****


****


****


**EXHIBIT
4.1**











EXECUTION
COPY











**MIDAMERICAN
ENERGY COMPANY**





and





**THE
BANK OF NEW YORK,**





as
Trustee





________________


4.650%
Notes due 2014





________________


Third
Supplemental Indenture





________________





Dated as
of October 1, 2004



















THIRD
SUPPLEMENTAL INDENTURE, dated as of October 1, 2004 (herein called the
" Third
Supplemental Indenture "),
between MIDAMERICAN ENERGY COMPANY, a corporation duly organized and existing
under the laws of the State of Iowa (herein called the " Company "), and
THE BANK OF NEW YORK, a New York banking association duly organized and existing
under the laws of the United States of America, as Trustee (herein called the
" Trustee "), under
the Original Indenture referred to below.





W I T N E
S S E T H :





WHEREAS,
the Company has heretofore executed and delivered to the Trustee an indenture
dated as of February 8, 2002, as amended (herein called the " Original
Indenture "), as
supplemented by the First Supplemental Indenture dated as of February 8, 2002
and the Second Supplemental Indenture dated as of January 14, 2003, to provide
for the issuance from time to time of its unsubordinated debentures, notes or
other evidences of indebtedness, the form and terms of which are to be
established as set forth in Sections 2.01 and 3.01 of the Original
Indenture;





WHEREAS,
Section 9.01 of the Original Indenture provides, among other things, that the
Company and the Trustee may enter into indentures supplemental to the Original
Indenture for, among other things, (i) the purpose of establishing the form and
terms of the Securities (as defined in the Original Indenture) of any series as
permitted by Sections 2.01 and 3.01 of the Original Indenture, and (ii) to add
to the covenants of the Company for the benefit of the Holders of all or any
series of Securities (as defined in the Original Indenture);





WHEREAS,
the Company desires to create one series of securities to be designated the
"4.650% Notes due 2014" and all action on the part of the Company necessary to
authorize the issuance of up to three hundred fifty million dollars
($350,000,000) aggregate principal amount of such securities (the " Securities ") under
the Original Indenture and this Third Supplemental Indenture has been duly
taken;





WHEREAS,
the Company and the Trustee desire to make certain amendments to the Original
Indenture in conformance with the requirements described above; and





WHEREAS,
all acts and things necessary to make the Securities, when executed by the
Company and authenticated and delivered by the Trustee as provided in the
Original Indenture, the valid and binding obligations of the Company and to
constitute these presents a valid and binding supplemental indenture and
agreement according to its terms, have been done and performed.






1





NOW,
THEREFORE, THIS THIRD SUPPLEMENTAL INDENTURE WITNESSETH:





That in
consideration of the premises and of the acceptance and purchase of the
Securities by the holders thereof and of the acceptance of this trust by the
Trustee, the Company covenants and agrees with the Trustee, for the equal
benefit of holders of the Securities, as follows:





ARTICLE
I


DEFINITIONS





Unless
otherwise defined herein, the use of the terms and expressions herein is in
accordance with the definitions, uses and constructions contained in the
Original Indenture and the form of Security attached hereto as Exhibit
A .





ARTICLE
II


TERMS AND
ISSUANCE OF THE SECURITIES





Section
2.01. Issue of Securities. One series of notes, which shall be designated the
"4.650% Notes due 2014", shall be executed, authenticated and delivered in
accordance with the provisions of, and shall in all respects be subject to, the
terms, conditions and covenants of the Original Indenture and this Third
Supplemental Indenture (including the form of Security set forth in Exhibit
A ).





Section
2.02. Optional Redemption. The Securities may be redeemed, in whole or in part,
at the option of the Company pursuant to the terms set forth in Annex
1 to the
Securities to be redeemed. The provisions of Article XI of the Original
Indenture shall also apply to any optional redemption of Securities by the
Company.





Section
2.03. Defeasance and Discharge. The provisions of Section 14.02 of the Original
Indenture shall be applicable to the Securities.





Section
2.04. Covenant Defeasance. The provisions of Section 14.03 of the Original
Indenture shall be applicable to the Securities.





Section
2.05. Place of Payment. The Place of Payment in respect of the Securities will
be in The City of New York, initially at the Corporate Trust Office of The Bank
of New York (which as of the date hereof is located at 101 Barclay Street, 8
West, New York, New York 10286, Attention: Corporate Trust
Administration).





Section
2.06. Form of Securities; Incorporation of Terms. The form of the Securities
shall be substantially in the form of Exhibit
A , the
terms of which are herein incorporated by reference and which are part of this
Third Supplemental Indenture. The Securities shall be issued as one or more
Global Securities in fully registered form, as determined in accordance with
Section 2.01 of the Original Indenture. The Global Securities shall be delivered
by the Trustee to the Depositary, as the Holder thereof, or a nominee or
custodian therefore, to be held by the Depositary in accordance with the
Original Indenture.




2








Section
2.07. Exchange of the Global Securities. Each of the Global Securities shall be
exchangeable for definitive Securities only as provided in Section 3.05 of the
Original Indenture.





Section
2.08. Regular Record Date for the Securities. The Regular Record Date for the
Securities shall be the March 15 or September 15 immediately prior to each
Interest Payment Date.





Section
2.09. Authorized Denominations. Beneficial interests in Global Securities, as
well as definitive Securities, may be held only in denominations of $1,000 and
integral multiples of $1,000 in excess thereof.





Section
2.10. Additional Securities. The Company may from time to time, without the
consent of the Holders of the Securities, create and issue further securities
having the same terms and conditions as the Securities in all respects, except
for the original issue date and offering price. Additional Securities issued in
this manner will be consolidated with, and form a single series with, the
Securities and shall thereafter be deemed Securities for all
purposes.





ARTICLE
III


DEPOSITARY





Section
3.01. Depositary. The Depositary Trust Company, its nominees and their
respective successors are hereby appointed Depositary with respect to the Global
Securities.





ARTICLE
IV


AMENDMENTS
TO ORIGINAL INDENTURE





Section
4.01. Amendments. The Original Indenture is hereby amended as
follows:





(a)  Section
1.01 of the Original Indenture is hereby amended to add or modify the following
definitions, as the case may be:








3








" 'Common
Shareholders Equity ' means,
at any time, the total shareholders' equity of the Company and its consolidated
subsidiaries, determined on a consolidated basis in accordance with generally
accepted accounting principles, as of the end of the most recently completed
fiscal quarter of the Company for which financial information is then
available."





"' Midwest
Power Indenture ' means
the General Mortgage Indenture and Deed of Trust, dated as of January 1, 1993,
between Midwest Power Systems Inc. and Morgan Guaranty Trust Company of New
York, trustee (Harris Trust and Savings Bank, successor trustee), and indentures
supplemental thereto."





"' Permitted
Encumbrances '
means:





(a)  (i) any
mortgage, pledge or other lien or encumbrance on any property hereafter acquired
or constructed by the Company or a Subsidiary, or on which property so
constructed is located, and created prior to, contemporaneously with or within
360 days after, such acquisition or construction or the commencement of
commercial operation of such property to secure or provide for the payment of
any part of the purchase or construction price of such property, or (ii) any
property subject to any mortgage, pledge, or other lien or encumbrance upon such
property existing at the time of acquisition thereof by the Company or any
Subsidiary, whether or not assumed by the Company or such Subsidiary, or (iii)
any mortgage, pledge or other lien or encumbrance existing on the property,
shares of stock, membership interests or indebtedness of a corporation or
limited liability company at the time such corporation or limited liability
company shall become a Subsidiary or any pledge of the shares of stock or
membership interests of such corporation or limited liability company prior to,
contemporaneously with or within 360 days after such corporation or limited
liability company shall become a Subsidiary to secure or provide for the payment
of any part of the purchase price of such stock or membership interests, or (iv)
any conditional sales agreement or other title retention agreement with respect
to any property hereafter acquired or constructed; provided that, in the case of
clauses (i) through (iv), the lien of any such mortgage, pledge or other lien
does not spread to property owned prior to such acquisition or construction or
to other property thereafter acquired or constructed other than additions to
such acquired or constructed property and other than property on which property
so constructed is located; and provided, further, that if a firm commitment from
a bank, insurance company or other lender or investor (not including the
Company, a Subsidiary or an Affiliate of the Company) for the financing of the
acquisition or construction of property is made prior to, contemporaneously with
or within the 360-day period hereinabove referred to, the applicable mortgage,
pledge, lien or encumbrance shall be deemed to be permitted by this clause (a)
whether or not created or assumed within such period;




4








(b)  any
mortgage, pledge or other lien or encumbrance created for the sole purpose of
extending, renewing or refunding any mortgage, pledge, lien or encumbrance
permitted by clause (a) of this definition; provided, however, that the
principal amount of indebtedness secured thereby shall not exceed the principal
amount of indebtedness so secured at the time of such extension, renewal or
refunding and that such extension, renewal or refunding mortgage, pledge, lien
or encumbrance shall be limited to all or any part of the same property that
secured the mortgage, pledge or other lien or encumbrance extended, renewed or
refunded;





(c)  liens for
taxes or assessments or governmental charges or levies not then due and
delinquent or the validity of which is being contested in good faith, and
against which an adequate reserve has been established; liens on any property
created in connection with pledges or deposits to secure public or statutory
obligations or to secure performance in connection with bids or contracts;
materialmen's, mechanics', carrier's, workmen's, repairmen's or other like
liens; or liens on any property created in connection with deposits to obtain
the release of such liens; liens on any property created in connection with
deposits to secure surety, stay, appeal or customs bonds; liens created by or
resulting from any litigation or legal proceeding which is currently being
contested in good faith by appropriate proceedings; leases and liens, rights of
reverter and other possessory rights of the lessor thereunder; zoning
restrictions, easements, rights-of-way or other restrictions on the use of real
property or minor irregularities in the title thereto; and any other liens and
encumbrances similar to those described in this clause (c), the existence of
which, in the opinion of the board of directors of the Company, does not
materially impair the use by the Company or a Subsidiary of the affected
property in the operation of the business of the Company or a Subsidiary, or the
value of such property for the purposes of such business;





(d)  any
mortgage, pledge or other lien or encumbrance created after October 1, 2004 on
any property leased to or purchased by the Company or a Subsidiary after that
date and securing, directly or indirectly, obligations issued by a State, a
territory or a possession of the United States, or any political subdivision of
any of the foregoing, or the District of Columbia, to finance the cost of
acquisition or cost of construction of such property; provided that the interest
paid on such obligations is entitled to be excluded from gross income of the
recipient pursuant to Section 103(a)(1) of the Internal Revenue Code of 1986, as
amended (or any successor to such provision), as in effect at the time of the
issuance of such obligations;




5








(e)  any
mortgage, pledge or other lien or encumbrance on any property now owned or
hereafter acquired or constructed by the Company or a Subsidiary, or on which
property so owned, acquired or constructed is located, to secure or provide for
the payment of any part of the construction price or cost of improvements of
such property, and created prior to, contemporaneously with or within 360 days
after, such construction or improvement; provided that if a firm commitment from
a bank, insurance company or other lender or investor (not including the
Company, a Subsidiary or an Affiliate of the Company) for the financing of the
acquisition or construction of property is made prior to, contemporaneously with
or within the 360-day period hereinabove referred to, the applicable mortgage,
pledge, lien or encumbrance shall be deemed to be permitted by this clause (e)
whether or not created or assumed within such period; and





(f)  any
mortgage, pledge or other lien or encumbrance not otherwise described in clauses
(a) through (e); provided that the aggregate amount of indebtedness secured by
all such mortgages, pledges, liens or encumbrances does not exceed the greater
of $100,000,000 or 10% of Common Shareholders' Equity."





"' Principal
Facility ' means
the real property, fixtures, machinery and equipment relating to any facility
owned by the Company or any Subsidiary, except any facility that is not of
material importance to the business conducted by the Company and its
Subsidiaries, taken as a whole."





"' Regulated
Subsidiary ' means
any Subsidiary which owns or operates facilities used for the generation,
transmission or distribution of electric energy and is subject to the
jurisdiction of any governmental authority of the United States or any state or
political subdivision thereof, as to any of its: rates; services; accounts;
issuances of securities; affiliate transactions; or construction, acquisition or
sale of any such facilities, except that any 'exempt wholesale generator', as
defined in 15 USC 79z-5a(a)(1), 'qualifying facility', as defined in 18 CFR
292.101(b)(1), 'foreign utility company', as defined in 15 USC 79z-5b(a)(3), and
'power marketer', as defined in NORTHWEST POWER MARKETING COMPANY, L.L.C., 75
FERC PARA 61,281, shall not be a Regulated Subsidiary."





"' Subsidiary ' means a
corporation or limited liability company more than 50% of the outstanding voting
stock or voting membership interests of which is or are owned, directly or
indirectly, by the Company or by one or more other Subsidiaries, or by the
Company and one or more other Subsidiaries. For the purposes of this definition,
(1) 'voting stock' means stock which ordinarily has voting power for the
election of directors, whether at all times or only so long as no senior class
of stock has such voting power by reason of any contingency, and (2) 'voting
membership interests' means membership interests which ordinarily have voting
power for the election of directors (or the equivalent thereof), whether at all
times or only so long as no senior class of membership interests have such
voting power by reason of any contingency."





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"' Wholly-Owned
Subsidiary ' means a
Subsidiary of which all of the outstanding voting stock or voting membership
interests (other than directors' qualifying shares) is or are at the time,
directly or indirectly, owned by the Company, or by one or more Wholly-Owned
Subsidiaries of the Company or by the Company and one or more Wholly-Owned
Subsidiaries."





(b)  Section
10.06 of the Original Indenture is hereby amended by replacing the reference to
Section 10.04 therein with a reference to Section 10.08.





(c)  Article X
of the Original Indenture is amended by adding a new Section 10.08 thereto
immediately following Section 10.07 thereof, such Section 10.08 to read as
follows:





"Section
10.08. Limitation
upon Mortgages and Liens .





The
Company will not at any time directly or indirectly create or assume and will
not cause or permit a Subsidiary directly or indirectly to create or assume,
except in favor of the Company or a Wholly-Owned Subsidiary, any mortgage,
pledge or other lien or encumbrance upon any Principal Facility or any interest
it may have therein or upon any stock of any Regulated Subsidiary or any
indebtedness of any Subsidiary to the Company or any other Subsidiary, whether
now owned or hereafter acquired, without making effective provision (and the
Company covenants that in such case it will make or cause to be made, effective
provision) whereby the outstanding Securities and any other indebtedness of the
Company then entitled thereto shall be secured by such mortgage, pledge, lien or
encumbrance equally and ratably with any and all other obligations and
indebtedness thereby secured, so long as any such other obligations and
indebtedness shall be so secured (provided, that for the purpose of providing
such equal and ratable security, the principal amount of outstanding Original
Issue Discount Securities shall be the amount of the principal thereof that
would be due and payable as of the date of such determination upon a declaration
of acceleration of the Maturity thereof pursuant to Section 5.02); provided,
however, that the foregoing covenant shall not be applicable to (1) the lien of
the Midwest Power Indenture, (2) Permitted Encumbrances or (3) any transfer,
lease, use or other encumbrance of or on the Company’s or any Subsidiary’s
transmission assets as required by applicable state or federal order,
regulation, rule or statute."








7











(e)  The first
sentence of Section 14.03 of the Original Indenture is hereby amended by
replacing the references to Section 10.04 therein with references to Section
10.08 in each place where such references appear in such sentence.





Section
4.02. Application of Amendments. The amendments to the Original Indenture set
forth in Section 4.01 hereof shall be applicable only to the Securities, and
shall not be applicable to any other series of securities issued under the
Original Indenture except as otherwise provided in a supplemental indenture
related to such other series of securities.





ARTICLE
V


MISCELLANEOUS





Section
5.01. Execution as Supplemental Indenture. This Third Supplemental Indenture is
executed and shall be construed as an indenture supplemental to the Original
Indenture and, as provided in the Original Indenture, this Third Supplemental
Indenture forms a part thereof.





Section
5.02. Effect of Headings. The Article and Section headings herein are for
convenience only and shall not affect the construction hereof.





Section
5.03. Successors and Assigns. All covenants and agreements contained in this
Third Supplemental Indenture made by the Company shall bind its successors and
assigns, whether so expressed or not.


Section
5.04. Separability Clause. In case any provision in this Third Supplemental
Indenture or in the Securities shall be invalid, illegal or unenforceable, the
validity, legality and enforceability of the remaining provisions shall not in
any way be affected or impaired thereby.





Section
5.05. Benefits of Third Supplemental Indenture. Nothing in this Third
Supplemental Indenture or in the Securities, express or implied, shall give to
any person, other than the parties hereto and their successors hereunder and the
Holders of the Securities, any benefit or any legal or equitable right, remedy
or claim under this Third Supplemental Indenture.





Section
5.06. Execution and Counterparts. This Third Supplemental Indenture may be
executed in any number of counterparts, each of which shall be deemed to be an
original, but all such counterparts shall together constitute but one and the
same instrument.








8











Section
5.07. Trustee Not Responsible for Recitals. The recitals herein contained are
made by the Company and not by the Trustee, and the Trustee assumes no
responsibility for the correctness thereof. The Trustee makes no representation
as to the validity or sufficiency of this Third Supplemental Indenture or of the
Securities. The Trustee shall not be accountable for the use or application by
the Company of the Securities or the proceeds thereof.





[SIGNATURE
PAGE FOLLOWS]









9








IN
WITNESS WHEREOF, the parties hereof have caused this Third Supplemental
Indenture to be duly executed by their respective officers or directors duly
authorized thereto, all as of the day and year first above written.











MIDAMERICAN
      ENERGY COMPANYBy:/s/Brian
      K. HankelName: 
      Brian K. HankelTitle:THE
      BANK OF NEW YORKas
      TrusteeBy: 
      /s/  Robert A. MassimilloName: 
      Robert A. MassimilloTitle:







10