scheduled Payments with respect to such Called Principal from their respective scheduled due dates to the Settlement Date with respect to such Called Principal, in accordance with accepted financial practice and at a discount factor (applied on the same periodic basis as that on which interest on the Series C Bonds is payable) equal to the Reinvestment Yield with respect to such Called Principal.

         "Reinvestment Yield" means, with respect to the Called Principal of any Series C Bond, .50% plus the yield to maturity implied by (i) the yields reported, as of 10:00 A.M. (New York City time) on the second Business Day preceding the Settlement Date with respect to such Called Principal, on the display page of the Bloomberg Financial Markets Services Screen PX1 or the equivalent screen provided by Bloomberg Financial Markets Commodities News for actively traded U.S. Treasury Securities having a maturity equal to the Remaining Life of such Called Principal as of such Settlement Date, or (ii) if such yields are not reported as of such time or the yields reported as of such time are not ascertainable, the Treasury Constant Maturity Series Yields reported, for the latest day for which such yields have been so reported as of the second Business Day preceding the Settlement Date with respect to such Called Principal, in Federal Reserve Statistical Release H.15 (519) (or any comparable successor publication) for actively traded U.S. Treasury securities having a constant maturity equal to the Remaining Life of such Called Principal as of such Settlement Date. Such implied yield will be determined, if necessary, by (a) converting U.S. Treasury bill quotations to bond-equivalent yields in accordance with accepted financial practice

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and (b) interpolating linearly between (1) the actively traded U.S. Treasury security with the maturity closest to and greater than the Remaining Life and (2) the actively traded U.S. Treasury security with the maturity closest to and less than the Remaining Life.

         "Remaining Life" means, with respect to any Called Principal, the number of years (calculated to the nearest one-twelfth year) from the Settlement Date to the maturity of the Series C Bonds.

         "Remaining Scheduled Payments" means, with respect to the Called Principal of any Series C Bond, all payments of such Called Principal and interest thereon that would be due after the Settlement Date with respect to such Called Principal if no payment of such Called Principal were made prior to its scheduled due date, provided that if such Settlement Date is not a date on which interest payments are due to be made under the terms of the Series C Bonds, then the amount of the next succeeding scheduled interest payment will be reduced by the amount of interest accrued to such Settlement Date and required to be paid on such Settlement Date pursuant to this provision.

         "Settlement Date" means, with respect to the Called Principal of any Series C Bond, the date on which such Called Principal is to be redeemed pursuant to Section 17.03 [Redemption] or Section 9.02 [Acceleration of Maturity; Recission and Annulment], as the context requires.

        (b)      Definition of Officers' Certificate.     The definition of "Officers' Certificate" contained in Section 1.01 [Definitions] of the Existing Indenture is hereby amended to read in its entirety as follows:

        " Officers' Certificate" means a certificate signed by (a) either the Chairman of the Board, the President or a Vice President and (b) by either the Treasurer or the Secretary or an Assistant Secretary of the Company, and delivered to the Trustee. Wherever this Indenture requires that an Officers' Certificate must be signed also by an Engineer or an Accountant or other expert, such Engineer, Accountant or other expert may (except as otherwise expressly provided in this Indenture) be in the employ of the Company and shall be acceptable to the Trustee."

        (c)      Definition of Place of Payment.     The definition of "Place of Payment" contained in Section 1.01 [Definitions] of the Existing Indenture is hereby amended to read, in its entirety, as follows:

         "Place of Payment" means, (a) when used with respect to the Series B Bonds (except as provided in clause (c) below), the place for payment of the principal, Make-Whole Amount, if any, and interest upon the Series B Bonds designated in Section 16.01; (b) when used with respect to the Series C Bonds (except as provided in clause (c) below), the place for payment of the principal, Make-Whole Amount, if any, and interest upon the Series C Bonds designated in Section 17.01; and (c) with respect to any exchange of Series B Bonds pursuant to Section 16.02 [Exchangeability], with respect to any exchange or surrender for redemption of any Series C Bonds pursuant to Section 17.02 [Exchangeability] and with respect to Bonds of any other series means a city or any political subdivision thereof in which the Company is by this Indenture required to maintain an office or agency pursuant to Section 6.02 [Maintenance of Office or Agency].

        (d)      Definition of Prior Lien .    The second line of the definition of "Prior Lien" contained in Section 1.01 [Definitions] of the Existing Indenture is hereby amended by adding the word "to" after the words "Exhibit A".

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        (e)      Section 1.03     Notices.    Section 1.03 [Notices Etc. to Trustee and Company] is amended to restate the first address set forth in Section 1.03B to read as follows:

        (f)      Section 1.13.     Section 1.13 [Deed of Trust Act Notices] of the Existing Indenture is hereby restated in its entirety to read as follows:

        " Section 1.13. Deed of Trust Act Notices. For the purpose of complying with Section 48-10-5C of the Deed of Trust Act, the addresses for notices pursuant to the Deed of Trust Act of the Trustee, the trustor ( i.e., the Company) and each beneficiary ( i.e., each holder of Bonds issued and outstanding pursuant to this Indenture) shall be as follows:

        Service of such notices pursuant to the Deed of Trust Act shall be in accordance with the provisions thereof."

5.     AMENDMENTS TO ARTICLE II.

        (a)      Section 2.01.     Section 2.01 [General Limitations; Issuable in Series] of the Existing Indenture is hereby restated in its entirety to read as follows:

         "Section 2.01. General Limitations; Issuable in Series. The aggregate principal amount of Bonds which may be authenticated and delivered and Outstanding under this Indenture is not limited, except as provided in Articles III [Terms and Issue of Series A Bonds] and IV [Authentication and Delivery o