20260615Compliance Filing.pdf

I v2r"
RECEIVED
AUNE 11, 2026
vista Corp.Cor
p• IDAHO PUBLIC
1411 East Mission P.O. Box 3727 UTILITIES COMMISSION
Spokane, Washington 99220-0500
Telephone [phone]
Toll Free 800-727-9170
June 11, 2026
State of Idaho
Idaho Public Utilities Commission
11331 W. Chinden Blvd
Bldg 8 Suite 201-A
Boise, ID 83714
RE: Filing requirements under Order No. 36079
Dear Commission Secretary:
Enclosed is the Seventieth Supplemental Indenture and Summary Term Sheet
pertaining to the May 14, 2026 debt issuance and expected August 2026 debt issuance,
as required under Order No. 36079. If any questions arise or additional information is
needed, please do not hesitate to contact Krista Johnson at 509-495-8020.
Sincerely,
Jason E. Lang
Director of Finance, Risk and Assistant Treasurer
Enclosures

AVISTA CORPORATION
TO
CITIBANK,N.A.
As Successor Trustee under
Mortgage and Deed of Trust,
dated as of June 1, 1939
Seventieth Supplemental Indenture
Providing among other things for two series of bonds designated
"First Mortgage Bonds, 4.77%Series due 2029"
Due May 1, 2029
and
"First Mortgage Bonds, 6.10%Series due 2056"
Due May 1, 2056
Dated as of May 1, 2026
IM411025280.6

SEVENTIETH SUPPLEMENTAL INDENTURE
THIS INDENTURE, dated as of the 1' day of May, 2026, between AVISTA
CORPORATION (formerly known as The Washington Water Power Company), a corporation of
the State of Washington, whose post office address is 1411 East Mission Avenue, Spokane,
Washington 99202 (the "Company"), and CITIBANK, N.A., formerly First National City Bank
(successor by merger to First National City Trust Company, formerly City Bank Farmers Trust
Company), a national banking association incorporated and existing under the laws of the United
States of America, whose post office address is 388 Greenwich Street, New York, New York
10013, as trustee (the "Trustee"), under the Mortgage and Deed of Trust, dated as of June 1, 1939
(the "Original Mortgage"), executed and delivered by the Company to secure the payment of
bonds issued or to be issued under and in accordance with the provisions thereof, this indenture
(this "Seventieth Supplemental Indenture") being supplemental to the Original Mortgage, as
heretofore supplemented and amended.
WHEREAS pursuant to a written request of the Company made in accordance
with Section 103 of the Original Mortgage, Francis M. Pitt (then Individual Trustee under the
Original Mortgage, as theretofore supplemented and amended) ceased to be a trustee thereunder
on July 23, 1969, and all of his powers as Individual Trustee have devolved upon the Trustee and
its successors alone; and
WHEREAS by the Original Mortgage the Company covenanted that it would
execute and deliver such further instruments and do such further acts as might be necessary or
proper to carry out more effectually the purposes of the Original Mortgage and to make subject
to the lien of the Original Mortgage any property thereafter acquired intended to be subject to the
lien thereof; and
WHEREAS the Company has heretofore executed and delivered, in addition to
the Original Mortgage, the indentures supplemental thereto and amendatory thereof, and has
issued the series of bonds, set forth in Exhibit A hereto (the Original Mortgage, as supplemented
and amended by the First through Sixty-ninth Supplemental Indentures and, if the context shall
so require, as to be supplemented by this Seventieth Supplemental Indenture, being herein
sometimes called the "Mortgage"); and
WHEREAS the Original Mortgage and the First Supplemental Indenture, dated as
of October 1, 1952, through the Twenty-fifth Supplemental Indenture, dated as of October 1,
1989, were appropriately filed and recorded in the various official records in the States of
Washington, Idaho and Montana, as set forth in such Supplemental Indentures and in the
Twenty-sixth Supplemental Indenture, dated as of April 1, 1993; and
WHEREAS for the purpose of confirming or perfecting the lien of the Original
Mortgage, as then supplemented and amended, on additional properties of the Company located
in the State of Oregon and additional counties in the State of Montana, the Company executed
and delivered a Short Form Mortgage and Security Agreement, in multiple counterparts dated as
of various dates in 1992, in furtherance of and supplemental to the Original Mortgage, as then
supplemented and amended, and such instrument was appropriately filed and recorded in the
1

various official records in Oregon and Montana, as set forth in the aforesaid Twenty-sixth
Supplemental Indenture; and
WHEREAS the aforesaid Twenty-sixth Supplemental Indenture through the
Twenty-ninth Supplemental Indenture, dated as of December 1, 2001, were appropriately filed
and recorded in the various official records in the States of Washington, Idaho, Montana and
Oregon, as set forth in the Twenty-seventh Supplemental Indenture, dated as of January 1, 1994,
through the Thirtieth Supplemental Indenture, dated as of May 1, 2002; and
WHEREAS for the purpose of confirming or perfecting the lien of the Original
Mortgage, as then supplemented and amended, on all its properties (other than specifically
excepted property), including all real properties owned in fee, which were specifically described
or referred to in Exhibit B to such instrument, all easements and other interests in and rights to
use real property and all equipment and fixtures, the Company executed and delivered an
Instrument of Further Assurance, dated as of December 15, 2001, in furtherance of and
supplemental to the Original Mortgage, as then supplemented and amended, and such instrument
was appropriately filed and recorded in the various official records in the States of Washington,
Idaho, Montana and Oregon; and
WHEREAS for the purpose of confirming or perfecting the lien of the Original
Mortgage, as then supplemented and amended, on additional properties of the Company located
in an additional county in the State of Oregon, the Company executed and delivered a
Memorandum of Mortgage and Security Agreement, dated as of May 29, 2003, in furtherance of
and supplemental to the Original Mortgage, as then supplemented and amended, and such
instrument was appropriately filed and recorded in the various official records in the State of
Oregon; and
WHEREAS the aforesaid Thirtieth Supplemental Indenture through the Sixty-
eighth Supplemental Indenture, dated as of June 1, 2023, were appropriately filed and recorded
in the various official records in the States of Washington, Idaho, Montana and Oregon, as set
forth in the Thirty-first Supplemental Indenture, dated as of May 1, 2003, through the Sixty-ninth
Supplemental Indenture, dated as of July 1, 2025; and
WHEREAS the aforesaid Sixty-ninth Supplemental Indenture, dated as of July 1,
2025, has been appropriately filed or recorded in the various official records in the States of
Washington, Idaho, Montana and Oregon, as set forth in Exhibit B hereto; and
WHEREAS in addition to the property described in the Mortgage the Company
has acquired certain other property, rights and interests in property; and
WHEREAS Section 120 of the Original Mortgage, as heretofore amended,
provides that, without the consent of any holders of bonds, the Company and the Trustee, at any
time and from time to time, may enter into indentures supplemental to the Original Mortgage for
various purposes set forth therein, including, without limitation, to cure ambiguities or correct
defective or inconsistent provisions or to make other changes therein that shall not adversely
affect the interests of the holders of bonds of any series in any material respect or to establish the
form or terms of bonds of any series as contemplated by Article II; and
2

WHEREAS the Company now desires to create two new series of bonds; and
WHEREAS Section 8 of the Original Mortgage, as heretofore amended, provides
that the form of each series of bonds (other than the First Series) issued thereunder and of the
coupons to be attached to coupon bonds of such series shall be established by Resolution of the
Board of Directors of the Company or by Treasurer's Certificate, or shall be set forth in an
indenture supplemental to the Original Mortgage; that the form of such series, as so established,
shall specify the descriptive title of the bonds and various other terms thereof, and that such
series may also contain such provisions not inconsistent with the provisions of the Mortgage as
the Company may, in its discretion, cause to be inserted therein expressing or referring to the
terms and conditions upon which such bonds are to be issued and/or secured under the Mortgage;
and
WHEREAS the execution and delivery by the Company of this Seventieth
Supplemental Indenture and the terms of the Bonds of the Seventy-first Series and the Bonds of
the Seventy-second Series, each hereinafter referred to, have been duly authorized by all
necessary corporate action including appropriate Resolutions of the Board of Directors of the
Company, and all things necessary to make this Seventieth Supplemental Indenture a valid,
binding and legal instrument have been performed;
NOW, THEREFORE, THIS INDENTURE WITNESSETH: That the Company,
in consideration of the premises and of other good and valuable consideration, the receipt and
sufficiency whereof are hereby acknowledged, hereby confirms the estate, title and rights of the
Trustee (including, without limitation, the lien of the Mortgage on the property of the Company
subjected thereto, whether now owned or hereafter acquired) held as security for the payment of
both the principal of and interest and premium, if any, on the bonds from time to time issued
under the Mortgage according to their tenor and effect and the performance of all the provisions
of the Mortgage and of such bonds, and, without limiting the generality of the foregoing, hereby
confirms the grant, bargain, sale, release, conveyance, assignment, transfer, mortgage, pledge,
setting over and confirmation unto the Trustee, contained in the Mortgage, of all the following
described properties of the Company, whether now owned or hereafter acquired, namely:
All of the property, real, personal and mixed, of every character and
wheresoever situated (except any hereinafter or in the Mortgage expressly
excepted) which the Company now owns or, subject to the provisions of
Section 87 of the Original Mortgage, may hereafter acquire prior to the
satisfaction and discharge of the Mortgage, as fully and completely as if herein or
in the Mortgage specifically described, and including (without in anywise limiting
or impairing by the enumeration of the same the scope and intent of the foregoing
or of any general description contained in Mortgage) all lands, real estate,
easements, servitudes, rights of way and leasehold and other interests in real
estate; all rights to the use or appropriation of water, flowage rights, water storage
rights, flooding rights, and other rights in respect of or relating to water; all plants
for the generation of electricity, power houses, dams, dam sites, reservoirs,
flumes, raceways, diversion works, head works, waterways, water works, water
systems, gas plants, steam heat plants, hot water plants, ice or refrigeration plants,
stations, substations, offices, buildings and other works and structures and the
3

equipment thereof and all improvements, extensions and additions thereto; all
generators, machinery, engines, turbines, boilers, dynamos, transformers, motors,
electric machines, switchboards, regulators, meters, electrical and mechanical
appliances, conduits, cables, pipes and mains; all lines and systems for the
transmission and distribution of electric current, gas, steam heat or water for any
purpose; all towers, mains, pipes, poles, pole lines, conduits, cables, wires, switch
racks, insulators, compressors, pumps, fittings, valves and connections; all tools,
implements, apparatus, furniture, stores, supplies and equipment; all franchises
(except the Company's franchise to be a corporation), licenses, permits, rights,
powers and privileges; and (except as hereinafter or in the Mortgage expressly
excepted) all the right, title and interest of the Company in and to all other
property of any kind or nature.
The Company hereby acknowledges that, as of the date of this Seventieth
Supplemental Indenture, the real property located in the State of Washington, taken as a whole,
that is so conveyed or intended to be so conveyed under the Mortgage is not used principally for
agricultural purposes.
The property so conveyed or intended to be so conveyed under the Mortgage shall
include, but shall not be limited to, the property set forth in Exhibit C hereto, the particular
description of which is intended only to aid in the identification thereof and shall not be
construed as limiting the force, effect and scope of the foregoing.
TOGETHER WITH all and singular the tenements, hereditaments and
appurtenances belonging or in anywise appertaining to the aforesaid property or any part thereof,
with the reversion and reversions, remainder and remainders and (subject to the provisions of
Section 57 of the Original Mortgage) the tolls, rents, revenues, issues, earnings, income, product
and profits thereof, and all the estate, right, title and interest and claim whatsoever, at law as well
as in equity, which the Company now has or may hereafter acquire in and to the aforesaid
property and franchises and every part and parcel thereof.
THE COMPANY HEREBY CONFIRMS that, subject to the provisions of
Section 87 of the Original Mortgage, all the property, rights, and franchises acquired by the
Company after the date of the Original Mortgage (except any in the Mortgage expressly
excepted) are and shall be as fully embraced within the lien of the Mortgage as if such property,
rights and franchises had been owned by the Company at the date of the Original Mortgage and
had been specifically described therein.
PROVIDED THAT the following were not and were not intended to be then or
now or hereafter granted, bargained, sold, released, conveyed, assigned, transferred, mortgaged,
pledged, set over or confirmed under the Mortgage and were, are and shall be expressly excepted
from the lien and operation of the Mortgage namely: (1) cash, shares of stock and obligations
(including bonds, notes and other securities)not hereafter specifically pledged,paid, deposited or
delivered under the Mortgage or covenanted so to be; (2)merchandise, equipment, materials or
supplies held for the purpose of sale in the usual course of business or for consumption in the
operation of any properties of the Company; (3) bills, notes and accounts receivable, and all
contracts, leases and operating agreements not specifically pledged under the Mortgage or
4

covenanted so to be; (4) electric energy and other materials or products generated, manufactured,
produced or purchased by the Company for sale, distribution or use in the ordinary course of its
business; (5) all automobiles, buses, trucks, truck cranes, tractors, trailers and similar vehicles
and movable equipment; all rolling stock, rail cars and other railroad equipment; all vessels,
boats, barges, and other marine equipment; all airplanes, helicopters, drones, aircraft engines and
other flight equipment; all parts, accessories and supplies used in connection with any of the
foregoing; and all personal property of such character that the perfection of a security interest
therein or other lien thereon is not governed by the Uniform Commercial Code (or similar law)
as in effect in the jurisdiction in which such property is located; and (6) any property released
pursuant to any provisions of the Mortgage and not disposed of by the Company and
improvements, extensions and additions thereto and renewals and replacements thereof;
provided, however, that the property and rights expressly excepted from the lien and operation of
the Mortgage in the above subdivisions (2) and (3) shall (to the extent permitted by law) cease to
be so excepted in the event that the Trustee or a receiver or trustee shall enter upon and take
possession of the Mortgaged and Pledged Property in the manner provided in Article XII of the
Original Mortgage by reason of the occurrence of a Completed Default as defined in said
Article XII of the Original Mortgage, as heretofore amended.
TO HAVE AND TO HOLD all such properties, real, personal and mixed,
granted, bargained, sold, released, conveyed, assigned, transferred, mortgaged, pledged, set over
or confirmed by the Company in the Mortgage as aforesaid, or intended so to be, unto the
Trustee, and its successors, heirs and assigns forever.
IN TRUST NEVERTHELESS, for the same purposes and upon the same terms,
trusts and conditions and subject to and with the same provisos and covenants as set forth in the
Mortgage, this Seventieth Supplemental Indenture being supplemental to the Mortgage.
AND IT IS HEREBY FURTHER CONFIRMED by the Company that all the
terms, conditions, provisos, covenants and provisions contained in the Mortgage shall affect and
apply to the property in the Mortgage described and conveyed, and to the estates, rights,
obligations and duties of the Company and the Trustee and the beneficiaries of the trust with
respect to said property, and to the Trustee and its successors in the trust, in the same manner and
with the same effect as if the said property had been owned by the Company at the time of the
execution of the Original Mortgage, and had been specifically and at length described in and
conveyed to said Trustee by the Original Mortgage as a part of the property therein stated to be
conveyed.
The Company further covenants and agrees to and with the Trustee and its
successor or successors in such trust under the Mortgage, as follows:
ARTICLE I
Seventy-first Series of Bonds
SECTION 1. (I) There shall be a series of bonds designated "First Mortgage
Bonds, 4.77% Series due 2029" (herein sometimes referred to as the 'Bonds of the Seventy-first
Series"), each of which shall also bear the descriptive title First Mortgage Bond, and the form
5

thereof is set forth on Exhibit D hereto. The Bonds of the Seventy-first Series shall be issued as
fully registered bonds in denominations of One Thousand Dollars and, at the option of the
Company, any amount in excess thereof (the exercise of such option to be evidenced by the
execution and delivery thereof) and shall be dated as in Section 10 of the Original Mortgage
provided.
(II) The Bonds of the Seventy-first Series shall have the following terms and
characteristics:
(a) the Bonds of the Seventy-first Series shall be limited in aggregate
principal amount to $90,000,000 (except for Bonds of such series authenticated and
delivered upon transfer of or in exchange for, or in lieu of, other Bonds of such series);
(b) the principal of the Bonds of the Seventy-first Series shall (unless
theretofore paid)be payable on the Stated Maturity Date (as hereinafter defined);
(c) the Bonds of the Seventy-first Series shall bear interest at the rate
of four and seventy-seven one-hundredths per centum (4.77%) per annum; interest on the
Bonds of such series shall accrue from and including May 14, 2026, except as otherwise
provided in the form of bond attached hereto as Exhibit D; interest on the Bonds of such
series shall be payable on each Interest Payment Date and at Maturity (each as hereinafter
defined); and interest on the Bonds of such series during any period less than one year for
which payment is made shall be computed on the basis of a 360-day year consisting of
twelve 30-days months;
(d) the principal of and premium, if any, and interest on each Bond of
the Seventy-first Series payable at Maturity shall be payable to the registered owner
thereof upon presentation thereof at the office or agency of the Company in the Borough
of Manhattan, The City of New York, in such coin or currency of the United States of
America as at the time of payment is legal tender for public and private debts. The
interest on each Bond of the Seventy-first Series (other than interest payable at Maturity)
shall be payable by check, in similar coin or currency, mailed to the registered owner
thereof as of the close of business on the Record Date (as hereinafter defined) next
preceding each Interest Payment Date; provided, however, that if such registered owner
shall be a securities depositary, such payment may be made by such other means in lieu
of check as shall be agreed upon by the Company, the Trustee and such registered owner;
and, provided, further, that, so long as any Bond of the Seventy-first Series shall be held
by (i) the original purchaser thereof under the Bond Purchase Agreement (as hereinafter
defined) or (ii) any other Institutional Investor (as hereinafter defined) that (A) is the
direct or indirect transferee of such Bond from such original purchaser and (B) has made
the same agreement relating to such Bond as such original purchaser made in Section 8.2
of the Bond Purchase Agreement, payment of principal of and premium, if any, and
interest on such Bond of the Seventy-first Series shall be payable in the manner specified
in the Bond Purchase Agreement. Interest payable at Maturity shall be paid to the person
to whom principal shall be paid.
6

(e) (i) Prior to the Par Call Date (as hereinafter defined), the
Bonds of the Seventy-first Series shall be redeemable in whole at any time, or in part
from time to time, at the option of the Company at a redemption price equal to the greater
of
(A) 100% of the principal amount of the Bonds of such series
being redeemed and
(B) (I) the sum of the present values of the remaining
scheduled payments of principal of and interest on the Bonds of such
series being redeemed (assuming, for this purpose, that the Bonds of such
series were stated to mature on the Par Call Date), discounted to the date
of redemption on a semiannual basis (assuming a 360-day year consisting
of twelve 30-day months) at a discount rate equal to the Treasury Yield(as
hereinafter defined) plus 50 basis points, less (II) interest accrued to the
redemption date,
plus, in the case of either (A) or (B) above, whichever is applicable, accrued and unpaid
interest on such Bonds to the date of redemption.
(ii) On or after the Par Call Date, the Bonds of the Seventy-first
Series shall be redeemable in whole at any time, or in part from time to time, at the option
of the Company at a redemption price equal to 100% of the principal amount of the
Bonds of such series being redeemed plus accrued and unpaid interest on such Bonds to
the date of redemption.
(f) (i) 'Par Call Date", with respect to the Bonds of the Seventy-
first Series, means April 1, 2029;
(ii) "Treasury Yield" means, with respect to any redemption of
Bonds of the Seventy-first Series, the yield to maturity determined as follows for the
latest day for which yields for Treasury constant maturities are reported on H.15 (as
hereinafter defined) as of the Calculation Date (as hereinafter defined):
(A) the yield for the Treasury constant maturity on H.15 exactly
equal to the period from the redemption date to the Par Call Date (the
"Remaining Life"); or
(B) if there is no such Treasury constant maturity on H.15
having a term exactly equal to the Remaining Life, the yield to maturity
determined by linear interpolation on a straight-line basis between (I) the
yield for the Treasury constant maturity reported on H.15 with the term
next longer than the Remaining Life and (II) the yield for the Treasury
constant maturity so reported with the term next shorter than the
Remaining Life, or
(C) if there is no such Treasury constant maturity on H.15
shorter than the Remaining Life, or there is no such Treasury constant
7

maturity on H.15 longer than the Remaining Life, the yield for the single
Treasury constant maturity on H.15 closest to the Remaining Life.
The Treasury Yield shall be rounded to three decimal places. The Treasury Yield shall
be calculated as of the third Business Day (as hereinafter defined) preceding the earlier of
(X) the date notice of redemption is mailed to holders of Bonds of the Seventy-first
Series and (Y) the date irrevocable arrangements with the Trustee for the mailing of such
notice shall have been made, as the case may be (the "Calculation Date"). For purposes
of this paragraph, the applicable Treasury constant maturity shall be deemed to have a
term equal to the number of years, months and days, as applicable, from the redemption
date of the Bonds to be redeemed to the Par Call Date.
If, on the third business day preceding the Calculation Date, H.15 is no longer
published or, if published, no longer contains the yields for nominal Treasury constant
maturities, the Treasury yield shall be the rate per annum equal to the semi-annual
equivalent yield to maturity at 11:00 a.m., New York City time, on the second business
day preceding the Calculation Date of:
(A) the United States Treasury security maturing on, or with a
maturity that is closest to, the Par Call Date, as applicable, in either case
subject to clause (C)below; or
(B) if there is no United States Treasury security maturing on
the Par Call Date but there are two or more United States Treasury
securities with a maturity date equally distant from the Par Call Date, one
with a maturity date preceding the Par Call Date and one with a maturity
date following the Par Call Date, the United States Treasury security with
a maturity date next preceding the Par Call Date, subject to clause (C)
below; or
(C) if there are two or more United States Treasury securities
maturing on the Par Call Date or two or more United States Treasury
securities otherwise meeting the criteria of clause (A) or clause (B) above,
the United States Treasury security that is trading closest to par based
upon the average of the bid and asked prices for such securities at such
time.
In determining the Treasury yield in accordance with this paragraph, the semi-annual
yield to maturity of the applicable United States Treasury security shall be based upon the
average of the bid and asked prices (expressed as a percentage of principal amount) at
11:00 a.m., New York City time, of such United States Treasury security, rounded to
three decimal places.
(iii) "H.15" means the daily statistical release entitled "Selected
Interest Rates (Daily) — H.15", or any successor publication, published by the Board of
Governors of the Federal Reserve System, or any successor entity; or, if such Board of
Governors no longer publishes the information contained in such statistical release, a
8

publication containing similar information published by the U.S. Department of the
Treasury, or any successor or other U.S. governmental body; and, in any case, references
to H.15 shall be deemed to contemplate, in particular, the information under the caption
"U.S. governmental securities — Treasury constant maturities — Nominal" (or any
successor caption or heading containing similar information).
(iv) The Company's actions and determinations in determining
the redemption price shall be conclusive and binding for all purposes, absent manifest
error.
(g) If less than all of the outstanding Bonds of the Seventy-first Series
are to be redeemed in accordance with paragraph (h) above, the principal amount to be
redeemed shall be prorated among all of the holders of the Bonds of such series in the
proportion that their respective holdings bear to the aggregate principal amount of such
Bonds outstanding on the date of selection. The portion of any Bond of such series to be
redeemed shall be in the principal amount of$1,000 or an integral multiple thereof and
such rounding allocations as may be requisite for this purpose shall be made by the
Trustee in its uncontrolled discretion. The Trustee shall promptly notify the Company in
writing of the distinctive numbers of the Bonds of such series and the portions thereof so
selected for redemption.
(h) (i) If the Company shall have reasonably determined that it is
reasonably likely that any Purchaser (as hereinafter defined) is a "specified foreign
entity" (as defined in Section 7701(a)(51)(B) of the Internal Revenue Code of 1986, as
amended), then the Bonds of the Seventy-first Series held by such Purchaser shall be
redeemable in whole at any time, or in part from time to time, at the option of the
Company, at a redemption price of 100% of the principal amount of the Bonds to be
redeemed plus accrued and unpaid interest to the date of redemption. If there shall be
more than one such Purchaser, the Company shall determine the Purchaser or Purchasers
whose Bonds of the Seventy-first Series are to be redeemed in accordance with this
paragraph (h) and the principal amount of Bonds of each such Purchaser to be redeemed
and shall notify the Trustee thereof. Notwithstanding Section 52 of the Original
Mortgage, as heretofore amended, notice of redemption of Bonds under this paragraph
(h) shall be given not less than five (5) Business Days before the date fixed for
redemption.
(ii) The Company's determinations under this paragraph (h)
shall be conclusive and binding for all purposes, absent manifest error. The Trustee shall
have no duty to verify or investigate the Company's determinations under this paragraph
(h).
(i) Except as provided in this subsection (II) of Section 1,
(i) the Bonds of the Seventy-first Series shall not be
redeemable prior to the Stated Maturity Date; and
9

(ii) no amount other than the principal of and interest on the
Bonds of the Seventy-first Series shall be payable in respect of the Bonds of the Seventy-
first Series at Maturity (as hereinafter defined) or otherwise.
0) in the event of any conflict between the provisions of Section
12.2(c) of the Bond Purchase Agreement and the provisions of the Mortgage, Section
12.2(c) of the Bond Purchase Agreement shall govern.
(III) At the option of the registered owner, any Bonds of the Seventy-first
Series, upon surrender thereof for cancellation at the office or agency of the Company in the
Borough of Manhattan, The City of New York, shall be exchangeable for a like aggregate
principal amount of Bonds of the same series of other authorized denominations.
The Bonds of the Seventy-first Series shall be transferable, upon the surrender
thereof for cancellation, together with a written instrument of transfer in form approved by the
registrar duly executed by the registered owner or by his duly authorized attorney, at the office or
agency of the Company in the Borough of Manhattan, The City of New York.
Upon any exchange or transfer of Bonds of the Seventy-first Series, the Company
may make a charge therefor sufficient to reimburse it for any tax or taxes or other governmental
charge, as provided in Section 12 of the Original Mortgage, but the Company hereby waives any
right to make a charge in addition thereto or any exchange or transfer of Bonds of the Seventy-
first Series; provided, however, that the Company shall not be required to make any transfer or
exchange of any Bonds of the Seventy-first Series for a period of 10 days next preceding any
Interest Payment Date or any selection of such Bonds for redemption, nor shall it be required to
make any transfer or exchange of any Bonds of the Seventy-first Series which shall have been
selected for redemption in whole or in part.
Unless and until the Company shall have delivered to the Trustee a written order
to the contrary, the Bonds of the Seventy-first Series shall bear a legend as to restrictions on
transfer substantially as set forth below:
The Bonds evidenced hereby have not been registered under the Securities
Act of 1933, as amended (the "Securities Act"), and may not be offered,
sold, pledged or otherwise transferred in contravention of the Securities
Act.
(IV) For all purposes of this Seventieth Supplemental Indenture, except as
otherwise expressly provided or unless the context otherwise requires, the terms listed below,
when used with respect to the Bonds of the Seventy-first Series, shall have the meanings
specified below:
"Bond Purchase Agreement" means the Bond Purchase Agreement, dated May
14, 2026, relating to the Bonds of the Seventy-first Series, between the Company and the
purchasers listed on Schedule A thereto.
"Business Day" means any day, other than a Saturday or Sunday, which is not a
day on which banking institutions or trust companies in The City of New York, New
10

York are generally authorized or required by law, regulation or executive order to remain
closed.
"Institutional Investor" means (a) any original purchaser of a Bond of the
Seventy-first Series, (b) any holder of a Bond of the Seventy-first Series holding
(together with one or more of its affiliates) more than $1,000,000 in aggregate principal
amount of the Bonds of the Seventy-first Series, and(c) any bank, trust company, savings
and loan association or other financial institution, any pension plan, any investment
company, any insurance company, any broker or dealer, or any other similar financial
institution or entity, regardless of legal form.
"Interest Payment Date" means May 1 and November 1 in each year,
commencing November 1, 2026.
"Maturity" means the date on which the principal of the Bonds of the Seventy-
first Series becomes due and payable, whether at the Stated Maturity Date, upon
redemption or acceleration, or otherwise.
"Purchaser" means any purchaser listed on Schedule A to the related Bond
Purchase Agreement.
"Record Date", with respect to any Interest Payment Date, means the close of
business on the seventh Business Day preceding such Interest Payment Date.
"Stated Maturity Date" means May 1, 2029.
(V) Notwithstanding the provisions of Section 106 of the Original Mortgage,
as amended, the Company shall not cause any Bonds of the Seventy-first Series, or any portion
of the principal amount thereof, to be deemed to have been paid as provided in such Section and
its obligations in respect thereof to be deemed to be satisfied and discharged prior to the Maturity
thereof unless the Company shall deliver to the Trustee either:
(a) an instrument wherein the Company, notwithstanding the effect of
Section 106 of the Original Mortgage, as amended, in respect of such Bonds of the
Seventy-first Series, shall assume the obligation (which shall be absolute and
unconditional) to irrevocably deposit with the Trustee such additional sums of money, if
any, or additional government obligations (meeting the requirements of Section 106), if
any, or any combination thereof, at such time or times, as shall be necessary, together
with the money and/or government obligations theretofore so deposited, to pay when due
the principal of and premium, if any, and interest due and to become due on such Bonds
or portions thereof, all in accordance with and subject to the provisions of Section 106;
provided, however, that such instrument may state that the obligation of the Company to
make additional deposits as aforesaid shall be subject to the delivery to the Company by
the Trustee of a notice asserting the deficiency accompanied by an opinion of an
independent accountant showing the calculation thereof(which opinion shall be obtained
at the expense of the Company); or
11

(b) an Opinion of Counsel to the effect that the holders of such Bonds
of the Seventy-first Series, or portions of the principal amount thereof, will not recognize
income, gain or loss for United States federal income tax purposes as a result of the
satisfaction and discharge of the Company's indebtedness in respect thereof and will be
subject to United States federal income tax on the same amounts, at the same times and in
the same manner as if such satisfaction and discharge had not been effected.
(VI) Anything in this Seventieth Supplemental Indenture or the Bonds of the
Seventy-first Series to the contrary notwithstanding, any payment of principal of or premium, if
any, or interest on any Bond of the Seventy-first Series that is due on a date other than a Business
Day shall be made on the next succeeding Business Day without including the additional days
elapsed in the computation of the interest payable on such next succeeding Business Day;
provided, however, that if the Maturity date of any Bond of the Seventy-first Series is a date
other than a Business Day, the payment otherwise due at Maturity shall be made on the next
succeeding Business Day and shall include the additional days elapsed in the computation of
interest payable on such next succeeding Business Day.
(VII) The Bonds of the Seventy-first Series shall have such further terms as are
set forth in Exhibit D hereto. If there shall be a conflict between the terms of the form of bond
and the provisions of the Mortgage, the provisions of the Mortgage shall control to the extent
permitted by law.
ARTICLE II
Seventy-second Series of Bonds
SECTION 1. (I) There shall be a series of bonds designated "First Mortgage
Bonds, 6.10% Series due 2056" (herein sometimes referred to as the "Bonds of the Seventy-
second Series"), each of which shall also bear the descriptive title First Mortgage Bond, and the
form thereof is set forth on Exhibit E hereto. The Bonds of the Seventy-second Series shall be
issued as fully registered bonds in denominations of One Thousand Dollars and, at the option of
the Company, any amount in excess thereof(the exercise of such option to be evidenced by the
execution and delivery thereof) and shall be dated as in Section 10 of the Original Mortgage
provided.
(II) The Bonds of the Seventy-second Series shall have the following terns
and characteristics:
(a) the Bonds of the Seventy-second Series shall be limited in
aggregate principal amount to $140,000,000 (except for Bonds of such series
authenticated and delivered upon transfer of or in exchange for, or in lieu of, other Bonds
of such series);
(b) the Bonds of the Seventy-second Series may be authenticated and
delivered in whole at any time or in part from time to time; all Bonds of the Seventy-
second Series shall be identical in all respects, except that any such Bonds originally
authenticated and delivered on different dates shall differ as to the Initial Interest Accrual
12

Date (as hereinafter defined); and on and after the first Interest Payment Date (as
hereinafter defined) to which interest on all Bonds of the Seventy-second Series then
outstanding has been paid, all such Bonds shall be identical in all respects.
(c) the principal of the Bonds of the Seventy-second Series shall
(unless theretofore paid)be payable on the Stated Maturity Date (as hereinafter defined);
(d) the Bonds of the Seventy-second Series shall bear interest at the
rate of six and ten one-hundredths per centum (6.10%) per annum; interest on the Bonds
of such series shall accrue from the Initial Interest Accrual Date (as hereinafter defined),
except as otherwise provided in the form of bond attached hereto as Exhibit E; interest on
the Bonds of such series shall be payable on each Interest Payment Date and at Maturity
(each as hereinafter defined); and interest on the Bonds of such series during any period
less than one year for which payment is made shall be computed on the basis of a 360-
day year consisting of twelve 30-days months;
(e) the principal of and premium, if any, and interest on each Bond of
the Seventy-second Series payable at Maturity shall be payable to the registered owner
thereof upon presentation thereof at the office or agency of the Company in the Borough
of Manhattan, The City of New York, in such coin or currency of the United States of
America as at the time of payment is legal tender for public and private debts. The
interest on each Bond of the Seventy-second Series (other than interest payable at
Maturity) shall be payable by check, in similar coin or currency, mailed to the registered
owner thereof as of the close of business on the Record Date (as hereinafter defined)next
preceding each Interest Payment Date; provided, however, that if such registered owner
shall be a securities depositary, such payment may be made by such other means in lieu
of check as shall be agreed upon by the Company, the Trustee and such registered owner;
and, provided, further, that, so long as any Bond of the Seventy-second Series shall be
held by (i) the original purchaser thereof under the Bond Purchase Agreement (as
hereinafter defined) or (ii) any other Institutional Investor (as hereinafter defined) that
(A) is the direct or indirect transferee of such Bond from such original purchaser and (B)
has made the same agreement relating to such Bond as such original purchaser made in
Section 8.2 of the Bond Purchase Agreement, payment of principal of and premium, if
any, and interest on such Bond of the Seventy-second Series shall be payable in the
manner specified in the Bond Purchase Agreement. Interest payable at Maturity shall be
paid to the person to whom principal shall be paid.
(f) (i) Prior to the Par Call Date (as hereinafter defined), the
Bonds of the Seventy-second Series shall be redeemable in whole at any time, or in part
from time to time, at the option of the Company at a redemption price equal to the greater
of
(A) 100% of the principal amount of the Bonds of such series
being redeemed and
(B) (1) the sum of the present values of the remaining
scheduled payments of principal of and interest on the Bonds of such
13

series being redeemed (assuming, for this purpose, that the Bonds of such
series were stated to mature on the Par Call Date), discounted to the date
of redemption on a semiannual basis (assuming a 360-day year consisting
of twelve 30-day months) at a discount rate equal to the Treasury Yield(as
hereinafter defined) plus 50 basis points, less (II) interest accrued to the
redemption date,
plus, in the case of either (A) or (B) above, whichever is applicable, accrued and unpaid
interest on such Bonds to the date of redemption.
(ii) On or after the Par Call Date, the Bonds of the Seventy-
second Series shall be redeemable in whole at any time, or in part from time to time, at
the option of the Company at a redemption price equal to 100% of the principal amount
of the Bonds of such series being redeemed plus accrued and unpaid interest on such
Bonds to the date of redemption.
(g) (i) "Par Call Date", with respect to the Bonds of the Seventy-
second Series, means November 1, 2055;
(ii) "Treasury Yield" means, with respect to any redemption of
Bonds of the Seventy-second Series, the yield to maturity determined as follows for the
latest day for which yields for Treasury constant maturities are reported on H.15 (as
hereinafter defined) as of the Calculation Date (as hereinafter defined):
(A) the yield for the Treasury constant maturity on H.15 exactly
equal to the period from the redemption date to the Par Call Date (the
"Remaining Life"); or
(B) if there is no such Treasury constant maturity on H.15
having a term exactly equal to the Remaining Life, the yield to maturity
determined by linear interpolation on a straight-line basis between (I) the
yield for the Treasury constant maturity reported on H.15 with the term
next longer than the Remaining Life and (II) the yield for the Treasury
constant maturity so reported with the term next shorter than the
Remaining Life, or
(C) if there is no such Treasury constant maturity on H.15
shorter than the Remaining Life, or there is no such Treasury constant
maturity on H.15 longer than the Remaining Life, the yield for the single
Treasury constant maturity on H.15 closest to the Remaining Life.
The Treasury Yield shall be rounded to three decimal places. The Treasury Yield shall
be calculated as of the third Business Day (as hereinafter defined)preceding the earlier of
(X) the date notice of redemption is mailed to holders of Bonds of the Seventy-second
Series and (Y) the date irrevocable arrangements with the Trustee for the mailing of such
notice shall have been made, as the case may be (the "Calculation Date"). For purposes
of this paragraph, the applicable Treasury constant maturity shall be deemed to have a
14

term equal to the number of years, months and days, as applicable, from the redemption
date of the Bonds to be redeemed to the Par Call Date.
If, on the third business day preceding the Calculation Date, H.15 is no longer
published or, if published, no longer contains the yields for nominal Treasury constant
maturities, the Treasury yield shall be the rate per annum equal to the semi-annual
equivalent yield to maturity at 11:00 a.m., New York City time, on the second business
day preceding the Calculation Date of:
(A) the United States Treasury security maturing on, or with a
maturity that is closest to, the Par Call Date, as applicable, in either case
subject to clause (C)below; or
(B) if there is no United States Treasury security maturing on
the Par Call Date but there are two or more United States Treasury
securities with a maturity date equally distant from the Par Call Date, one
with a maturity date preceding the Par Call Date and one with a maturity
date following the Par Call Date, the United States Treasury security with
a maturity date next preceding the Par Call Date, subject to clause (C)
below; or
(C) if there are two or more United States Treasury securities
maturing on the Par Call Date or two or more United States Treasury
securities otherwise meeting the criteria of clause (A) or clause (B) above,
the United States Treasury security that is trading closest to par based
upon the average of the bid and asked prices for such securities at such
time.
In determining the Treasury yield in accordance with this paragraph, the semi-annual
yield to maturity of the applicable United States Treasury security shall be based upon the
average of the bid and asked prices (expressed as a percentage of principal amount) at
11:00 a.m., New York City time, of such United States Treasury security, rounded to
three decimal places.
(iii) "H.15" means the daily statistical release entitled "Selected
Interest Rates (Daily) — H.15", or any successor publication, published by the Board of
Governors of the Federal Reserve System, or any successor entity; or, if such Board of
Governors no longer publishes the information contained in such statistical release, a
publication containing similar information published by the U.S. Department of the
Treasury, or any successor or other U.S. governmental body; and, in any case, references
to H.15 shall be deemed to contemplate, in particular, the information under the caption
"U.S. governmental securities — Treasury constant maturities — Nominal" (or any
successor caption or heading containing similar information).
(iv) The Company's actions and determinations in determining
the redemption price shall be conclusive and binding for all purposes, absent manifest
error.
15

(h) If less than all of the outstanding Bonds of the Seventy-second
Series are to be redeemed in accordance with paragraph (g) above, the principal amount
to be redeemed shall be prorated among all of the holders of the Bonds of such series in
the proportion that their respective holdings bear to the aggregate principal amount of
such Bonds outstanding on the date of selection. The portion of any Bond of such series
to be redeemed shall be in the principal amount of$1,000 or an integral multiple thereof
and such rounding allocations as may be requisite for this purpose shall be made by the
Trustee in its uncontrolled discretion. The Trustee shall promptly notify the Company in
writing of the distinctive numbers of the Bonds of such series and the portions thereof so
selected for redemption.
(i) (i) If the Company shall have reasonably determined that it is
reasonably likely that any Purchaser (as hereinafter defined) is a "specified foreign
entity" (as defined in Section 7701(a)(51)(B) of the Internal revenue Service Code of
1986, as amended), then the Bonds of the Seventy-second Series held by such Purchaser
shall be redeemable in whole at any time, or in part from time to time, at the option of the
Company, at a redemption price of 100% of the principal amount of the Bonds to be
redeemed plus accrued and unpaid interest to the date of redemption. If there shall be
more than one such Purchaser, the Company shall determine the Purchaser or Purchasers
whose Bonds of the Seventy-second Series are to be redeemed in accordance with this
paragraph (i) and the principal amount of Bonds of each such Purchaser to be redeemed
and shall notify the Trustee thereof. Notwithstanding Section 52 of the Original
Mortgage, as heretofore amended, notice of redemption of Bonds under this paragraph (i)
shall be given not less than five (5)Business Days before the date fixed for redemption.
(ii) The Company's determinations under this paragraph (i)
shall be conclusive and binding for all purposes, absent manifest error. The Trustee shall
have no duty to verify or investigate the Company's determinations under this paragraph
(i).
(j) Except as provided in this subsection(II) of Section 1,
(i) the Bonds of the Seventy-second Series shall not be
redeemable prior to the Stated Maturity Date; and
(ii) no amount other than the principal of and interest on the
Bonds of the Seventy-second Series shall be payable in respect of the Bonds of the
Seventy-second Series at Maturity(as hereinafter defined) or otherwise.
(k) in the event of any conflict between the provisions of Section
12.2(c) of the Bond Purchase Agreement and the provisions of the Mortgage, Section
12.2(c) of the Bond Purchase Agreement shall govern.
(III) At the option of the registered owner, any Bonds of the Seventy-second
Series, upon surrender thereof for cancellation at the office or agency of the Company in the
Borough of Manhattan, The City of New York, shall be exchangeable for a like aggregate
principal amount of Bonds of the same series of other authorized denominations.
16

The Bonds of the Seventy-second Series shall be transferable, upon the surrender
thereof for cancellation, together with a written instrument of transfer in form approved by the
registrar duly executed by the registered owner or by his duly authorized attorney, at the office or
agency of the Company in the Borough of Manhattan, The City of New York.
Upon any exchange or transfer of Bonds of the Seventy-second Series, the
Company may make a charge therefor sufficient to reimburse it for any tax or taxes or other
governmental charge, as provided in Section 12 of the Original Mortgage, but the Company
hereby waives any right to make a charge in addition thereto or any exchange or transfer of
Bonds of the Seventy-first Series; provided, however, that the Company shall not be required to
make any transfer or exchange of any Bonds of the Seventy-second Series for a period of 10
days next preceding any Interest Payment Date or any selection of such Bonds for redemption,
nor shall it be required to make any transfer or exchange of any Bonds of the Seventy-first Series
which shall have been selected for redemption in whole or in part.
Any Bond of the Seventy-second Series authenticated and delivered upon the
transfer or exchange of a Bond of such series prior to the first Interest Payment Date to which
interest on all outstanding Bonds of the Seventy-second Series has been paid shall have the same
Initial Interest Accrual Date as the Bond surrendered in such transfer or exchange.
Unless and until the Company shall have delivered to the Trustee a written order
to the contrary, the Bonds of the Seventy-second Series shall bear a legend as to restrictions on
transfer substantially as set forth below:
The Bonds evidenced hereby have not been registered under the Securities
Act of 1933, as amended (the "Securities Act"), and may not be offered,
sold, pledged or otherwise transferred in contravention of the Securities
Act.
(IV) For all purposes of this Seventieth Supplemental Indenture, except as
otherwise expressly provided or unless the context otherwise requires, the terms listed below,
when used with respect to the Bonds of the Seventy-second Series, shall have the meanings
specified below:
"Bond Purchase Agreement" means the Bond Purchase Agreement, dated May
14, 2026, relating to the Bonds of the Seventy-second Series, between the Company and
the purchasers listed on Schedule A thereto.
"Business Day" means any day, other than a Saturday or Sunday, which is not a
day on which banking institutions or trust companies in The City of New York, New
York are generally authorized or required by law, regulation or executive order to remain
closed.
"Initial Interest Accrual Date" means, with respect to any Bond of the Seventy-
second Series, the date from which interest on such Bond shall first accrue. The Initial
Interest Accrual Date of each Bond of such series shall be specified on the face of such
Bond.
17

"Institutional Investor" means (a) any original purchaser of a Bond of the
Seventy-second Series, (b) any holder of a Bond of the Seventy-second Series holding
(together with one or more of its affiliates) more than $1,000,000 in aggregate principal
amount of the Bonds of the Seventy-second Series, and (c) any bank, trust company,
savings and loan association or other financial institution, any pension plan, any
investment company, any insurance company, any broker or dealer, or any other similar
financial institution or entity, regardless of legal form.
"Interest Payment Date" means May 1 and November 1 in each year,
commencing November 1, 2026.
"Maturity" means the date on which the principal of the Bonds of the Seventy-
second Series becomes due and payable, whether at the Stated Maturity Date, upon
redemption or acceleration, or otherwise.
"Purchaser" means any purchaser listed on Schedule A to the related Bond
Purchase Agreement.
"Record Date", with respect to any Interest Payment Date, means the close of
business on the seventh Business Day preceding such Interest Payment Date.
"Stated Maturity Date" means May 1, 2056.
(V) Notwithstanding the provisions of Section 106 of the Original Mortgage,
as amended, the Company shall not cause any Bonds of the Seventy-second Series, or any
portion of the principal amount thereof, to be deemed to have been paid as provided in such
Section and its obligations in respect thereof to be deemed to be satisfied and discharged prior to
the Maturity thereof unless the Company shall deliver to the Trustee either:
(a) an instrument wherein the Company, notwithstanding the effect of
Section 106 of the Original Mortgage, as amended, in respect of such Bonds of the
Seventy-second Series, shall assume the obligation (which shall be absolute and
unconditional) to irrevocably deposit with the Trustee such additional sums of money, if
any, or additional government obligations (meeting the requirements of Section 106), if
any, or any combination thereof, at such time or times, as shall be necessary, together
with the money and/or government obligations theretofore so deposited, to pay when due
the principal of and premium, if any, and interest due and to become due on such Bonds
or portions thereof, all in accordance with and subject to the provisions of Section 106;
provided, however, that such instrument may state that the obligation of the Company to
make additional deposits as aforesaid shall be subject to the delivery to the Company by
the Trustee of a notice asserting the deficiency accompanied by an opinion of an
independent accountant showing the calculation thereof(which opinion shall be obtained
at the expense of the Company); or
(b) an Opinion of Counsel to the effect that the holders of such Bonds
of the Seventy-second Series, or portions of the principal amount thereof, will not
recognize income, gain or loss for United States federal income tax purposes as a result
of the satisfaction and discharge of the Company's indebtedness in respect thereof and
18

will be subject to United States federal income tax on the same amounts, at the same
times and in the same manner as if such satisfaction and discharge had not been effected.
(VI) Anything in this Seventieth Supplemental Indenture or the Bonds of the
Seventy-second Series to the contrary notwithstanding, any payment of principal of or premium,
if any, or interest on any Bond of the Seventy-second Series that is due on a date other than a
Business Day shall be made on the next succeeding Business Day without including the
additional days elapsed in the computation of the interest payable on such next succeeding
Business Day; provided, however, that if the Maturity date of any Bond of the Seventy-second
Series is a date other than a Business Day, the payment otherwise due at Maturity shall be made
on the next succeeding Business Day and shall include the additional days elapsed in the
computation of interest payable on such next succeeding Business Day.
(VII) The Bonds of the Seventy-second Series shall have such further terms as
are set forth in Exhibit E hereto. If there shall be a conflict between the terms of the form of
bond and the provisions of the Mortgage, the provisions of the Mortgage shall control to the
extent permitted by law.
ARTICLE III
Outstanding Bonds
Upon the delivery of this Seventieth Supplemental Indenture, Bonds of the
Seventy-first Series in an aggregate principal amount of$90,000,000 and Bonds of the Seventy-
second Series in an aggregate principal amount of$140,000,000 are authorized to be issued and
Outstanding, in addition to $3,163,700,000 aggregate principal amount of bonds of prior series
Outstanding at the date of delivery of this Seventieth Supplemental Indenture; it being
understood that, subject to the provisions of the Mortgage, there shall be no limit on the principal
amount of bonds that may be authenticated and delivered under the Mortgage.
ARTICLE IV
Prospective Amendments of Original Mortgage
SECTION 1. Each initial and subsequent holder of Bonds of the Seventy-first
Series and the Bonds of the Seventy-second Series, by virtue of its acquisition of an interest
therein, shall be deemed, without further act, to have consented to the amendments of the
Original Mortgage, as heretofore amended, contemplated in E(1), E(2) and E(3) to the Sixty-
sixth Supplemental Indenture, dated as of March 1, 2022.
ARTICLE V
Miscellaneous Provisions
SECTION 1. The terms defined in the Original Mortgage shall, for all purposes
of this Seventieth Supplemental Indenture, have the meanings specified in the Original
Mortgage.
19

SECTION 2. The Trustee hereby confirms its acceptance of the trusts in the
Original Mortgage declared, provided, created or supplemented and agrees to perform the same
upon the terms and conditions in the Original Mortgage set forth, including the following:
The Trustee shall not be responsible in any manner whatsoever for or in respect of
the validity or sufficiency of this Seventieth Supplemental Indenture or for or in respect of the
recitals contained herein, all of which recitals are made by the Company solely. Each and every
term and condition contained in Article XVI of the Original Mortgage shall apply to and form
part of this Seventieth Supplemental Indenture with the same force and effect as if the same were
herein set forth in full, with such omissions, variations and insertions, if any, as may be
appropriate to make the same conform to the provisions of this Seventieth Supplemental
Indenture.
SECTION 3. Whenever in this Seventieth Supplemental Indenture either of the
parties hereto is named or referred to, this shall, subject to the provisions of Articles XV and
XVI of the Original Mortgage be deemed to include the successors and assigns of such parry,
and all the covenants and agreements in this Seventieth Supplemental Indenture contained by or
on behalf of the Company, or by or on behalf of the Trustee, or either of them, shall, subject as
aforesaid, bind and inure to the respective benefits of the respective successors and assigns of
such parties, whether so expressed or not.
SECTION 4. Nothing in this Seventieth Supplemental Indenture, expressed or
implied, is intended, or shall be construed, to confer upon, or to give to, any person, firm or
corporation, other than the parties hereto and the holders of the bonds Outstanding under the
Mortgage, any right, remedy or claim under or by reason of this Seventieth Supplemental
Indenture or any covenant, condition, stipulation, promise or agreement hereof, and all the
covenants, conditions, stipulations, promises and agreements in this Seventieth Supplemental
Indenture contained by or on behalf of the Company shall be for the sole and exclusive benefit of
the parties hereto and the holders of the bonds Outstanding under the Mortgage.
SECTION 5. This Seventieth Supplemental Indenture shall be executed in
several counterparts, each of which shall be an original and all of which shall constitute but one
and the same instrument.
SECTION 6. The titles of the several Articles of this Seventieth Supplemental
Indenture shall not be deemed to be any part thereof.
20

IN WITNESS WHEREOF, on the IId' day of May, 2026, AVISTA
CORPORATION has caused its corporate name to be hereunto affixed, and this instrument to be
signed by its President or one of its Vice Presidents for and on its behalf, in The City of Spokane,
Washington, as of the day and year first above written, and on the 61' day of May, 2026,
CITIBANK, N.A., has caused its corporate name to be hereunto affixed, and this instrument to
be signed and sealed by its President or one of its Vice Presidents or one of its Senior Trust
Officers or one of its Trust Officers for and on its behalf, in The City of New York, New York,
all as of the day and year first above written.
AVISTA CORPORATION
By:
Nam : KevinJ. Christie
Title: Senior Vice President,
Chief Financial Officer, Treasurer and
Regulatory Affairs Officer
CITIBANK, N.A., as Trustee
By
Name: Eva Ling Waite
Title: Senior Trust Officer
21

IN WITNESS WHEREOF, on the I11h day of May, 2026, AVISTA
CORPORATION has caused its corporate name to be hereunto affixed, and this instrument to be
signed by its President or one of its Vice Presidents for and on its behalf, in The City of Spokane,
Washington, as of the day and year first above written, and on the 6th day of May, 2026,
CITIBANK, N.A., has caused its corporate name to be hereunto affixed, and this instrument to
be signed and sealed by its President or one of its Vice Presidents or one of its Senior Trust
Officers or one of its Trust Officers for and on its behalf, in The City of New York, New York,
all as of the day and year first above written.
AVISTA CORPORATION
By:
Name: Kevin J. Christie
Title: Senior Vice President,
Chief Financial Officer, Treasurer and
Regulatory Affairs Officer
CITIBANK,N as T s e
By
Name E a ing
Title: Senior Trust Officer
21

STATE OF WASHINGTON )
) ss..
COUNTY OF SPOKANE )
On this I Ph day of May, 2026, before me personally appeared Kevin J. Christie,
personally known to me to be a Senior Vice President, the Chief Financial Officer, the Treasurer
and the Regulatory Affairs Officer of AVISTA CORPORATION, one of the corporations that
executed the within and foregoing supplemental indenture, and acknowledged said instrument to
be the free and voluntary act and deed of said corporation, for the uses and purposes therein
mentioned, and on oath stated that he was authorized to execute said instrument.
IN WITNESS WHEREOF, I have hereunto set my hand and affixed my official
seal the day and year first above written.
Notary Public
NpTARy _
`•, - LESLIE M. KOEP
PUBLIC Notary Public
State of Washington
Commission Expires June 18, 2027
OF W
22

STATE OF NEW YORK )
) ss..
COUNTY OF SUFFOLK )
On this 61h day of May, 2026 before me, the undersigned, a Notary Public in and
for the State of New York, personally appeared Eva Ling Waite, personally known to me to be a
Senior Trust Officer of CITIBANK,N.A., whose name is subscribed to the within and foregoing
supplemental indenture, and acknowledged that she executed such instrument in her capacity as
such Senior Trust Officer and that, by her signature on such instrument, Citibank, N.A., as
trustee, on whose behalf said Eva Ling Waite acted, executed such instrument.
IN WITNESS WHEREOF, I have hereunto set my hand and affixed my official
seal the day and year first above written.
Notary Public --
PETER J. LOPEZ i
Notary Public State of New Yotk-•No 01 LO6117957 _
Qualified in Suffolk County _ t
Commission Expires November 1, &Z
23

EXHIBIT A
MORTGAGE, SUPPLEMENTAL INDENTURES
AND SERIES OF BONDS
MORTGAGE OR SERIES PRINCIPAL PRINCIPAL
SUPPLEMENTAL AMOUNT AMOUNT
INDENTURE DATED AS OF NO. DESIGNATION ISSUED OUTSTANDING
Original June 1, 1939 1 3-1/2%Series due 1964 $22,000,000 None
October 1, 1952 2 3-1/2%Series due 1982 30,000,000 None
1 (changed to 3-3/4%in
Twelfth Supplemental
Indenture)
2 May 1, 1953 3 3-7/8%Series due 1983 10,000,000 None
3 December 1, 1955 None
4 March 15, 1957 None
5 July 1, 1957 4 4-7/8%Series due 1987 30,000,000 None
6 January 1, 1958 5 4-1/8%Series due 1988 20,000,000 None
7 August 1, 1958 6 4-3/8%Series due 1988 15,000,000 None
8 January 1, 1959 7 4-3/4%Series due 1989 15,000,000 None
9 January 1, 1960 8 5-3/8%Series due 1990 10,000,000 None
10 April 1, 1964 9 4-5/8%Series due 1994 30,000,000 None
11 March 1 ,1965 10 4-5/8%Series due 1995 10,000,000 None
12 May 1, 1966 None
13 August 1, 1966 11 6%Series due 1996 20,000,000 None
14 April 1, 1970 12 9-1/4%Series due 2000 20,000,000 None
15 May 1, 1973 13 7-7/8%Series due 2003 20,000,000 None
16 February 1, 1975 14 9-3/8%Series due 2005 25,000,000 None
17 November 1, 1976 15 8-3/4%Series due 2006 30,000,000 None
18 June 1, 1980 None
19 January 1, 1981 16 14-1/8%Series due 1991 40,000,000 None
Subtotals $347,000,000 None
A-1

MORTGAGE OR SERIES PRINCIPAL PRINCIPAL
SUPPLEMENTAL AMOUNT AMOUNT
INDENTURE DATED AS OF NO. DESIGNATION ISSUED OUTSTANDING
August 1, 1982 17 15-3/4%Series due 1990- $60,000,000 None
20 1992
21 September 1, 1983 18 13-1/2%Series due 2013 60,000,000 None
22 March 1, 1984 19 13-1/4%Series due 1994 60,000,000 None
23 December 1, 1986 20 9-1/4%Series due 2016 80,000,000 None
24 January 1, 1988 21 10-3/8%Series due 2018 50,000,000 None
October 1, 1989 22 7-1/8%Series due 2013 66,700,000 None
25
23 7-2/5%Series due 2016 17,000,000 None
April 1, 1993 24 Secured Medium-Term 250,000,000 None
26 Notes,Series A
($250,000,000 authorized)
January 1, 1994 25 Secured Medium-Term 161,000,000 None
27 Notes,Series B
($250,000,000 authorized)
28 September 1,2001 26 Collateral Series due 2002 220,000,000 None
29 December 1,2001 27 7.75%Series due 2007 150,000,000 None
30 May 1,2002 28 Collateral Series due 2003 225,000,000 None
31 May 1,2003 29 Collateral Series due 2004 245,000,000 None
32 September 1,2003 30 6.125%Series due 2013 45,000,000 None
33 May 1,2004 31 Collateral Series due 2005 350,000,000 None
34 November 1,2004 32 5.45%Series due 2019 90,000,000 None
35 December 1,2004 33 Collateral Series 2004A 88,850,000 25,000,000
December 1,2004 34 Collateral Series 2004B 66,700,000 None
36
35 Collateral Series 2004C 17,000,000 None
37 December 1,2004 36 Collateral Series 2004D 350,000,000 None
May 1,2005 37 Collateral Series 2005B 66,700,000 None
38
38 Collateral Series 2005C 17,000,000 None
39 November 1,2005 39 6.25%Series due 2035 100,000,000 100,000,000
50,000,000 50,000,000
Subtotals $2,885,950,000 $175,000,000
A-2

MORTGAGE OR SERIES PRINCIPAL PRINCIPAL
SUPPLEMENTAL AMOUNT AMOUNT
INDENTURE DATED AS OF NO. DESIGNATION ISSUED OUTSTANDING
40 April 1,2006 40 Collateral Series due 2011 $320,000,000 None
41 December 1,2006 41 5.70%Series due 2037 150,000,000 150,000,000
42 April 1,2008 42 5.95%Series due 2018 250,000,000 None
43 November 1,2008 43 Collateral Series 2008A 200,000,000 None
44 December 1,2008 44 7.25%Series due 2013 30,000,000 None
45 December 1,2008 45 Collateral Series 2008B 17,000,000 None
46 September 1,2009 46 5.125%Series due 2022 250,000,000 None
47 November 1,2009 47 Collateral Series 2009A 75,000,000 None
December 1,2010 48 Collateral Series 2010A 66,700,000 66,700,000
48
49 Collateral Series 2010B 17,000,000 17,000,000
December 1,2010 50 3.89%Series due 2020 52,000,000 None
49
51 5.55%Series due 2040 35,000,000 35,000,000
50 December 1,2010 52 1.68%Series due 2013 50,000,000 None
51 February 1,2011 53 Collateral Series 2011A 400,000,000 None
52 August 1,2011 None
53 December 1,2011 54 4.45%Series due 2041 85,000,000 85,000,000
54 November 1,2012 55 4.23%Series due 2047 80,000,000 80,000,000
55 August 1,2013 56 Collateral Series 2013A 90,000,000 None
56 April 1,2014 57 Collateral Series 2014A 400,000,000 None
57 December 1,2014 58 4.11%Series due 2044 60,000,000 60,000,000
58 December 1,2015 59 4.37%Series due 2045 100,000,000 100,000,000
59 December 1,2016 60 3.54%Series due 2051 175,000,000 175,000,000
60 December 1,2017 61 3.91%Series due 2047 90,000,000 90,000,000
61 May 1,2018 62 4.35%Series due 2048 375,000,000 375,000,000
62 November 1,2019 63 3.43%Series due 2049 180,000,000 180,000,000
63 June 1,2020 64 Collateral Series 2020A 400,000,000 None
Subtotals $3,947,700,000 $1,413,700,000
A-3

MORTGAGE OR SERIES PRINCIPAL PRINCIPAL
SUPPLEMENTAL AMOUNT AMOUNT
INDENTURE DATED AS OF NO. DESIGNATION ISSUED OUTSTANDING
64 September 1,2020 65 3.07%Series due 2050 165,000,000 165,000,000
65 September 1,2021 66 2.90%Series due 2051 140,000,000 140,000,000
66 March 1,2022 67 4.00%Series due 2052 400,000,000 400,000,000
67 March 1,2023 68 5.66%Series due 2053 250,000,000 250,000,000
68 June 1,2023 69 Collateral Series 2023A 500,000,000 500,000,000
69 July 1,2025 70 6.18%Series due 2055 120,000,000 120,000,000
Subtotals$1,575,000,000 $1,575,000,000
Totals$8,755,650,000 $3,163,700,000
A-4

EXHIBIT B
FILING AND RECORDING OF
SIXTY-NINTH SUPPLEMENTAL INDENTURE
FILING IN STATE OFFICES
Financing Statement
State Office of Date Document Number
Washington Secretary of State 10/24/25 2025-297-5477-2
Idaho Secretary of State 10/24/25 20252067566
Montana Secretary of State 10/23/25 20250675758
Oregon Secretary of State 10/29/2025 94331414
RECORDING IN COUNTY OFFICES
Real Estate Mortgage Records Financing
Statement
Document Document
County Office of Date Number Book Page Number
Washington
Adams Auditor 8/1/25 339220 N/A N/A N/A
Asotin Auditor 8/8/25 387207 N/A N/A N/A
Benton Auditor 8/20/25 2025-019373 N/A N/A N/A
Douglas Auditor 8/4/25 3276905 N/A N/A N/A
Ferry Auditor 8/4/25 0302000 N/A N/A N/A
Franklin Auditor 8/18/25 2002453 N/A N/A N/A
Garfield Auditor 8/14/25 20250299 N/A N/A N/A
Grant Auditor 8/14/25 1515699 N/A N/A N/A
Klickitat Auditor 8/14/25 1169046 N/A N/A N/A
Lewis Auditor 8/14/25 3626497 N/A N/A N/A
Lincoln Auditor 9/15/25 2025-0501106 N/A N/A N/A
Pend Oreille Auditor 8/4/25 20250359393 N/A N/A N/A
Skamania Auditor 8/18/25 2025-001298 N/A N/A
Spokane Auditor 8/14/25 7434474 N/A N/A N/A
Stevens Auditor 8/1/25 2025-0004321 N/A N/A N/A
Thurston Auditor 9/17/25 5071721 N/A N/A N/A
Whitman Auditor 8/4/25 789169 N/A N/A N/A
Idaho
Benewah Recorder 8/4/25 305567 N/A N/A N/A
Bonner Recorder 8/1/25 1050198 N/A N/A N/A
Boundary Recorder 8/1/25 300571 N/A N/A N/A
Clearwater Recorder 8/4/25 250393 N/A N/A N/A
Idaho Recorder 8/4/25 550105 N/A N/A N/A
Kootenai Recorder 8/4/25 3011606000 N/A N/A N/A
Latah Recorder 8/4/25 641131 N/A N/A N/A
B-1

RECORDING IN COUNTY OFFICES
Real Estate Mortgage Records Financing
Statement
Document Document
County Office of Date Number Book Page Number
Idaho cont.
Lewis Recorder 8/4/25 153284 N/A N/A N/A
Nez Perce Recorder 8/14/25 923040 N/A N/A N/A
Shoshone Recorder 8/5/25 526047 N/A N/A N/A
Montana
Big Horn Clerk& Recorder 8/15/25 373073 207 50-90 N/A
Broadwater Clerk& Recorder 8/4/25 201927 272 857 N/A
Golden ValleV Clerk& Recorder 8/4/25 86142 M 23621 N/A
Meagher Clerk& Recorder 8/4/25 151518 N/A 1 of 42 N/A
Mineral Clerk& Recorder 8/18/25 131192
Rosebud Clerk& Recorder 8/15/25 0131347 174MG 895-936 N/A
Sanders Clerk& Recorder 8/15/25 337004 N/A
Stillwater Clerk& Recorder 8/4/25 396606 N/A N/A N/A
Treasure Clerk& Recorder 8/11/25 2025-0134 26 196 N/A
36061-
Wheatland Clerk& Recorder 8/4/25 113923 M 36101 N/A
Yellowstone Clerk& Recorder 8/12/25 4110815 N/A N/A N/A
Ore on
Douglas Recorder 8/14/25 2025-009211 N/A N/A N/A
Jackson Recorder 8/14/25 2025-017571 N/A N/A N/A
Josephine Recorder 8/14/25 2025-007459 N/A N/A N/A
Klamath Recorder 8/4/25 2025-006782 N/A N/A N/A
Morrow Recorder 8/14/25 2025-56890 N/A N/A N/A
Union Recorder 8/14/25 20251946 N/A N/A N/A
Wallowa Recorder 8/4/25 090994 N/A N/A N/A
B-2

EXHIBIT C
PROPERTY ADDITIONS
FIRST
THE ADDITIONAL ELECTRIC SUBSTATIONS AND SUBSTATION SITES of
the Company, including all buildings, structures, towers, poles, equipment, appliances and
devices for transforming, converting and distributing electric energy, and the lands of the
Company on which the same are situated and all of the Company's real estate and interests
therein, machinery, equipment, appliances, devices, appurtenances and supplies, franchises,
permits and other rights and other property forming a part of said substations or any of them, or
used or enjoyed or capable of being used or enjoyed in connection with any thereof, including,
but not limited to, the following situated in the State of Washington and the State of Idaho, to
wit:
State of Washington
Stevens County, State of Washington, "Aladdin Substation", granted by Chopot Lands, LLC, a
Washington limited liability company, conveys and warrants the following described real estate,
situated in the County of Stevens, State of Washington (the "Property"):
Abbreviated Legal: PTN SW 1/4, Section 3, Township 35 N, Range 39 E, W.M. Tax Parcel No.:
PTN2225800
That portion of the Southeast quarter, lying West of Aladdin County Road No. 9435 as located
on October 10, 1989, in Section 3, Township 35 North, Range 39 East, W.M., in Stevens
County, Washington, described as follows:
COMMENCING at a stone marking the Southeast corner of the Southwest quarter of said
Section 3, from which an aluminum cap marking the Southwest corner of said Section 3 bears
South 86°59'17" West a distance of 2680.77 feet; thence, along the South line of the Southwest
quarter of said Section 3, South 86'59'17"West a distance of 382.52 feet to the centerline of
Aladdin County Road and the TRUE POINT OF BEGINNING for this description; thence
Northeasterly along the centerline of said Aladdin County Road the following three (3) courses:
thence along the arc of a 1900.00 foot radius, non-tangent curve to the right, the chord of which
bears North 07°08'03"East a distance of 545.61 feet, through an interior angle of 16°30'37", for
an arc length of 547.50 feet; thence North 15°23'21" East a distance of 21.47 feet; thence along
the arc of a 1800.00 foot tangent curve to the right, the chord of which bears North 15°36'52"
East a distance of 14.15 feet, through an interior angle of 00°27'01" for an arc length of 14.15
feet, to the South line of that 20.00 foot wide access easement described in that document
recorded under Auditor's File Number 2012-0000624, said 20.00 foot wide easement being
centered on an existing gravel road; thence, leaving the centerline of said Aladdin Road and
along the South line of said 20.00 foot access easement the following four(4) courses: Thence
North 60°34'55"West a distance of 167.06 feet; thence Northwesterly along the arc of a 340.00
foot radius tangent curve to the left, the chord of which bears North 76°38'39"West a distance
of 188.14 feet, through an interior angle of 32°07'28" for an arc length of 190.63 feet; thence
South 87°17'37" West a distance of 72.21 feet; thence Westerly along the arc of a 290.00 foot
radius tangent curve to the right, the chord of which bears North 8738'l5' West a distance of
51.25 feet through an interior angle of 10°08'17" for an arc length of 51.31 feet; thence, leaving
C-1

the South line of said 20.00 foot access easement, South 10°10'37"West a distance of 738.12
feet to the South line of the Southwest quarter of said Section 3; thence, along said South line,
North 86°59'17"East a distance of 505.76 feet to the True Point of Beginning.
Designated as Amended Parcel A of that certain Certificate of Exemption No. COE 133-2025,
recorded November 24, 2025,under Auditor's File No. 2025-0006877.
Spokane County, State of Washington, "Waikiki Substation Expansion", granted by Ryan Oberg
and Amy Oberg, husband and wife, conveys and warrants the following described real estate,
situated in the County of Spokane, State of Washington:
THAT PORTION OF GOVERNMENT LOT 1 IN THE NORTHWEST QUARTER OF
SECTION 18, TOWNSHIP 26 NORTH, RANGE 43 EAST OF THE WILLAMETTE
MERIDIAN, MORE PARTICULARLY DESCRIBED AS FOLLOWS:
COMMENCING AT THE INTERSECTION OF THE NORTH LINE OF SAID
GOVERNMENT LOT 1 AND THE WEST RIGHT OF WAY LINE OF WAIKIKI ROAD;
THENCE WESTERLY ALONG SAID NORTH LINE OF GOVERNMENT LOT 1 A
DISTANCE OF 350 FEET TO THE POINT OF BEGINNING; THENCE EASTERLY ALONG
SAID NORTH LINE OF GOVERNMENT LOT 1, A DISTANCE OF 350 FEET TO THE
WESTERLY RIGHT OF WAY LINE OF SAID WAIKIKI ROAD; THENCE SOUTHERLY
ALONG SAID WESTERLY RIGHT OF WAY 352.73 FEET (354.62 FEET, RECORD);
THENCE CONTINUING SOUTHERLY ALONG SAID WESTERLY RIGHT OF WAY LINE
234.95 FEET (235.59, RECORD); THENCE NORTH 79°48'15" WEST ALONG THE
SOUTHERLY LINE OF WASHINGTON WATER POWER EASEMENT 350.00 FEET;
THENCE NORTHERLY TO THE POINT OF BEGINNING;
EXCEPT THAT PORTION LYING NORTHERLY OF A LINE DRAWN FROM A POINT ON
THE WESTERLY LINE OF THE ABOVE-DESCRIBED PROPERTY DISTANT
SOUTHERLY 287.37 FEET FROM THE NORTHWEST CORNER THEREOF TO A POINT
ON THE EASTERLY LINE OF THE ABOVE-DESCRIBED DISTANT SOUTHERLY 305.87
FEET FROM THE NORTHEAST CORNER THEREOF:
SITUATE IN THE COUNTY OF SPOKANE, STATE OF WASHINGTON.
Spokane County, State of Washington, "Waikiki Substation Expansion", granted by Harley C.
Douglass, Inc. a Washington corporation, conveys and warrants the following described real
estate, situated in the County of Spokane, State of Washington:
Parcel A:
That portion of Government Lot 1 of Section 18, Township 26 North, Range 43 East of the
Willamette Meridian, lying Northerly of centerline of vacated Burnett Road 101 and West of
Mills Street Road;
C-2

EXCEPT that portion described as follows:
Beginning at a point on the Northerly right of way line of 5 Mile Road, CPH No. 39, at
intersection with a line drawn parallel to and 424.86 feet Easterly, as measured at right angles
from the Westerly line of Government Lot 1; said point bearing North 81°55' East, 429.13 feet
from the Southwest corner of said Government Lot 1;
Thence North along said parallel line, a distance of 769.21 feet;
Thence South 80°33' East, 540 feet, more or less, to the Westerly right of way line of Waikiki
Road;
Thence along said right of way line Southerly to intersection with the centerline of Burnett Road
101, now vacated;
Thence along said centerline of Burnett Road Southwesterly to the Northerly right of way line of
5 Mile Road;
Thence along the right of way line Westerly to the Point of Beginning;
AND EXCEPT that portion described as follows:
Beginning at a point on the Northerly right of way line of said CPH No. 39, at its intersection
with a line drawn parallel to and 424.86 feet Easterly, as measured at right angles from the
Westerly line of Government Lot 1, said point bearing North 81°55' East, 429.13 feet from the
Southwest corner of said Government Lot 1;
Thence North along said parallel line, a distance of 446.78 feet;
Thence North 81'32' West, 197.15 feet;
Thence South 446.78 feet, more or less, to a point on the Northerly right of way line of said CPH
No. 39;
Thence Southeasterly along the Northerly right of way line of said road, to the Point of
Beginning;
AND EXCEPT that portion described as follows:
Commencing at the intersection of the North line of said Government Lot 1 and the West right of
way line of Waikiki Road;
Thence West along the North line of said Government Lot 1, 350 feet to the True Point of
Beginning;
Thence East along said North line of Government Lot 1, 350 feet to the West right of way line of
said Waikiki Road;
Thence South 1°55'30"East along said West right of way line 354.62 feet;
C-3

Thence South 1°34'20" East, 235.59 feet to a point on the Southerly line of the Washington
Water Power Company Transmission Line right of way;
Thence North 79°48'15" West, (North 80°33' West record) along said Southerly right of way
line 350 feet;
Thence North 1°55'30"West to the Point of Beginning;
EXCEPT that portion lying Northerly of a line drawn from a point 287.37 feet South of the
Northwest corner, as measured along the West line thereof, to a point 305.87 feet South of the
Northeast corner as measured along the East line thereof,
AND ALSO EXCEPT that portion lying Southerly of the Northerly line of Five Mile Road;
In Spokane County Washington.
Parcel B:
That portion of the Northeast Quarter of the Northeast Quarter of Section 13, Township 26
North, Range 42 East of the Willamette Meridian, lying North of Five Mile Road, EXCEPT that
portion described as follows:
Beginning at a point 174.3 feet South of the Northeast corner;
Thence South 346 feet;
Thence North 79°42' West, 312.6 feet;
Thence North 10'18' East, 313.7 feet;
Thence South 85°52' East, 256.1 feet to the Point of Beginning;
AND EXCEPT that portion described as follows:
Beginning at the intersection of the North line of Five Mile Road and the West line of said
Northeast Quarter of the Northeast Quarter;
Thence North to the South line of Grand Coulee Transmission Line No. I Easement;
Thence East along said South line, a distance of 435.82 feet;
Thence North 46°28' East, 167.53 feet;
Thence North 89°31' East, 50 feet;
Thence South 0° 29' East, 248.58 feet, more or less,to the North line of Five Mile Road;
Thence Southwesterly along said road to the Point of Beginning;
In Spokane County, Washington.
C-4

State of Idaho
Nez Perce County, State of Idaho, "Powers 115kV Substation", granted by Norton Investments,
LLC, an Idaho limited liability company, Larry R. Norton and Jennifer A.Norton, husband and
wife, Gregory S. Norton, Sr., as the trustee of the Survivor's Trust and the Bypass Trust of
Norton Revocable Living Trust uad August 29, 1989, and Viola Gay Norton, a widow, conveys
and warrants the following real property located in the County of Nez Perce, State of Idaho, to-
wit:
Parcel 1:
That portion of a parcel described in Personal Representative's Deed, Instrument#914422,Nez
Perce County Records, located within the South 330 feet of Lots 5,6,7, and 8 of Block 39 of
Lewiston Orchards Tract No. 3 to the City of Lewiston, according to the recorded plat thereof,
records of Nez Perce County, Idaho, measurements being from the centerlines of adjacent streets
and alleys, more particularly described as follows:
Commencing at the southeast corner of Section 17, Township 35 North, Range 5 West, Boise
Meridian, also being the intersection of 1 Oth Street and Powers Avenue, thence along the
centerline of loth Street,N00°27'31"E, 295.18 feet, thence leaving said centerline,
S86042'35'W, 30.06 feet to a point on the west right-of-way loth Street, and the Point of
Beginning:
Thence continuing S86042'35"W, 661.11 feet;
Thence S54°57'47"W, 347.64 feet, to a point on the north right-of-way of Powers Avenue;
Thence along said right-of-way,N88028'25"W, 371.93 feet, to the intersection of the North
right-of-way of Powers Avenue and the east right-of-way of 9th Street;
Thence along said east right-of-way,NO1°O1'54"E, 210.23 feet, to the southwest corner of a
parcel described in Warranty Deed, Instrument#742977,Nez Perce County Records; Thence
along the south line of said parcel the following two (2) courses:
N48046'39"E, 132.27 feet;
Thence 588°29'21"E, 549.33 feet, to the southwest corner of a parcel described in Real Property
Deed to Trust, Instrument#619976,Nez Perce County Records;
Thence along the south line of said parcel, S88°28'13"E, 336.64 feet, to the southwest corner of
Tract A of Canyon Shadows No. 2 Block 1 Subdivision; Thence along the south line of said
tract, S88°14'52"E, 7.98 feet, to the southwest corner of Lot 1 of said subdivision;
Thence along the south line of said lot, S88°26'49"E, 319.96 feet, to a point on the west right-of-
way of 1 Oth Street;
Thence along said right-of-way, S00°27'31"W, 3 7.3 5 feet, to the Point of Beginning.
Parcel 2:
That portion of a parcel described in Personal Representative's Deed, Instrument#914422,Nez
Perce County Records, located within the South 330 feet of Lots 5,6,7, and 8 of Block 39 of
Lewiston Orchards Tract No. 3 to the City of Lewiston, according to the recorded plat thereof,
records of Nez Perce County, Idaho, measurements being from the centerlines of adjacent streets
and alleys, more particularly described as follows:
C-5

Commencing at the southeast corner of Section 17, Township 35 North, Range 5 West, Boise
Meridian, also being the intersection of loth Street and Powers Avenue, thence along the
centerline of 1Oth Street,N00°27'31"E, 30.00 feet, thence leaving said centerline,N88°28'25"W,
30.00 feet to the intersection of the west right-of-way of 1 Oth Street, and the north right-of-way of
Powers Avenue, also the Point of Beginning:
Thence continuing along said north right-of-way,N88°28'25"W, 942.89 feet;
Thence leaving said right-of-way,N54°57'47"E, 347.64 feet;
Thence N86°42'35"E, 661.11 feet, to a point on the west right-of-way of loth Street;
Thence along said right-of-way, S00°27'31"W, 262.65 feet, to the Point of Beginning.
Nez Perce County, State of Idaho, `Bryden Canyon Substation", granted by William Virgil
Schara and Jodell Schara Allinger, dealing with their separate property and Craig T. Clifford,
Trustee of the Clifford Family Intervivos Trust, dated June 13, 1991, the following described
premises in Nez Perce County, Idaho, TO WIT:
From the monument marking the intersection of the South line of University Second Addition to
the City of Lewiston, Idaho with the North-South Quarter line of Section 1, Township 35 North,
Range 6, West of the Boise Meridian, having a city reference no. 5/66; thence South 0°03' East a
distance of 381.2 feet to a point on the center line of Southway, said point being the true place of
beginning; thence South 82°54' West a distance of 276.2 feet along Southway; thence South
4°27' West a distance of 1050.9 feet; thence North 7738' West a distance of 223.8 feet; thence
North 28°38' West a distance of 133.3 feet; thence South 8738' West a distance of 182.1 feet to
a point on the center line of Country Club Road; thence South 8°37' East a distance of 183.85
feet along Country Club Road; thence continuing along said Country Club Road South 3°21'
East a distance of 142.6 feet; thence South 89°58' East a distance of 785.3 feet to a point; thence
North 0°03' West a distance of 1249.2 feet to the true place of beginning. EXCEPTING from the
above described tract all that portion lying within the legal boundaries of public roads.
AND
From the monument marking the intersection of the South line of University Second Addition to
the City of Lewiston, Idaho, with the North-South Quarter line of Section 1, Township 35 North,
Range 6, West of the Boise Meridian, having a city reference no. 5/66; thence South 0°03' East a
distance of 381.2 feet to a point on the center line of Southway; thence South 82°54' West a
distance of 276.2 feet, said point being the true place of beginning; thence South 4°27' West a
distance of 1050.9 feet; thence North 77°38' West a distance of 51.5 feet; thence North 4°27'
East a distance of 1033.4 feet; thence North 82°54' East a distance of 52.05 feet to the true place
of beginning. EXCEPTING from the above described tract all that portion lying within the legal
boundaries of public roads.
EXCEPTING,
Commencing at the monument marking the intersection of the South line of University Second
Addition to the City of Lewiston,Nez Perce County, State of Idaho, with the North-South
Quarter line of Section 1, Township 35 North, Range 6 West of the Boise Meridian, having a city
reference No. 5/66; thence South 0°03' East for a distance of 1249.2 feet; thence North 89°58'
C-6

West for a distance of 356.84 feet to the true place of beginning; thence continue North 89°58'
West for a distance of 428.46 feet to Snake River Avenue; thence North 3°21' West along Snake
River Avenue for a distance of 142.6 feet; thence North 8°37' West along Snake River Avenue
for a distance of 183.85 feet; thence North 87°38' East for a distance of 182.1 feet; thence South
28°38' East for a distance of 133.3 feet; thence South 77°38' East for a distance of 223.8 feet;
thence South 0°02' West for a distance of 166.97 feet to the true place of beginning. All being a
part of Government Lot 1, Section 12, Township 35 North, Range 6 West of the Boise Meridian,
Nez Perce County, Idaho. EXCEPTING from the above described tract all that portion lying
within the legal boundaries of public roads.
ALSO EXCEPTING,
Commencing at the monument marking the intersection of the South line of University Second
Addition to the City of Lewiston,Nez Perce County, State of Idaho, with the North-South
Quarter line of Section 1, Township 35 North, Range 6 West of the Boise Meridian, having a
City reference of No. 5/66; thence South 0°03' East for a distance of 381.2 feet to a point on the
centerline of Southway; thence continue South 0°03' East for a distance of 887.97 feet to the
True Place of Beginning; thence continue South 0°03' East for a distance of 361.23 feet; thence
North 89°58' West for a distance of 356.84 feet; thence North 0°02' East for a distance of 166.97
feet; thence North 4°27' East for a distance of 194.33 feet; thence North 89°57' East for a
distance of 341.35 feet to the True Place of Beginning. All being a part of Government Lot 1,
Section 12, Township 35 North, Range 6 West of the Boise Meridian,Nez Perce County, Idaho.
ALSO EXCEPTING,
That part of the Southwest Quarter of Section 1, Township 35 North, Range 6 West of the Boise
Meridian and in part of Government 5 of Section 12, Township 35 North, Range 6 West of the
Boise Meridian,Nez Perce County, described as follows:
Commencing at the monument marking the intersection of the South line of University Second
Addition to the City of Lewiston,Nez Perce County, Idaho with the North-South Quarter line of
Section 1, Township 35 North, Range 6 West of the Boise Meridian, having a City Reference
Number of 5/66; thence South 00°03'00" East, a distance of 381.20 feet to a point on the
centerline of Southway Avenue; thence South 82°54'00" West, along Southway Avenue a
distance of 328.25 feet to the True Point of Beginning; thence continue South 82°54'00" West, a
distance of 95.25 feet to a concrete monument; thence South 12°03'00" West, a distance of 42.60
feet; thence South 34°58'00" West, along Snake River Avenue, a distance of 494.40 feet; thence
continuing along Snake River Avenue, South 20°33'00"West, a distance of 275.50 feet; thence
continue along Snake River Avenue, South 5°38'00" West, a distance of 11.99 feet; thence East,
a distance of 307.26 feet; thence South, a distance of 156.92 feet; thence North 89°55'39" East, a
distance of 159.52 feet; thence North 4°27'00" East, a distance of 383.67 feet; thence North
85°33'00" West, a distance of 51.03 feet; thence North 4°27'00" East, a distance of 500.00 feet
to the True Point of Beginning.
ALSO EXCEPTING,
A parcel of land being on both sides of the centerline of the Southway 8th Street to Snake River
Avenue Pathway of said Project No. STP-7224 (100) as shown on the plans therof now on file in
the office of the Idaho Transportation Department, Division of Highways, and being a portion of
C-7

Section 1, Township 35 North, Range 6 West, Boise Meridian,Nez Perce County, Idaho,
described as follows, to wit:
Commencing at the Northwest corner of the Southwest Quarter of the Southeast Quarter of
Section 1, Township 35 North, Range 6 West, Boise Meridian, having a City of Lewiston
reference No. 5/66; thence South 89°53'10" East a distance of 80.689 meters (264.73 feet) to the
monument marking the intersection of 1 st Street& 19th Avenue, having a City of Lewiston
reference No. 5/66; thence South 00°03'00" East a distance of 121.270 meters (397.87 feet) to a
point on a curve on the proposed centerline coincident with Station 12+67.366 of said Project
No. STP-7224 (100); thence Southwesterly along said curve being a 295.000 meter(967.85 foot)
radius curve right— 11.339 meters (37.20 feet), with a chord length of 11.338 meters (37.20 feet)
which bears South 82°10'49" West to a point being coincident with Station 12+56.027 of said
centerline; thence South 83°16'53" West—71.716 meters (235.29 feet) along said proposed
centerline to a point being coincident with Station 11+84.311 of said centerline; thence South
06°43'07" East-13.073 meters (42.89 feet) to the westerly right-of-way of 1st Street to a point,
which bears South 06°43'07" East 13.073 meters (42.89 feet) from Station 11+84.311 of said
centerline of the Southway Bicycle &Pedestrian Path Survey, and being the Real Point of
Beginning.
ALSO EXCEPTING,
That part of the Southwest Quarter of Section 1, Township 35 North, Range 6 West of the Boise
Meridian, and part of Government Lot 5, Section 12, Township 35 North, Range 6 West of the
Boise Meridian,Nez Perce County, Idaho, described as follows:
Commencing at the monument marking the intersection of the South line of University Second
Addition to the City of Lewiston,Nez Perce County, Idaho with the North-South Quarter line of
Section 1, Township 35 North, Range 6 West of the Boise Meridian, having a City Reference
Number of 5/66; thence South 00°03'00" East, a distance of 381.20 feet to a point on the
centerline of Southway Avenue; thence South 82°54'00" West, along Southway Avenue, a
distance of 328.25 feet; thence continue South 82°54'00" West, a distance of 95.25 feet to a
concrete monument; thence South 12°03'00" West, a distance pf 42.60 feet; thence South
34°58'00" West, along Snake River Avenue, a distance of 494.10 feet; thence continuing along
Snake River Avenue, South 20°33'00" West, a distance of 275.50 feet; thence South 5°38'00"
West, a distance of 146.15 feet; thence South 8°37'00" East, a distance of 22.40 feet; thence
North 8738'00" East, a distance of 182.100 feet; thence South 28°38'00" East, a distance of
133.30 feet to the True Point of Beginning; thence North 33°21'45" East, a distance of 129.56
feet; thence North 77°38'00" West, a distance of 223.80 feet to the True Point of Beginning.
Second
ADDITIONAL PROTECTION, MITIGATION AND ENHANCEMENT
PROPERTY of the Company,real, personal, or mixed, acquired, constructed and/or installed in,
on, under and/or proximate to the Company's hydroelectric generation developments for the
purpose of protecting and/or enhancing wildlife (including fish and aquatic life), botanical life
and/or wetlands, and/or mitigating any harm or damage thereto, and all other property, real,
personal or mixed, used or enjoyed or capable of being used or enjoyed in conjunction therewith,
including,but not limited to, the following in the State of Washington to wit:
C-8

Situate in the County of Stevens, State of Washington, "Kettle Falls Ash Landfill Buffer
Property Expansion granted by Boise Cascade Wood Products, L.L.C., a Delaware limited
liability company, fka Boise Building Solutions Manufacturing, L.L.C., conveys and warrants
the following described real estate, situated in the County of Stevens, State of Washington:
Government Lot 3 of Section 19, Township 36 North, Range 38 East, W.M., in Stevens County,
Washington.
Excepting therefrom a strip of land 100 feet in width across said property, conveyed by Arthur
W. Schenk, a bachelor, to the United States, by deed dated August 30, 1941, recorded in Book
111 of Deeds, Page 96.
Together with a perpetual easement 60 feet in width for ingress, egress, and utilities over existing
roads or roads to be constructed on mutually agreeable locations over and across that portion of
Grantor's property legally described as that part of Government Lots 1 and 2 of Section 19,
Township 36 North, Range 38 East, of the Willamette Meridian, Stevens County, Washington,
lying South of Primary State Highway No. 3; Except that portion within railroad right of way;
Except all that portion of Government Lots 1 and 2 (W1/2 of the NW1/4) of Section 19,
Township 36 North, Range 38 E.W.M., lying Southwesterly of existing State Route No. 395 and
lying Northeasterly of a line drawn parallel with and 70 feet Southwesterly, when measured at
right angles and/or radially, from the centerline of SR 395, Kettle Falls to Kettle Falls Bridge and
extending Northwesterly from Highway Engineers Station C.S. 84+66.1 to the West boundary
line of said Government Lot 2 (SW 1/4 of the NW 1/4) of Section 19. All in Stevens County,
Washington.
Parcel No.: 1919400
Third
BUSINESS OFFICE(S) AND/OR MISCELLANEOUS REAL ESTATE, in the State
of Washington, to wit:
Situate in the County of Adams, State of Washington, "Ritzville Service Center", granted by
Watson EWA, LLC, a Washington Limited Liability Company and Globe, LLC, a Washington
Limited Liability Company and McCall, LLC, a Washington Limited Liability Company,
conveys and warrants the following described real estate, situated in the County of Adams, State
of Washington:
Lots 1-5 inclusive, Block 4, Ritzville Realty Co's Division Addition to Ritzville, according to the
Plat thereof of record in the office of the Auditor, Adams County, WA., together with the
Northeasterly 30 ft. of vacated Stevens Street adjoining and abutting to Lot 5, and together with
that portion of vacated Whitman St. adjoining and abutting to Lot 1.
C-9

EXHIBIT D
(Form of Bond)
PPN: 05379B F*3
AVISTA CORPORATION
First Mortgage Bond, 4.77% Series due 2029
REGISTERED REGISTERED
NO. $
AVISTA CORPORATION, a corporation of the State of Washington
(hereinafter called the "Company"), for value received, hereby promises to pay to
or registered assigns, on May 1,2029 (the "Stated Maturity Date")
DOLLARS
and to pay the registered owner hereof interest thereon semi-annually in arrears on May I and
November I in each year (each such date, an "Interest Payment Date"), commencing November 1,
2026, and at Maturity (as hereinafter defined), at the rate of four and seventy-seven one-
hundredths per centum(4.77%)per annum computed on the basis of a 360-day year consisting of
twelve 30-day months, until the Company's obligation with respect to the payment of such
principal shall have been discharged. This bond shall bear interest from May 14, 2026 or from
the most recent Interest Payment Date on or prior to the date of this bond to which interest on the
bonds of this series has been paid.
Dated: AVISTA CORPORATION
By:
Name:
Title:
ATTEST:
Name:
Title:
TRUSTEE'S CERTIFICATE
This bond is one of the bonds of the series herein designated, described or
provided for in the within-mentioned Mortgage.
CITIBANK,N.A.
Trustee
By
Authorized Signatory
D-1

The principal of and premium, if any, and interest on this bond payable at
Maturity shall be payable to the registered owner hereof upon presentation hereof at the office or
agency of the Company in the Borough of Manhattan, The City of New York, in such coin or
currency of the United States of America as at the time of payment is legal tender for public and
private debts. The interest on this bond (other than interest payable at Maturity) shall be paid by
check, in the similar coin or currency, mailed to the registered owner hereof as of the close of
business on the seventh Business Day (as defined in the Seventieth Supplemental Indenture
referred to below) preceding each Interest Payment Date (each such date being herein called a
"Record Date"); provided, however, that if such registered owner shall be a securities depositary,
such payment shall be made by such other means in lieu of check as shall be agreed upon by the
Company, the Trustee and such registered owner; and provided further that, so long as this Bond
shall be held by (a) the original purchaser hereof under the Bond Purchase Agreement (as
defined in such Seventieth Supplemental Indenture) or (b) any other Institutional Investor (as
defined in such Supplemental Indenture) that (i) is the direct or indirect transferee of this bond
from such original purchaser and (ii) has made the same agreement relating to this bond as such
original purchaser made in Section 8.2 of the Bond Purchase Agreement, payment of principal of
and premium, if any, and interest on this Bond shall be payable in the manner specified in the
Bond Purchase Agreement. Interest payable at Maturity shall be paid to the person to whom
principal shall be paid. As used herein, the term "Maturity" shall mean the date on which the
principal of this bond becomes due and payable, whether at stated maturity, upon redemption or
acceleration, or otherwise.
This bond is one of an issue of bonds of the Company issuable in series and is one
of a series known as its First Mortgage Bonds, 4.77% Series due 2029, all bonds of all such
series being issued and issuable under and equally secured (except insofar as any sinking or other
fund, established in accordance with the provisions of the Mortgage hereinafter mentioned, may
afford additional security for the bonds of any particular series) by a Mortgage and Deed of
Trust, dated as of June 1, 1939 (the "Original Mortgage"), executed by the Company (formerly
known as The Washington Water Power Company) to City Bank Farmers Trust Company and
Ralph E. Morton, as Trustees (Citibank, N.A., successor Trustee to both said Trustees). The
Original Mortgage has been amended and supplemented by various supplemental indentures,
including the Seventieth Supplemental Indenture, dated as of May 1, 2026 (the "Seventieth
Supplemental Indenture"), and, as so amended and supplemented, is herein called the
"Mortgage". Reference is made to the Mortgage for a description of the property mortgaged and
pledged, the nature and extent of the security, the rights of the holders of the bonds and of the
Trustee in respect thereof, the duties and immunities of the Trustee, the terms and conditions
upon which the bonds are and are to be secured and the circumstances under which additional
bonds may be issued. If there shall be a conflict between the terms of this bond and the
provisions of the Mortgage, the provisions of the Mortgage shall control to the extent permitted
by law. The holder of this bond, by its acceptance hereof, shall be deemed to have consented
and agreed to all of the terms and provisions of the Mortgage and, further, in the event that such
holder shall not be the sole beneficial owner of this bond, shall be deemed to have agreed to use
all commercially reasonable efforts to cause all direct and indirect beneficial owners of this bond
to have knowledge of the terms and provisions of the Mortgage and of this bond and to comply
therewith, including particularly, but without limitation, any provisions or restrictions in the
Mortgage regarding the transfer or exchange of such beneficial interests and any legend set forth
on this bond.
D-2

The Mortgage may be modified or altered by affirmative vote of the holders of at
least 60% in principal amount of the bonds outstanding under the Mortgage, considered as one
class, or, if the rights of one or more, but less than all, series of bonds then outstanding are to be
affected, then such modification or alteration may be effected with the affirmative vote only of
60% in principal amount of the bonds outstanding of the series so to be affected, considered as
one class, and, furthermore, for limited purposes, the Mortgage may be modified or altered
without any consent or other action of holders of any series of bonds. No modification or
alteration shall, however, permit an extension of the Maturity of the principal of, or interest on,
this bond or a reduction in such principal or the rate of interest hereon or any other modification
in the terms of payment of such principal or interest or the creation of any lien equal or prior to
the lien of the Mortgage or deprive the holder of a lien on the mortgaged and pledged property
without the consent of the holder hereof. Each initial and subsequent holder of bonds of this
series, by virtue of its acquisition of an interest therein, shall be deemed, without further act, to
have consented to the prospective amendments to the Original Mortgage set forth or referred to
in the Seventieth Supplemental Indenture.
The principal hereof, together with all accrued and unpaid interest hereon (but
without premium), may be declared or may become due prior to the Stated Maturity Date on the
conditions, in the manner and at the time set forth in the Mortgage, upon the occurrence of a
Completed Default as in the Mortgage provided.
As provided in the Mortgage and subject to certain limitations therein set forth,
this bond or any portion of the principal amount hereof will be deemed to have been paid if there
has been irrevocably deposited with the Trustee moneys or direct obligations of or obligations
guaranteed by the United States of America, the principal of and interest on which when due, and
without regard to any reinvestment thereof, will provide moneys which, together with moneys so
deposited, will be sufficient to pay when due the principal of and premium, if any, and interest
on this bond when due.
The Mortgage contains terms, provisions and conditions relating to the
consolidation or merger of the Company with or into, and the conveyance or other transfer, or
lease, of assets to, another corporation and to the assumption by such other corporation, in certain
circumstances, of all of the obligations of the Company under the Mortgage and on the bonds
secured thereby.
In the manner prescribed in the Mortgage, this bond is transferable by the
registered owner hereof in person, or by his duly authorized attorney, at the office or agency of
the Company in the Borough of Manhattan, The City of New York, upon surrender and
cancellation of this bond, together with a written instrument of transfer whenever required by the
Company duly executed by the registered owner or by its duly authorized attorney, and,
thereupon, a new fully registered bond of the same series for a like principal amount will be
issued to the transferee in exchange herefor as provided in the Mortgage. The Company and the
Trustee may deem and treat the person in whose name this bond is registered as the absolute
owner hereof for the purpose of receiving payment and for all other purposes.
In the manner prescribed in the Mortgage, any bonds of this series, upon
surrender thereof for cancellation at the office or agency of the Company in the Borough of
D-3

Manhattan, The City of New York, are exchangeable for a like aggregate principal amount of
bonds of the same series of other authorized denominations.
Prior to the Par Call Date (as hereinafter defined), the bonds of this series shall be
redeemable in whole at any time or in part from time to time, at the option of the Company, upon
notice mailed as provided in Section 52 of the Mortgage, at a redemption price equal to the
greater of
(a) 100% of the principal amount of the bonds being redeemed and
(b) (i) the sum of the present values of the remaining scheduled payments
of principal of and interest on the bonds being redeemed (assuming, for this purpose, that
the bonds of this series were stated to mature on the Par Call Date), discounted to the date
of redemption on a semiannual basis (assuming a 360-day year consisting of twelve 30-
day months) at a discount rate equal to the Treasury Yield(as hereinafter defined)plus 50
basis points, less (ii) interest accrued to the redemption date,
plus, in the case of either (a) or (b) above, whichever is applicable, accrued and unpaid interest
on such bonds to the date of redemption.
On or after the Par Call Date, the bonds of this series shall be redeemable in
whole at any time, or in part from time to time, at the option of the Company,upon notice mailed
as aforesaid, at a redemption price equal to 100% of the principal amount of the bonds being
redeemed plus accrued and unpaid interest on such bonds to the date of redemption.
"Par Call Date" means April 1, 2029.
"Treasury Yield" has the meaning set forth in the Seventieth Supplemental
Indenture.
If the Company shall have reasonably determined that it is reasonably likely that
any Purchaser (as defined in the Bond Purchase Agreement) is a "specified foreign entity" (as
defined in Section 7701(a)(51)(B) of the Internal Revenue Code of 1986, as amended), then the
bonds of this series held by such Purchaser shall be redeemable in whole at any time, or in part
from time to time, at the option of the Company, at a redemption price of 100% of the principal
amount of the bonds to be redeemed plus accrued and unpaid interest to the date of redemption.
If there shall be more than one such Purchaser, the Company shall determine the Purchaser or
Purchasers whose bonds of this series are to be redeemed in accordance with this paragraph and
the principal amount of bonds of each such Purchaser to be redeemed.
Except as provided above, (a)the bonds of this series are not redeemable prior to
the Stated Maturity Date and (b) no amount other than the principal of and interest on the bonds
of this series shall be payable in respect of such bonds at Maturity or otherwise.
No recourse shall be had for the payment of the principal of or premium, if any, or
interest on this bond against any incorporator or any past, present or future subscriber to the
capital stock, stockholder, officer or director of the Company or of any predecessor or successor
corporation, as such, either directly or through the Company or any predecessor or successor
D-4

corporation, under any rule of law, statute or constitution or by the enforcement of any
assessment or otherwise, all such liability of incorporators, subscribers, stockholders, officers
and directors being released by the holder or owner hereof by the acceptance of this bond and
being likewise waived and released by the terms of the Mortgage.
This bond shall not become obligatory until Citibank, N.A., the Trustee under the
Mortgage, or its successor thereunder, shall have signed the form of certificate endorsed hereon.
D-5

ASSIGNMENT FORM
FOR VALUE RECEIVED the undersigned hereby sells, assigns and transfers unto
[please insert social security or other identifying number of assignee]
[please print or typewrite name and address of assignee]
the within bond of AVISTA CORPORATION and does hereby irrevocably constitute and
appoint , Attorney, to transfer said bond
on the books of the within-mentioned Company, with full power of substitution in the premises.
Dated:
[signature of assignor]
Notice: The signature to this assignment must correspond with the name as written upon the face
of the bond in every particular without alteration or enlargement or any change whatsoever.
D-6

EXHIBIT E
(Form of Bond)
PPN: 05379B F@1
AVISTA CORPORATION
First Mortgage Bond, 6.10% Series due 2056
REGISTERED REGISTERED
NO. $
AVISTA CORPORATION, a corporation of the State of Washington
(hereinafter called the "Company"), for value received, hereby promises to pay to
or registered assigns, on May 1,2056 (the "Stated Maturity Date")
DOLLARS
and to pay the registered owner hereof interest thereon semi-annually in arrears on May 1 and
November 1 in each year (each such date, an "Interest Payment Date"), commencing November 1,
2026, and at Maturity (as hereinafter defined), at the rate of six and ten one-hundredths per
centum (6.10%)per annum computed on the basis of a 360-day year consisting of twelve 30-day
months, until the Company's obligation with respect to the payment of such principal shall have
been discharged. This bond shall bear interest from
(the "Initial Interest Accrual Date") or from the most recent Interest Payment Date on or prior to
the date of this bond to which interest on the bonds of this series has been paid.
Dated: AVISTA CORPORATION
By:
Name:
Title:
ATTEST:
Name:
Title:
TRUSTEE'S CERTIFICATE
This bond is one of the bonds of the series herein designated, described or
provided for in the within-mentioned Mortgage.
CITIBANK,N.A.
Trustee
By
Authorized Signatory
E-1

The principal of and premium, if any, and interest on this bond payable at
Maturity shall be payable to the registered owner hereof upon presentation hereof at the office or
agency of the Company in the Borough of Manhattan, The City of New York, in such coin or
currency of the United States of America as at the time of payment is legal tender for public and
private debts. The interest on this bond (other than interest payable at Maturity) shall be paid by
check, in the similar coin or currency, mailed to the registered owner hereof as of the close of
business on the seventh Business Day (as defined in the Seventieth Supplemental Indenture
referred to below) preceding each Interest Payment Date (each such date being herein called a
"Record Date"); provided, however, that if such registered owner shall be a securities depositary,
such payment shall be made by such other means in lieu of check as shall be agreed upon by the
Company, the Trustee and such registered owner; and provided further that, so long as this Bond
shall be held by (a) the original purchaser hereof under the Bond Purchase Agreement (as
defined in such Seventieth Supplemental Indenture) or (b) any other Institutional Investor (as
defined in such Supplemental Indenture) that (i) is the direct or indirect transferee of this bond
from such original purchaser and (ii) has made the same agreement relating to this bond as such
original purchaser made in Section 8.2 of the Bond Purchase Agreement, payment of principal of
and premium, if any, and interest on this Bond shall be payable in the manner specified in the
Bond Purchase Agreement. Interest payable at Maturity shall be paid to the person to whom
principal shall be paid. As used herein, the term "Maturity" shall mean the date on which the
principal of this bond becomes due and payable, whether at stated maturity, upon redemption or
acceleration, or otherwise.
This bond is one of an issue of bonds of the Company issuable in series and is one
of a series known as its First Mortgage Bonds, 6.10% Series due 2056, all bonds of all such
series being issued and issuable under and equally secured (except insofar as any sinking or other
fund, established in accordance with the provisions of the Mortgage hereinafter mentioned, may
afford additional security for the bonds of any particular series) by a Mortgage and Deed of
Trust, dated as of June 1, 1939 (the "Original Mortgage"), executed by the Company (formerly
known as The Washington Water Power Company) to City Bank Farmers Trust Company and
Ralph E. Morton, as Trustees (Citibank, N.A., successor Trustee to both said Trustees). The
Original Mortgage has been amended and supplemented by various supplemental indentures,
including the Seventieth Supplemental Indenture, dated as of May 1, 2026 (the "Seventieth
Supplemental Indenture"), and, as so amended and supplemented, is herein called the
"Mortgage". Reference is made to the Mortgage for a description of the property mortgaged and
pledged, the nature and extent of the security, the rights of the holders of the bonds and of the
Trustee in respect thereof, the duties and immunities of the Trustee, the terms and conditions
upon which the bonds are and are to be secured and the circumstances under which additional
bonds may be issued. If there shall be a conflict between the terms of this bond and the
provisions of the Mortgage, the provisions of the Mortgage shall control to the extent permitted
by law. The holder of this bond, by its acceptance hereof, shall be deemed to have consented
and agreed to all of the terms and provisions of the Mortgage and, further, in the event that such
holder shall not be the sole beneficial owner of this bond, shall be deemed to have agreed to use
all commercially reasonable efforts to cause all direct and indirect beneficial owners of this bond
to have knowledge of the terms and provisions of the Mortgage and of this bond and to comply
therewith, including particularly, but without limitation, any provisions or restrictions in the
Mortgage regarding the transfer or exchange of such beneficial interests and any legend set forth
on this bond.
E-2

The Mortgage may be modified or altered by affirmative vote of the holders of at
least 60% in principal amount of the bonds outstanding under the Mortgage, considered as one
class, or, if the rights of one or more, but less than all, series of bonds then outstanding are to be
affected, then such modification or alteration may be effected with the affirmative vote only of
60% in principal amount of the bonds outstanding of the series so to be affected, considered as
one class, and, furthermore, for limited purposes, the Mortgage may be modified or altered
without any consent or other action of holders of any series of bonds. No modification or
alteration shall, however, permit an extension of the Maturity of the principal of, or interest on,
this bond or a reduction in such principal or the rate of interest hereon or any other modification
in the terms of payment of such principal or interest or the creation of any lien equal or prior to
the lien of the Mortgage or deprive the holder of a lien on the mortgaged and pledged property
without the consent of the holder hereof. Each initial and subsequent holder of bonds of this
series, by virtue of its acquisition of an interest therein, shall be deemed, without further act, to
have consented to the prospective amendments to the Original Mortgage set forth or referred to
in the Seventieth Supplemental Indenture.
The principal hereof, together with all accrued and unpaid interest hereon (but
without premium), may be declared or may become due prior to the Stated Maturity Date on the
conditions, in the manner and at the time set forth in the Mortgage, upon the occurrence of a
Completed Default as in the Mortgage provided.
As provided in the Mortgage and subject to certain limitations therein set forth,
this bond or any portion of the principal amount hereof will be deemed to have been paid if there
has been irrevocably deposited with the Trustee moneys or direct obligations of or obligations
guaranteed by the United States of America, the principal of and interest on which when due, and
without regard to any reinvestment thereof, will provide moneys which, together with moneys so
deposited, will be sufficient to pay when due the principal of and premium, if any, and interest
on this bond when due.
The Mortgage contains terms, provisions and conditions relating to the
consolidation or merger of the Company with or into, and the conveyance or other transfer, or
lease, of assets to, another corporation and to the assumption by such other corporation, in certain
circumstances, of all of the obligations of the Company under the Mortgage and on the bonds
secured thereby.
In the manner prescribed in the Mortgage, this bond is transferable by the
registered owner hereof in person, or by his duly authorized attorney, at the office or agency of
the Company in the Borough of Manhattan, The City of New York, upon surrender and
cancellation of this bond, together with a written instrument of transfer whenever required by the
Company duly executed by the registered owner or by its duly authorized attorney, and,
thereupon, a new fully registered bond of the same series for a like principal amount will be
issued to the transferee in exchange herefor as provided in the Mortgage. The Company and the
Trustee may deem and treat the person in whose name this bond is registered as the absolute
owner hereof for the purpose of receiving payment and for all other purposes.
In the manner prescribed in the Mortgage, any bonds of this series, upon
surrender thereof for cancellation at the office or agency of the Company in the Borough of
E-3

Manhattan, The City of New York, are exchangeable for a like aggregate principal amount of
bonds of the same series of other authorized denominations.
Any bond of this series authenticated and delivered upon the transfer or exchange
of a bond prior to the first Interest Payment Date to which interest on all outstanding bonds of
this series has been paid shall have the same Initial Interest Accrual Date as the bond surrendered
in such transfer or exchange.
Prior to the Par Call Date (as hereinafter defined), the bonds of this series shall be
redeemable in whole at any time or in part from time to time, at the option of the Company, upon
notice mailed as provided in Section 52 of the Mortgage, at a redemption price equal to the
greater of
(a) 100% of the principal amount of the bonds being redeemed and
(b) (i) the sum of the present values of the remaining scheduled payments
of principal of and interest on the bonds being redeemed (assuming, for this purpose, that
the bonds of this series were stated to mature on the Par Call Date), discounted to the date
of redemption on a semiannual basis (assuming a 360-day year consisting of twelve 30-
day months) at a discount rate equal to the Treasury Yield(as hereinafter defined)plus 50
basis points, less (ii) interest accrued to the redemption date,
plus, in the case of either (a) or (b) above, whichever is applicable, accrued and unpaid interest
on such bonds to the date of redemption.
On or after the Par Call Date, the bonds of this series shall be redeemable in
whole at any time, or in part from time to time, at the option of the Company,upon notice mailed
as aforesaid, at a redemption price equal to 100% of the principal amount of the bonds being
redeemed plus accrued and unpaid interest on such bonds to the date of redemption.
"Par Call Date" means November 1, 2055.
"Treasury Yield" has the meaning set forth in the Seventieth Supplemental
Indenture.
If the Company shall have reasonably determined that it is reasonably likely that
any Purchaser's (as defined in the Bond Purchase Agreement) is a "specified foreign entity" (as
defined in Section 7701(a)(51)(B) of the Internal Revenue Code of 1986, as amended), then the
bonds of this series held by such Purchaser shall be redeemable in whole at any time, or in part
from time to time, at the option of the Company, at a redemption price of 100% of the principal
amount of the bonds to be redeemed plus accrued and unpaid interest to the date of redemption.
If there shall be more than one such Purchaser, the Company shall determine the Purchaser or
Purchasers whose bonds of the series are to be redeemed in accordance with this paragraph and
the principal amount of bonds of each such Purchaser to be redeemed.
Except as provided above, (a)the bonds of this series are not redeemable prior to
the Stated Maturity Date and (b) no amount other than the principal of and interest on the bonds
of this series shall be payable in respect of such bonds at Maturity or otherwise.
E-4

No recourse shall be had for the payment of the principal of or premium, if any, or
interest on this bond against any incorporator or any past, present or future subscriber to the
capital stock, stockholder, officer or director of the Company or of any predecessor or successor
corporation, as such, either directly or through the Company or any predecessor or successor
corporation, under any rule of law, statute or constitution or by the enforcement of any
assessment or otherwise, all such liability of incorporators, subscribers, stockholders, officers
and directors being released by the holder or owner hereof by the acceptance of this bond and
being likewise waived and released by the terms of the Mortgage.
This bond shall not become obligatory until Citibank, N.A., the Trustee under the
Mortgage, or its successor thereunder, shall have signed the form of certificate endorsed hereon.
E-5

ASSIGNMENT FORM
FOR VALUE RECEIVED the undersigned hereby sells, assigns and transfers unto
[please insert social security or other identifying number of assignee]
[please print or typewrite name and address of assignee]
the within bond of AVISTA CORPORATION and does hereby irrevocably constitute and
appoint , Attorney, to transfer said bond
on the books of the within-mentioned Company, with full power of substitution in the premises.
Dated:
[signature of assignor]
Notice: The signature to this assignment must correspond with the name as written upon the face
of the bond in every particular without alteration or enlargement or any change whatsoever.
E-6

AVISTA CORPORATION
Private Placement of First Mortgage Bonds
$[140],000,000 Series due 2056
$[90],000,000 Series due 2029
Summary of Proposed Terms
The securities being offered will be two new series of First Mortgage Bonds (the "Bonds") issued
under the Mortgage and Deed of Trust, dated as of June 1, 1939, from Avista Corporation (the
"Company")to Citibank,N.A.,successor trustee,as amended and supplemented(the"Mortgage").
The new series of bonds will be created, and the terms thereof will be set forth, in the Seventieth
Supplemental Indenture, to be dated as of May 1, 2026 (the "Supplemental Indenture"). The form
of Supplemental Indenture, which has been prepared by Bracewell LLP, counsel to the Company,
has been posted to the Intralinks site.
Each series of the new Bonds will be sold pursuant to a separate Bond Purchase Agreement between
Avista Corporation and the Purchasers of Bonds of that series. The forms of the Bond Purchase
Agreements,which have been prepared by Choate,Hall& Stewart LLP,counsel to the Purchasers,
have also been posted to the Intralinks site.The Bond Purchase Agreements are based on the Model
Form No.2, except that the provisions relating to the new Bonds,the terms thereof and the security
therefor are found in the Mortgage including the Supplemental Indenture. The transactions
contemplated by the two Bond Purchase Agreements are separate transactions,not contingent upon
each other.
This summary does not cover all aspects of the transaction and is qualified in its entirety by the
Mortgage. See the Description of Avista Mortgage which has also been posted on Intralinks.
These securities are not being offered to any entity that is a "specified foreign entity" (as
defined in section 7701(a)(51)(B) of the Internal Revenue Code of 1986, as amended). See No
"Specified Foreign Entities" below.
Issuer Avista Corporation
Issue(s) First Mortgage Bonds to be issued under the Mortgage.
Principal Amount Aggregate of$230,000,000 which, at the option of the Company,
may be increased or decreased, in two series.
Maturities • 30 -year bullet maturity(May 1, 2056)— [$140,000,000]
• 3 -year bullet maturity(May 1, 2029)— [$90,000,000]
Closing and May [ ], 2026; part of the 2056 series may fund later (but not later
Funding than August ,2026).
Issue Price Par.

Interest Rate Margin will be determined via an auction process, with a spread
added to the yield on the comparable Treasury Notes. Interest will
be payable semi-annually in arrears, computed on the basis of
twelve 30-day months in a year of 360 days.
Ranking The Bonds will be senior secured obligations of the Company,
ranking pari passu in all respects with the Company's other First
Mortgage Bonds outstanding under the Mortgage.
Security The Bonds(but not the Company's covenants under Bond Purchase
Agreement) will be secured, pari passu with other bonds
outstanding under the Mortgage, by a first lien on the Company's
facilities for the generation,transmission and distribution of electric
energy and the storage and distribution of natural gas, subject to
"excepted encumbrances" (as defined in the Mortgage) and other
encumbrances, defects or irregularities that are not material in the
operation of the Company's business.
Use of Proceeds Net proceeds from the sale of the Bonds will be used for the
construction or improvement of utility facilities, to refinance
existing indebtedness incurred for such purposes, or to reimburse
the treasury for moneys expended for such purposes.
Optional Redemption Prior to the Par Call Date, the Bonds shall be redeemable at any
time,at the option of the Company,in whole or in part,at the Make-
Whole Price. The "Make-Whole Price" will be defined as the
greater of
(i) par or
(ii) the present value of the remaining principal and interest
payments due on the Bonds discounted by the yield on
the
U.S. Treasury constant maturity corresponding to the
remaining life of the Bonds (assuming for this purpose
that the stated maturity date were the Par Call Date)plus
50 basis points, less accrued interest to the redemption
date,
plus, in any case, accrued and unpaid interest.
On or after the Par Call Date, the Bonds may be redeemed at any
time, in whole or in part, at the option of the Company, at a
redemption price equal to one hundred percent of the principal
amount of the series being redeemed, plus accrued and unpaid
interest but without make-whole premium.
For the Bonds maturing on May 1, 2056, the Par Call Date is
November 1,2055

For the Bonds maturing on May 1, 2029, the Par Call Date is April
1, 2029
Covenants in Bond • Quarterly and annual financial statements of the
Purchase Company (satisfied by filing SEC reports);
Agreement . SEC and other reports and notices of defaults;
• Additional requested information and visitation and
inspection rights;
• Compliance with law;
• Terrorism sanctions regulations; and
• Expenses
Covenants in • Delivery of financial statements, reports, officers'
Mortgage certificates and other information set forth in the Mortgage
(as required by the Trust Indenture Act of 1939);
• Possession and maintenance of mortgaged property free
and clear of Liens (subject to certain exceptions);
• Maintenance of property and insurance;
• Payment of taxes and claims;
• Corporate existence;
• Maintenance of books and records;
• Merger and consolidation; and
• Limitations on release of collateral.
Additional Bonds Additional bonds may be issued under the Mortgage on the basis of
• 66 2/3%of cost or fair value to the Company(whichever is
less) of property additions which have not previously been
made the basis of any application under the Mortgage;
• an equal principal amount of other bonds outstanding under
the Mortgage which have been or are to be paid,redeemed
or otherwise retired; or
• deposit of cash.
In general, Avista may not issue additional bonds on the basis of
property additions or cash unless net earnings for 12 consecutive
months out of the preceding 18 calendar months (before income
taxes, depreciation and amortization, property losses and interest
on indebtedness and amortization of debt discount and expense)are
at least twice the annual interest requirement on all bonds at the
time outstanding under the Mortgage including the additional
bonds.

The Company is required to satisfy the net earning requirements
prior to the issuance of additional bonds on the basis of retired
bonds if
• the annual interest requirements on such retired bonds have
been excluded from a net earnings certificate delivered since
the retirement of such bonds; or
• the retired bonds mature more than two years after the
issuance date of the bonds proposed to be issued and the new
bonds will bear interest at a higher rate than the retired bonds.
Events of Default Events of default under the Mortgage are:
• Failure to pay principal or premium when due at maturity
or otherwise;
• Failure to pay interest within 60 days of due date;
• Failure to perform any of the covenants for 90 days after
notice to the Company from the Trustee;
• Failure to pay interest on,or principal of any qualified prior
lien bonds beyond any grace period specified in the prior
lien securing such prior lien bonds; or
• Certain events of bankruptcy or insolvency of the Company.
Events of Default do not include violations of the Bond Purchase
Agreement.
Acceleration If an Event of Default has occurred and is continuing, the Trustee
may, and upon the request of holders of a majority in principal
amount of all bonds outstanding under the Mortgage shall, declare
the principal of and accrued interest on all Mortgage bonds
immediately due and payable.
No premium on the Bonds, or any other series of Mortgage bonds,
would be payable upon any such acceleration.
Conditions Usual and customary for transactions of this type.
Precedent
Amendment of The Mortgage may be amended with the consent of the holders of
Mortgage 60% in principal amount of the affected series of Mortgage bonds,
considered as one class; provided, that the Mortgage may also be
amended in certain limited respects without the consent of
bondholders.

Definitions Definitions will be as set forth in the Mortgage and the Bond
Purchase Agreement.
Counsel to Bond Choate, Hall & Stewart LLP will represent the Purchasers in
Purchasers connection with their purchase of the Bonds.
Counsel to Bracewell LLP, which regularly represents the Company in
Company corporate and securities matters, will represent the Company in
connection with the issuance and sale of the Bonds.
Joint Lead Agents J.P. Morgan Securities LLC
Keybanc Capital Markets Inc.
U.S. Bancorp Investments, Inc.
Expenses Company will pay all reasonable and documented out-of-pocket
costs and expenses (including reasonable attorneys' fees of one
special counsel for all holders) incurred by the Bond purchasers in
connection with the transaction.
No "Specified This offering is not being made to any investor that is a "specified
Foreign Entities" foreign entity"(as defined in Section 770 1(a)(5 1)(B)of the Internal
revenue Code of 1986, as amended).
Each Purchaser will represent that it is not a "specified foreign
entity" and will agree to indemnify the Company for all losses and
damages (including loss of renewable energy tax credits) incurred
if such Purchaser is a"specified foreign entity".
If the Company reasonably determines that it is reasonably likely
that any Purchaser is a"specified foreign entity",the Bonds held by
such Purchaser will be redeemable in whole at any time, or in part
from time to time, at the option of the Company, at 100% of the
principal amount thereof plus accrued interest.