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THIS INSTRUMENT, WHEN
RECORDED, SHOULD BE
RETURNED TO:

Orrick, Herrington &
   Sutcliffe LLP
3050 K Street, NW
Washington, D.C.  20007
Attn: Kyle W. Drefke, Esq.

                                                                EXHIBIT 10(a)(2)

================================================================================


                          FIRST SUPPLEMENTAL INDENTURE

                            DATED AS OF APRIL 9, 2003

                                       OF

                                  AQUILA, INC.

                                       TO

                          BANK ONE TRUST COMPANY, N.A.,
                                     TRUSTEE


                               -------------------

                               SUPPLEMENTAL TO THE
                     INDENTURE OF MORTGAGE AND DEED OF TRUST
                            DATED AS OF APRIL 1, 2003

                               -------------------

================================================================================

                                               INDENTURE OF MORTGAGE AND DEED OF
                                               TRUST, DATED AS OF APRIL 1, 2003
                                               RECORDED APRIL ___, 2003:
                                               BOOK _______,
                                               PAGE _______,
                                               ____________ COUNTY ___________.

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          This FIRST SUPPLEMENTAL INDENTURE, dated as of April 9, 2003, between
AQUILA, INC., a corporation organized and existing under the laws of the State
of Delaware (the "COMPANY"), having its principal office at 20 West Ninth
Street, Kansas City, Missouri 64105, and BANK ONE TRUST COMPANY, N.A., a
national banking association, as trustee (the "TRUSTEE"), having a corporate
trust office at One Bank Plaza, Suite IL 1-0823, Chicago, Illinois 60670-0823.

                             RECITALS OF THE COMPANY

          WHEREAS, the Company has heretofore executed and delivered to the
Trustee an Indenture of Mortgage and Deed of Trust, dated as of April 1, 2003
(the "INDENTURE"), providing for the issuance by the Company from time to time
of its bonds, notes or other evidences of indebtedness (the "SECURITIES"), and
to provide security for the payment of the principal of and premium, if any, and
interest, if any, on the Securities; and

          WHEREAS, the Company, in the exercise of the power and authority
conferred upon and reserved to it under the provisions of the Indenture and
pursuant to appropriate resolutions of the Board of Directors, has duly
determined to make, execute and deliver to the Trustee this First Supplemental
Indenture to the Indenture as permitted by Sections 2.01, 3.01 and 13.01 of the
Indenture in order (i) to establish the form and terms of, and to provide for
the creation and issuance of, the initial series of Securities under the
Indenture in an initial aggregate principal amount of $430,000,000 (the "INITIAL
SERIES"), and (ii) to amend certain provisions of the Indenture pursuant to
Section 13.01 thereof; and

          WHEREAS, all acts necessary have been done to make the Initial Series
the valid, binding and legal obligations of the Company and to make this First
Supplemental Indenture a valid, binding and legal agreement of the Company when
executed by the Company and authenticated and delivered by the Trustee or any
Authenticating Agent and issued upon the terms and subject to the conditions
hereinafter and in the Indenture set forth.

          NOW, THEREFORE, THIS FIRST SUPPLEMENTAL INDENTURE WITNESSETH that, in
order (i) to establish the form and terms of, and to provide for the creation
and issuance of, the Initial Series, and (ii) to amend certain provisions of the
Indenture pursuant to Section 13.01 thereof, and for and in consideration of the
premises and of the covenants contained in the Indenture and in this First
Supplemental Indenture and for other good and valuable consideration the receipt
and sufficiency of which are hereby acknowledged, it is mutually covenanted and
agreed as follows:

                                    ARTICLE I

             DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

     SECTION 1.01.  DEFINITIONS. Each  capitalized  term that is used  herein
and is defined in the Indenture shall have the meaning specified in the
Indenture unless such term is otherwise defined herein.

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                                   ARTICLE II

                       TITLE, FORM AND TERMS OF THE BONDS

     SECTION 2.01.  TITLE OF THE BONDS. This First Supplemental Indenture hereby
creates the Initial Series designated as the "2003 Series A Bonds due May 15,
2006" of the Company (collectively, referred to herein as the "BONDS"). Pursuant
to the Indenture (which secures repayment of the Bonds), the Bonds shall
constitute a single series of Securities and may be issued in an aggregate
principal amount not to exceed $430,000,000 unless all Holders of the Bonds
consent to increase the aggregate principal amount of the Initial Series.

     SECTION 2.02.  FORM AND TERMS OF THE BONDS. The form and terms of the Bonds
will be set forth in an Officer's Certificate (attached hereto as Exhibit A)
delivered concurrently with the execution of this First Supplemental Indenture
by the Company to the Trustee pursuant to the authority granted by this First
Supplemental Indenture in accordance with Sections 2.01 and 3.01 of the
Indenture.

                                   ARTICLE III

     SECTION 3.01.  Pursuant to Section 13.01 of the Indenture, so long as any
Bonds of the Initial Series shall be Outstanding, the Indenture shall be amended
as follows:

     (a)  DEFINITIONS. Section 1.01 of the Indenture is amended to include the
following additional definition in alphabetical order:

          "CREDIT AGREEMENT" means the Credit Agreement, dated as of April 9,
     2003, between the Company, the Lenders parties thereto from time to time,
     the Issuing Banks parties thereto from time to time, and Credit Suisse
     First Boston, acting through its Cayman Islands Branch, as Administrative
     Agent, Lead Arranger and Sole Book Runner."

     (b)  ISSUANCE OF SECURITIES.  Article IV of the Indenture is amended as
follows:

          (i)       Section 4.02(a) of the Indenture is amended by deleting the
text thereof in its entirety and inserting in lieu thereof the following:

          "Securities of any one or more series may be authenticated and
          delivered on the basis of Property Additions which do not constitute
          Funded Property in a principal amount not exceeding (i) seventy
          percent (70%) of the balance of the Cost or the Fair Value to the
          Company of such Property Additions constituting capital expenditures
          (whichever shall be less), and/or (ii) sixty percent (60%) of the Fair
          Value to the Company of any other Property Additions, after making any
          deductions and any additions pursuant to Section 1.03(b) except as
          otherwise specified in clause (b) of this Section 4.02."

                                       -2-
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          (ii)      Section 4.02(b)(ii)(A) of the Indenture is amended by
deleting the text thereof in its entirety and inserting in lieu thereof the
following:

          "describing generally all property constituting Property Additions and
          designated by the Company, in its discretion, to be made the basis of
          the authentication and delivery of such Securities (such description
          of property to be made by reference, at the election of the Company,
          either to specified items, units or elements of property or portions
          thereof, on a percentage or Dollar basis, or to properties reflected
          in specified accounts or subaccounts in the Company's books of account
          or portions thereof, on a Dollar basis), and stating the Cost of such
          portion of the property constituting capital expenditures and the Fair
          Value to the Company of such portion of such property not constituting
          capital expenditures;"

          (iii)     Section 4.02(b)(ii)(D) of the Indenture is amended by
deleting the text thereof in its entirety and inserting in lieu thereof the
following:

          "stating that such Property Additions, to the extent of (1) the Cost
          or Fair Value to the Company thereof (whichever is less) in the case
          of Property Additions constituting capital expenditures, or (2) the
          Fair Value to the Company, in the case of Property Additions not
          constituting capital expenditures, to be made the basis of the
          authentication and delivery of such Securities, do not constitute
          Funded Property;"

          (iv)      Section 4.02(b)(ii)(K) of the Indenture is amended by
inserting the text "constituting capital expenditures" immediately following the
text "Property Additions";

          (v)       Section 4.02(b)(ii)(M) of the Indenture is amended by
deleting the text thereof in its entirety and inserting in lieu thereof the
following:

          "stating the amount equal to sixty percent (60%) of the Fair Value to
          the Company of such Property Additions not constituting capital
          expenditures;"

          (vi)      Section 4.02(b)(ii) of the Indenture is amended to include
the following as new subsection (N) thereof:

          "(N)      stating the aggregate principal amount of the Securities to
                    be authenticated and delivered on the basis of (1) such
                    Property Additions constituting capital expenditures (such
                    amount not to exceed the amount stated pursuant to clause
                    (L) above), and (2) such Property Additions not constituting
                    capital expenditures (such amount not to exceed the amount
                    stated pursuant to clause (M) above);"

     (c)  COVENANTS. Article VI of the Indenture is amended by adding a new
Section 6.11 as follows:

          "SECTION 6.11. NOTICES. (a) The Company promptly will furnish to the
     Administrative Agent (as defined in the Credit Agreement) copies of all
     written notices

                                       -3-
<Page>

     received by or delivered to the Company from the Trustee or any other
     Person in connection with the Indenture.

          (b)       The Company shall provide the Administrative Agent (as
     defined in the Credit Agreement) with not less than five (5) Business Days'
     prior written notice (in accordance with Section 9.2 of the Credit
     Agreement) of any Company Request or Company Order for the issuance of
     additional Securities pursuant to Article IV, the release of any Mortgaged
     Property pursuant to Article VII, or the entering into of any supplemental
     indenture to this Indenture pursuant to Article XIII or any other action to
     be taken by the Trustee under the Indenture. The Trustee may not act upon
     any such Company Request or Company Order which does not include a
     certification that the Company has provided the notice required by this
     Section 6.11(b) to the Administrative Agent at least five (5) Business Days
     prior to the date of delivery of such Company Request or Company Order to
     the Trustee."

     (d)  MANDATORY PREPAYMENT UNDER THE CREDIT AGREEMENT. Section 7.08 of the
Indenture is amended to include the following as new clause (g) thereof:

          "(g)      Notwithstanding anything herein to the contrary, the Company
     may obtain the release of any part of the Mortgaged Property, or any
     interest therein, and the Trustee shall release all of its right, title and
     interest in and to the same from the Lien hereof, upon receipt by the
     Trustee of (a) a Company Request requesting the release of such property
     and transmitting therewith a form of instrument to effect such release, (b)
     an Opinion of Counsel to the effect that release of such property complies
     with the provisions of Section 6.7(d) of the Credit Agreement, and (c) an
     Officer's Certificate stating (i) that such Mortgaged Property will be
     transferred in a Disposition (as defined in the Credit Agreement) pursuant
     to Section 6.7(d) of the Credit Agreement, (ii) that the proceeds thereof
     will be applied pursuant to Section 2.7(b)(i) of the Credit Agreement, and
     (iii) that no Event of Default has occurred and is continuing, subject to
     the right of the Company pursuant thereto to retain the first Ten Million
     Dollars ($10,000,000) of the Net Cash Proceeds (as defined in the Credit
     Agreement) thereof."

     (e)  EVENTS OF DEFAULT. Section 9.01 is amended to delete the period at the
end of clause (f) thereof, insert "; or" in lieu thereof and to include the
following as a new clause (g) thereof:

     "(g) the occurrence and continuance of any Event of Default as defined in
          the Credit Agreement."

For the avoidance of doubt, when the Bonds cease to be Outstanding, the
amendments to the Indenture effected pursuant to this Article III shall cease to
be in effect.

                                   ARTICLE IV

                            MISCELLANEOUS PROVISIONS

     SECTION 4.01.  TRUSTEE MATTERS. The Trustee makes no undertaking or
representations in respect of, and shall not be responsible in any manner
whatsoever for and in respect of, the

                                       -4-
<Page>

validity or sufficiency of this First Supplemental Indenture or the proper
authorization or the due execution hereof by the Company or for or in respect of
the recitals and statements contained herein, all of which recitals and
statements are made solely by the Company.

     SECTION 4.02.  EFFECT ON INDENTURE. Except as expressly amended and
supplemented hereby, the Indenture shall continue in full force and effect in
accordance with the provisions thereof and the Indenture is in all respects
hereby ratified and confirmed. This First Supplemental Indenture shall be
construed as an indenture supplemental and amendatory to the Indenture and all
of its provisions shall be deemed a part of the Indenture in the manner and to
the extent herein and therein provided. Except to the extent otherwise provided
herein, all of the provisions, terms, covenants and conditions of the Indenture
shall be applicable to the Bonds to the same extent as if set forth herein.

     SECTION 4.03.  GOVERNING LAW. This First Supplemental Indenture shall be
governed by and construed in accordance with the law of the State of New York
(including without limitation Section 5-1401 of the New York General Obligations
Law or any successor to such statute), except to the extent that the Trust
Indenture Act shall be applicable and except to the extent that the law of any
jurisdiction wherein any portion of the Mortgaged Property is located shall
mandatorily govern the creation of a mortgage lien on and security interest in,
or perfection, priority or enforcement of the Lien of the Indenture or exercise
of remedies with respect to, such portion of the Mortgaged Property.

     SECTION 4.04.  EFFECTIVE DATE. Although this First Supplemental Indenture
is dated for convenience and for the purpose of reference as of April 9, 2003,
this First Supplemental Indenture shall become effective upon the execution and
delivery by the Company and the Trustee.

     SECTION 4.05.  COUNTERPARTS. This First Supplemental Indenture may be
executed in any number of counterparts, each of which when so executed shall be
deemed to be an original, but all such counterparts shall together constitute
but one and the same instrument.

                        [SIGNATURES FOLLOW ON NEXT PAGE]

                                       -5-
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     IN WITNESS WHEREOF, the parties hereto have caused this First Supplemental
Indenture to be duly executed as of the day and year first written above.

                                AQUILA, INC.


                                By:     /s/ Randal P. Miller
                                      ------------------------------------
                                Name:  Randal P. Miller
                                Title: Vice President - Finance and Treasurer


                                BANK ONE TRUST COMPANY, N.A., as Trustee


                                By:         /s/ J. Morand
                                    ------------------------------
                                Name:  J. Morand
                                Title: Vice President

<Page>

STATE OF MISSOURI      )
                       )  SS.
COUNTY OF JACKSON      )


     On this 9th day of April, 2003, before me appeared Randal P. Miller to me
personally known, who, being by me duly sworn, did say that he is the Vice
President - Finance and Treasurer of Aquila, Inc., a corporation described in
and which executed the foregoing instrument, and that said instrument was signed
on behalf of said corporation by authority of its board of directors, and said
Randal P. Miller acknowledged said instrument to be the free act and deed of
said corporation.

[NOTARIAL SEAL]                                       /s/ Sara L. Henning
                                                    -----------------------
                                                         Notary Public

My Commission Expires:

     12/28/2005
----------------------

STATE OF ILLINOIS      )
                       )  SS.
COUNTY OF COOK         )


     On this 9th day of April, 2003, before me appeared J. Morand to me
personally known, who, being by me duly sworn, did say that he is the Vice
President of Bank One Trust Company, N.A., a national banking association
described in and which executed the foregoing instrument, and that said
instrument was signed on behalf of said national banking association by
authority of its board of directors, and said J. Morand acknowledged said
instrument to be the free act and deed of said national banking association.

[NOTARIAL SEAL]                                      /s/ Darla R. Coulson
                                                    -----------------------
                                                         Notary Public

My Commission Expires:

     02/27/2007
----------------------