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As filed with the Securities and Exchange Commission on June 20, 2011

Registration No. 333-            

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

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FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

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BLACK HILLS CORPORATION
(Exact name of registrant as specified in its charter)

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625 Ninth Street
Rapid City, South Dakota 57701
(605) 721-1700
(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)

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Steven J. Helmers, Esq.
Senior Vice President—General Counsel
625 Ninth Street
Rapid City, South Dakota 57701
(605) 721-2303
(Name, address, including zip code, and telephone number, including area code, of agent for service)

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WITH COPIES TO:

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           Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this registration statement.

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           If the only securities being registered on this form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o

           If any of the securities being registered on this form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. ý

           If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

           If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

           If this form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ý

           If this form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. o

           Indicate by check mark whether the Registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act. (Check one)

CALCULATION OF REGISTRATION FEE

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PROSPECTUS

BLACK HILLS CORPORATION

Senior Debt Securities
Subordinated Debt Securities
Preferred Stock
Depositary Shares
Common Stock
Warrants
Purchase Contracts
Units

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        We may from time to time offer to sell senior debt securities, subordinated debt securities, preferred stock, depositary shares, common stock, warrants, purchase contracts or units. Each time we sell securities pursuant to this prospectus, we will provide a supplement to this prospectus that contains specific information about the offering and the specific terms of the securities offered. You should read this prospectus and the applicable prospectus supplement carefully before you invest in our securities.

        Our common stock is listed on the New York Stock Exchange under the symbol "BKH."

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        There are significant risks associated with an investment in our securities. You should read carefully the risks we describe in the accompanying prospectus supplement as well as the risk factors discussed in our periodic reports that we file with the Securities and Exchange Commission, for a better understanding of the risks and uncertainties that investors in our securities should consider.

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        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

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        This prospectus may not be used to sell securities unless accompanied by a prospectus supplement.

The date of this prospectus is June 20, 2011.

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        You should rely only on the information contained in this prospectus or any prospectus supplement to which we have referred you. We have not authorized anyone to provide you with information that is different. This prospectus may only be used where it is legal to sell these securities. The information in this prospectus or any prospectus supplement may only be accurate on the date of those documents.

ABOUT THIS PROSPECTUS

        This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, or the SEC, utilizing a "shelf" registration process. Under this shelf process, we may, from time to time, sell any combination of the securities described in this prospectus in one or more offerings. For further information about our business and the securities, you should refer to the registration statement and its exhibits. The exhibits to the registration statement and the documents incorporated by reference in the registration statement contain the full text of the contracts and other important documents summarized in this prospectus. Since these summaries may not contain all the information that you may find important in deciding whether to purchase the securities that we may offer, you should review the full text of these documents. The registration statement can be obtained from the SEC as indicated under the heading "Where You Can Find More Information."

        This prospectus provides you with only a general description of the securities we may offer. Each time we offer to sell securities, we will provide a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement may also add, update, or change information contained in this prospectus. If there is any inconsistency between the information in this prospectus and any prospectus supplement, you should rely on the information in the prospectus supplement. You should read both this prospectus and any prospectus supplement together with the additional information described under the heading "Where You Can Find More Information." Unless the context otherwise requires, references in this prospectus to "Black Hills," the "Company," "we," "us" and "our" refer to Black Hills Corporation and all of its subsidiaries collectively.

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DISCLOSURE REGARDING FORWARD-LOOKING STATEMENTS

        This prospectus, any accompanying prospectus supplement and the documents incorporated by reference herein and therein may include forward-looking statements as defined by the SEC. We make these forward-looking statements in reliance on the safe harbor protections provided under the Private Securities Litigation Reform Act of 1995. All statements, other than statements of historical facts, included in this prospectus, any accompanying prospectus supplement and the documents incorporated by reference herein and therein that address activities, events or developments that we expect, believe or anticipate will or may occur in the future are forward-looking statements. These forward-looking statements are based on assumptions which we believe are reasonable based on current expectations and projections about future events and industry conditions and trends affecting our business. However, whether actual results and developments will conform to our expectations and predictions is subject to a number of risks and uncertainties that, among other things, could cause actual results to differ materially from those contained in the forward-looking statements, including without limitation the Risk Factors set forth in Item 1A of our Annual Report on Form 10-K for the year ended December 31, 2010, and in other reports that we file with the SEC from time to time, and the following:

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Macro- and micro-economic changes in the economy and energy industry, including the impact of (i) consolidations and changes in competition, and (ii) general economic and political conditions, including tax rates or policies and inflation rates;



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The timing, volatility and extent of changes in energy and commodity prices, supply or volume, the cost and availability of transportation of commodities, changes in interest or foreign exchange rates, and the demand for our services, any of which can affect our earnings, our financial liquidity and the underlying value of our assets;



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Our ability to comply, or to make expenditures required to comply, with changes in laws and regulations, particularly those relating to energy markets, taxation, safety and protection of the environment, and our ability to recover those expenditures in customer rates, where applicable;



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Federal and state laws concerning climate change and air emissions, including emission reduction mandates, carbon emissions and renewable energy portfolio standards, which may materially increase our generation and production costs and could render some of our generating units uneconomical to operate and maintain, or which could require closure of one or more of our generating units;



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Changes in business, regulatory compliance and financial reporting practices arising from the enactment of the Energy Policy Act of 2005 and subsequent rules and regulations promulgated thereunder;



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The effect of the Dodd-Frank Act and the regulations to be adopted thereunder on our use of derivative instruments in connection with our energy marketing activities and to hedge our expected production of oil and natural gas and on our use of interest rate derivative instruments;



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Changes in state laws or regulations that could cause us to curtail our independent power production or exploration and production activities;



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Our ability to successfully integrate and profitably operate any future acquisitions;



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Our ability to obtain adequate cost recovery for our utility operations through regulatory proceedings and receive favorable rulings in periodic applications to recover costs for fuel, transportation, transmission and purchased power in our regulated utilities;



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Our ability to receive regulatory approval to recover in rate base our expenditures for new power generation facilities or other utility infrastructure;

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Our ability to recover our borrowing costs, including debt service costs, in our customer rates;



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The extent of our success in connecting natural gas supplies to gathering, processing and pipeline systems;



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Our ability to minimize losses related to defaults on amounts due from customers and counterparties, including counterparties to trading and other commercial transactions;



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The timing and extent of scheduled and unscheduled outages of power generation facilities;



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Our ability to complete the permitting, construction, start-up and operation of power generating facilities in a cost-effective and timely manner;



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Our ability to accurately estimate demand from our customers for natural gas;



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Weather and other natural phenomena;



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Our ability to meet forecasted production volumes for our oil and gas properties, which may be dependent upon issuance by federal, state and tribal governments, or agencies thereof, of drilling, environmental and other permits, and the availability of specialized contractors, work force and equipment, or the possibility of reductions in our drilling program resulting from the current economic climate and commodity prices, which also may prevent us from maintaining production rates and replacing reserves for our oil and gas properties;



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The amount of collateral required to be posted from time to time in our transactions;



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Our ability to effectively use derivative financial instruments to hedge commodity, currency exchange rate and interest rate risks;



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Our ability to provide accurate estimates of proved oil and gas reserves, coal reserves and future production rates and associated costs;



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Price risk due to marketable securities held as investments in employee benefit plans;



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Our ability to successfully maintain our corporate credit rating;



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Our ability to access revolving credit capacity and comply with loan covenants;



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Capital market conditions and market uncertainties related to interest rates, which may affect our ability to raise capital on favorable terms;



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The amount and timing of capital deployment in new investment opportunities or for the repurchase of debt or stock;



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Our ability to continue paying our regular quarterly dividend;



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Our ability to obtain permanent financing for capital expenditures on reasonable terms either through long-term debt or issuance of equity;



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The effect of accounting policies issued periodically by accounting standard-setting bodies;



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The accounting treatment and earnings impact associated with interest rate swaps;



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The possibility that we may be required to take impairment charges to reduce the carrying value of some of our long-lived assets when indicators of impairment emerge;



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The possibility that we may be required to take impairment charges under the SEC's full cost ceiling test for the accumulated costs of our natural gas and oil reserves;



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The outcome of any ongoing or future litigation or similar disputes and the impact of any such outcome or related settlements on our financial condition or results of operations;

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Additional liabilities for environmental conditions, including remediation and reclamation obligations, under environmental laws;



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Our ability to successfully complete labor negotiations with labor unions with whom we have collective bargaining agreements and for which we are currently in, or are soon to be in, contract renewal negotiations;



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The cost and effect on our business, including insurance, resulting from terrorist actions or responses to such actions or events;



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General economic and political conditions, including tax rates or policies and inflation rates; and



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Risk factors discussed in any accompanying prospectus supplement.

        New factors that could cause actual results to differ materially from those described in forward-looking statements emerge from time to time, and it is not possible for us to predict all such factors, or the extent to which any such factor or combination of factors may cause actual results to differ from those contained in any forward-looking statement. We assume no obligation to update publicly any such forward-looking statements, whether as a result of new information, future events or otherwise.

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BLACK HILLS CORPORATION

        We are a diversified energy company. Our predecessor company, Black Hills Power and Light Company, was incorporated and began providing electric utility service in 1941 and began selling and marketing various forms of energy on an unregulated basis in 1956. We operate principally in the United States with two major business groups: utilities and non-regulated energy. Our utilities group is comprised of our regulated electric utilities and regulated gas utilities segments, and our non-regulated energy group is comprised of our oil and gas, power generation, coal mining, and energy marketing segments.

        Our electric utilities segment generates, transmits and distributes electricity to approximately 201,000 customers in South Dakota, Wyoming, Colorado and Montana. This segment includes the operations of our subsidiary Cheyenne Light, Fuel and Power Company, a combination electric and gas utility, and its approximately 34,500 gas utility customers in Wyoming. Our electric utilities own 687 megawatts of generation and 8,038 miles of electric transmission and distribution lines. Our gas utilities segment serves approximately 527,000 natural gas utility customers in Colorado, Nebraska, Iowa and Kansas and owns 626 miles of intrastate gas transmission pipelines and 19,638 miles of gas distribution mains and service lines. Our electric and gas utilities generated income from continuing operations of $74.6 million for the year ended December 31, 2010 and had total assets of $2.6 billion at December 31, 2010.

        Our non-regulated energy group conducts business in four segments:

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Oil and Gas.  Our oil and gas segment engages in the exploration, development and production of crude oil and natural gas, primarily in the Rocky Mountain region of the United States.



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Power Generation.  Our power generation segment produces electric power from our generating plants and sells the electric capacity and energy primarily under long-term contracts.



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Coal Mining.  Our coal mining segment produces coal at our coal mine near Gillette, Wyoming.



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Energy Marketing.  Our energy marketing segment is engaged in marketing of natural gas, crude oil, coal, power, environmental products, renewable energy sources (such as biomass) and related products and services in the United States and Canada.

        Our non-regulated energy group generated income from continuing operations of $13.6 million in the year ended December 31, 2010 and had total assets of $1.1 billion at December 31, 2010.

        Our oil and gas segment, which conducts business through our subsidiary Black Hills Exploration and Production, Inc., or BHEP, and its subsidiaries, acquires, explores for, develops and produces natural gas and crude oil for sale into commodity markets. As of December 31, 2010, the principal assets of our oil and gas segment included operating interests in oil and natural gas properties, including properties in the San Juan Basin (primarily New Mexico, including holdings within the tribal lands of the Jicarilla Apache and Southern Ute Nations), the Powder River Basin (Wyoming) and the Piceance Basin (primarily in Colorado) and non-operated interests in oil and natural gas properties including wells located in the Williston (Bakken Shale primarily in North Dakota), Wind River (Wyoming), Bearpaw Uplift (Montana), Arkoma (Oklahoma), Anadarko (Texas) and Sacramento (California) basins. We also own a 44.7% non-operated interest in the Newcastle gas processing plant and associated gathering system located in Weston County, Wyoming. The plant is adjacent to our producing properties in that area, and BHEP's production accounts for the majority of the facility's throughput. In addition, we own natural gas gathering, compression and treating facilities serving the operated San Juan and Piceance Basin properties and working interests in similar facilities serving our non-operated Montana and Wyoming properties. At December 31, 2010, we had total reserves of approximately 131 Bcfe, of which natural gas comprised 73% and oil comprised 27% of total reserves.

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        Our power generation segment acquires, develops and operates our non-regulated power plants. As of December 31, 2010, we held varying interests in independent power plants operating in Wyoming and Idaho with a total net ownership of 120 megawatts. In January 2011, we sold our ownership interests in the Idaho partnerships that own the Idaho facilities. We sell capacity and energy under a combination of mid- to long-term contracts, which mitigates the impact of a potential downturn in future power prices. We currently sell a substantial majority of our non-regulated generating capacity under contracts having terms greater than one year. We sell additional power into the wholesale power markets from our generating capacity when it is available and economical.

        Our coal mining segment, which operates through our Wyodak Resources Development Corp. subsidiary, mines and processes low-sulfur, sub-bituminous coal at our Wyodak coal mine located in the Powder River Basin near Gillette, Wyoming. The Powder River Basin contains one of the largest coal reserves in the United States. We produced approximately 5.9 million tons of coal in 2010.

        Through our subsidiary, Enserco, we engage in natural gas, crude oil, coal, power, environmental product and renewable energy source (such as biomass) marketing and trading in the United States and Canada. Our marketing operations are headquartered in Denver, Colorado, with a satellite sales office in Calgary, Alberta, Canada. Our energy marketing business seeks to provide services to producers and end-users of natural gas, crude oil, coal, power, environmental products and renewable energy sources and to capitalize on market volatility by employing certain risk-managed commodity trading strategies. We began marketing coal in June 2010 with the acquisition of a coal marketing business, we began power and environmental marketing late in the third quarter of 2010, and we began renewable energy source marketing in the second quarter of 2011. We believe that the diversity of the commodities portfolio that we market and the service provider focus of our energy marketing activities differentiate us from other energy marketers.

        We are a South Dakota corporation. Our common stock is listed on the New York Stock Exchange under the symbol "BKH." Our principal and executive offices are located at 625 Ninth Street, Rapid City, South Dakota 57701 and our telephone number is (605) 721-1700. Our Internet address is www.blackhillscorp.com. Information on our website does not constitute part of this prospectus.

RATIO OF EARNINGS TO FIXED CHARGES

        The following table sets forth our ratio of earnings to fixed charges. For this purpose, earnings consist of income from continuing operations (before adjustment for income taxes, minority interests in consolidated subsidiaries or income or loss from equity investees), plus fixed charges, amortization of capitalized interest and distributed income of equity investees and less interest capitalized, preference security dividend requirements of consolidated subsidiaries and minority interest in pre-tax income of subsidiaries that have not incurred fixed charges. Fixed charges consist of interest expensed and capitalized, amortization of debt issuance costs and an estimate of the interest within rental expense.

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USE OF PROCEEDS

        Unless otherwise indicated in the applicable prospectus supplement, we intend to use the net proceeds from the sale of any securities described in this prospectus for working capital and general corporate purposes, which may include:

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repayment or refinancing of outstanding debt;



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capital expenditures;



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acquisitions;



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investments; and



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other business opportunities.

DESCRIPTION OF SENIOR DEBT SECURITIES

General

        The following description applies to the senior debt securities offered by this prospectus. The senior debt securities will be direct, unsecured obligations of Black Hills and will rank on a parity with all of our outstanding unsecured senior indebtedness. The senior debt securities may be issued in one or more series. The senior debt securities will be issued under an indenture between us and the trustee specified in the applicable prospectus supplement.

        The statements under this caption are brief summaries of the provisions contained in the indenture, do not claim to be complete and are qualified in their entirety by reference to the indenture, a copy of which is filed as an exhibit to the registration statement of which this prospectus forms a part. Whenever defined terms are used but not defined in this prospectus, those terms have the meanings given to them in the indenture.

        The following describes the general terms and provisions of the senior debt securities to which any prospectus supplement may relate. The particular terms of any senior debt security and the extent, if any, to which these general provisions may apply to the senior debt securities will be described in the prospectus supplement relating to the senior debt securities.

        The indenture does not limit the aggregate principal amount of senior debt securities which may be issued under it. Rather, the indenture provides that senior debt securities of any series may be issued under it up to the aggregate principal amount which we may authorize from time to time. Senior debt securities may be denominated in any currency or currency unit we designate. Neither the indenture nor the senior debt securities will limit or otherwise restrict the amount of other debt which we may incur or the other securities which we may issue.

        Senior debt securities of a series may be issuable in registered form without coupons, which we refer to as "registered securities," or in the form of one or more global securities in registered form, which we refer to as "global securities."

        You must review the prospectus supplement for a description of the following terms, where applicable, of each series of senior debt securities for which this prospectus is being delivered:

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the title of the senior debt securities;



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the limit, if any, on the aggregate principal amount or aggregate initial public offering price of the senior debt securities;



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the priority of payment of the senior debt securities;

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the price or prices, which may be expressed as a percentage of the aggregate principal amount, at which the senior debt securities will be issued;



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the date or dates on which the principal of the senior debt securities will be payable;



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the interest rate or rates, which may be fixed or variable, for the senior debt securities, if any, or the method of determining the same;



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the date or dates from which interest, if any, on the senior debt securities will accrue, the date or dates on which interest, if any, will be payable, the date or dates on which payment of interest, if any, will commence and the regular record dates for the interest payment dates;



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the extent to which any of the senior debt securities will be issuable in temporary or permanent global form, or the manner in which any interest payable on a temporary or permanent global senior debt security will be paid;



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each office or agency where the senior debt securities may be presented for registration of transfer or exchange;



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the place or places where the principal of and any premium and interest on the senior debt securities will be payable;



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the date or dates, if any, after which the senior debt securities may be redeemed or purchased in whole or in part, (1) at our option or (2) mandatorily pursuant to any sinking, purchase or similar fund or (3) at the option of the holder, and the redemption or repayment price or prices;



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the terms, if any, upon which the senior debt securities may be convertible into or exchanged for any other kind of our securities or indebtedness and the terms and conditions upon which the conversion or exchange would be made, including the initial conversion or exchange price or rate, the conversion period and any other additional provisions;



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the authorized denomination or denominations for the senior debt securities;



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the currency, currencies or units based on or related to currencies for which the senior debt securities may be purchased and the currency, currencies or currency units in which the principal of and any premium and interest on the senior debt securities may be payable;



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any index used to determine the amount of payments of principal of and any premium and interest on the senior debt securities;



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the payment of any additional amounts with respect to the senior debt securities;



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whether any of the senior debt securities will be issued with original issue discount;



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information with respect to book-entry procedures, if any;



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any additional covenants or events of default not currently included in the indenture relating to the senior debt securities; and



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any other terms of the senior debt securities not inconsistent with the provisions of the indenture.

        If any of the senior debt securities are sold for one or more foreign currencies or foreign currency units or if the principal of or any premium or interest on any series of senior debt securities is payable in one or more foreign currencies or foreign currency units, the restrictions, elections, tax consequences, specific terms and other information with respect to that issue of senior debt securities and those currencies or currency units will be described in the applicable prospectus supplement.

        A judgment for money damages by courts in the United States, including a money judgment based on an obligation expressed in a foreign currency, will ordinarily be rendered only in U.S. dollars.

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New York statutory law provides that a court shall render a judgment or decree in the foreign currency of the underlying obligation and that the judgment or decree shall be converted into U.S. dollars at the exchange rate prevailing on the date of entry of the judgment or decree.

        Senior debt securities may be issued as original issue discount senior debt securities, which bear no interest or interest at a rate which at the time of issuance is below market rates, to be sold at a substantial discount below their stated principal amount due at the stated maturity of the senior debt securities. There may be no periodic payments of interest on original issue discount securities. In the event of an acceleration of the maturity of any original issue discount security, the amount payable to the holder of the original issue discount security upon acceleration will be determined in accordance with the prospectus supplement, the terms of the security and the indenture, but will be an amount less than the amount payable at the maturity of the principal of the original issue discount security.

        If the senior debt securities are issued with "original issue discount" within the meaning of the Internal Revenue Code of 1986, as amended, then a holder of those senior debt securities will be required under the Internal Revenue Code to include original issue discount in ordinary income for federal income tax purposes as it accrues, in accordance with a constant interest method that takes into account the compounding of interest, in advance of receipt of cash attributable to that income. Generally, the total amount of original issue discount on a senior debt security will be the excess of the stated redemption price at maturity of the security over the price at which the security is sold to the public. To the extent a holder of a senior debt security receives a payment (at the time of acceleration of maturity, for example) that represents payment of original issue discount already included by the holder in ordinary income or reflected in the holder's tax basis in the security, that holder generally will not be required to include the payment in income. The specific terms of any senior debt securities that are issued with original issue discount and the application of the original discount rules under the Internal Revenue Code to those securities will be described in a prospectus supplement for those securities.

Registration and Transfer

        Unless otherwise indicated in the applicable prospectus supplement, senior debt securities will be issued only as registered securities. Senior debt securities issued as registered securities will not have interest coupons.

        Registered securities (other than a global security) may be presented for transfer, with the form of transfer endorsed thereon duly executed, or exchanged for other senior debt securities of the same series at the office of the security registrar specified in the indenture. The indenture provides that, with respect to registered securities having The City of New York as a place of payment, we will appoint a security registrar or co-security registrar located in The City of New York for such transfer or exchange. Transfer or exchange will be made without service charge, but we may require payment of any taxes or other governmental charges.

Book-Entry Senior Debt Securities

        Senior debt securities of a series may be issued in whole or in part in the form of one or more global securities. Each global security will be deposited with, or on behalf of, a depositary identified in the applicable prospectus supplement. Global securities will be issued in registered form and in either temporary or permanent form. Until exchanged in whole or in part for the individual securities which it represents, a global security may not be transferred except as a whole by the depositary for the global security to a nominee of the depositary or by a nominee of the depositary to the depositary or another nominee of the depositary or by the depositary or any nominee to a successor depositary or any nominee of the successor. The specific terms of the depositary arrangement for a series of senior debt securities will be described in the applicable prospectus supplement.

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Payment and Paying Agents

        Unless otherwise indicated in an applicable prospectus supplement, payment of principal of and any premium and interest on registered securities will be made at the office of such paying agent or paying agents as we may designate from time to time. In addition, at our option, payment of any interest may be made by:

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check mailed to the address of the person entitled to the payment at the address in the applicable security register; or



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wire transfer to an account maintained by the person entitled to the payment as specified in the applicable security register.

        Unless otherwise indicated in an applicable prospectus supplement, payment of any installment of interest on registered securities will be made to the person in whose name the senior debt security is registered at the close of business on the regular record date for the payment.

Consolidation, Merger or Sale of Assets

        The indenture relating to the senior debt securities provides that we may, without the consent of the holders of any of the senior debt securities outstanding under the indenture, consolidate with, merge into or transfer our assets substantially as an entirety to any person, provided that:

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any successor assumes our obligations on the senior debt securities and under the indenture; and



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after giving effect to the consolidation, merger or transfer, no event of default (as defined in the indenture) will have happened and be continuing.

        Any consolidation, merger or transfer of assets substantially as an entirety, which meets the conditions described above, would not create an event of default which would entitle holders of the senior debt securities, or the trustee acting on their behalf, to take any of the actions described below under "—Events of Default, Waivers, Etc."

Leveraged and Other Transactions

        The indenture and the senior debt securities do not contain provisions which would protect holders of the senior debt securities in the event we engaged in a highly leveraged or other transaction which could adversely affect the holders of senior debt securities.

Modification of the Indenture

        The indenture provides that, with the consent of the holders of not less than a majority in aggregate principal amount of the outstanding senior debt securities of each affected series, modifications and alterations of the indenture may be made which affect the rights of the holders of the senior debt securities. However, no modification or alteration may be made without the consent of the holder of each senior debt security affected which would, among other things:

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modify the terms of payment of principal of or any premium or interest on the senior debt securities; or



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reduce the percentage in principal amount of outstanding senior debt securities required to modify or alter the indenture.

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Events of Default, Waivers, Etc.

        An "event of default" with respect to senior debt securities of any series is defined in the indenture to include:

(1)

default in the payment of principal of or any premium on any of the outstanding senior debt securities of that series when due;



(2)

default in the payment of interest on any of the outstanding senior debt securities of that series when due and continuance of such default for 30 days;



(3)

default in the performance of any of our other covenants in the indenture with respect to the senior debt securities of that series and continuance of such default for 60 days after written notice;



(4)

certain events of bankruptcy, insolvency or reorganization relating to us; and



(5)

any other event that may be specified in a prospectus supplement with respect to any series of senior debt securities.

        If an event of default with respect to any series of outstanding senior debt securities occurs and is continuing, either the trustee or the holders of not less than 25% in aggregate principal amount of the outstanding senior debt securities of that series may declare the principal amount (or with respect to original issue discount securities, the portion of the principal amount as may be specified in the terms of that series) of all senior debt securities of that series to be immediately due and payable. The holders of a majority in aggregate principal amount of the outstanding senior debt securities of any series may waive an event of default resulting in acceleration of the senior debt securities, but only if all events of default with respect to senior debt securities of such series have been remedied and all payments due, other than those due as a result of acceleration, have been made.

        If an event of default occurs and is continuing, the trustee may, in its discretion, and at the written request of holders of not less than a majority in aggregate principal amount of the outstanding senior debt securities of any series and upon reasonable indemnity against the costs, expenses and liabilities to be incurred in compliance with such request and subject to certain other conditions set forth in the indenture will, proceed to protect the rights of the holders of all the senior debt securities of that series. Prior to acceleration of maturity of the outstanding senior debt securities of any series, the holders of a majority in aggregate principal amount of the senior debt securities may waive any past default under the indenture except a default in the payment of principal of or any premium or interest on the senior debt securities of that series.

        The indenture provides that upon the occurrence of an event of default specified in clauses (1) or (2) of the first paragraph in this subsection, we will, upon demand of the trustee, pay to it, for the benefit of the holders of any senior debt securities, the whole amount then due and payable on the affected senior debt securities for principal, premium, if any, and interest, if any. The indenture further provides that if we fail to pay such amount upon demand, the trustee may, among other things, institute a judicial proceeding for the collection of those amounts.

        The indenture also provides that notwithstanding any of its other provisions, the holder of any senior debt security of any series will have the right to institute suit for the enforcement of any payment of principal of or any premium or interest on the senior debt securities when due and that such right will not be impaired without the consent of that holder.

        We are required to file annually with the trustee a written statement of our officers as to the existence or non-existence of defaults under the indenture or the senior debt securities.

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Satisfaction and Discharge

        The indenture provides, among other things, that when all senior debt securities not previously delivered to the trustee for cancellation (1) have become due and payable or (2) will become due and payable at their stated maturity within one year, we may deposit with the trustee funds, in trust, for the purpose and in an amount sufficient to pay and discharge the entire indebtedness on the senior debt securities not previously delivered to the trustee for cancellation. Those funds will include all principal, premium, if any, and interest, if any, to the date of the deposit or to the stated maturity, as applicable. Upon such deposit, the indenture will cease to be of further effect except as to our obligations to pay all other sums due under the indenture and to provide the officers' certificates and opinions of counsel required under the indenture. At such time we will be deemed to have satisfied and discharged the indenture.

Governing Law

        The indenture and the senior debt securities will be governed by, and construed in accordance with, the laws of the State of New York.

Regarding the Trustee

        Information concerning the trustee for a series of senior debt securities will be set forth in the prospectus supplement relating to that series of senior debt securities.

        We may have normal banking relationships with the trustee in the ordinary course of business.

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DESCRIPTION OF SUBORDINATED DEBT SECURITIES

General

        The following description applies to the subordinated debt securities offered by this prospectus. The subordinated debt securities will be unsecured, subordinated obligations of Black Hills. The subordinated debt securities may be issued in one or more series. The subordinated debt securities will be issued under an indenture between us and the trustee specified in the applicable prospectus supplement.

        The statements under this caption are brief summaries of the provisions contained in the indenture, do not claim to be complete and are qualified in their entirety by reference to the indenture, a copy of which is filed as an exhibit to the registration statement of which this prospectus forms a part. Whenever defined terms are used but not defined in this prospectus, those terms have the meanings given to them in the indenture.

        The following describes the general terms and provisions of the subordinated debt securities to which any prospectus supplement may relate. The particular terms of any subordinated debt security and the extent, if any, to which these general provisions may apply to the subordinated debt securities will be described in the prospectus supplement relating to the subordinated debt securities.

        The indenture does not limit the aggregate principal amount of subordinated debt securities which may be issued under it. Rather, the indenture provides that subordinated debt securities of any series may be issued under it up to the aggregate principal amount which we may authorize from time to time. Subordinated debt securities may be denominated in any currency or currency unit we designate. Neither the indenture nor the subordinated debt securities will limit or otherwise restrict the amount of other debt which we may incur or the other securities which we may issue.

        Subordinated debt securities of a series may be issuable in the form of registered securities or global securities.

        You must review the prospectus supplement for a description of the following terms, where applicable, of each series of subordinated debt securities for which this prospectus is being delivered:

•

the title of the subordinated debt securities;



•

the limit, if any, on the aggregate principal amount or aggregate initial public offering price of the subordinated debt securities;



•

the priority of payment of the subordinated debt securities;



•

the price or prices, which may be expressed as a percentage of the aggregate principal amount, at which the subordinated debt securities will be issued;



•

the date or dates on which the principal of the subordinated debt securities will be payable;



•

the interest rate or rates, which may be fixed or variable, for the subordinated debt securities, if any, or the method of determining the same;



•

the date or dates from which interest, if any, on the subordinated debt securities will accrue, the date or dates on which interest, if any, will be payable, the date or dates on which payment of interest, if any, will commence and the regular record dates for the interest payment dates;



•

the extent to which any of the subordinated debt securities will be issuable in temporary or permanent global form, or the manner in which any interest payable on a temporary or permanent global subordinated debt security will be paid;



•

each office or agency where the subordinated debt securities may be presented for registration of transfer or exchange;

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•

the place or places where the principal of and any premium and interest on the subordinated debt securities will be payable;



•

the date or dates, if any, after which the subordinated debt securities may be redeemed or purchased in whole or in part, (1) at our option or (2) mandatorily pursuant to any sinking, purchase or similar fund or (3) at the option of the holder, and the redemption or repayment price or prices;



•

the terms, if any, upon which the subordinated debt securities may be convertible into or exchanged for any other kind of our securities or indebtedness and the terms and conditions upon which the conversion or exchange would be made, including the initial conversion or exchange price or rate, the conversion period and any other additional provisions;



•

the authorized denomination or denominations for the subordinated debt securities;



•

the currency, currencies or units based on or related to currencies for which the subordinated debt securities may be purchased and the currency, currencies or currency units in which the principal of and any premium and interest on the subordinated debt securities may be payable;



•

any index used to determine the amount of payments of principal of and any premium and interest on the subordinated debt securities;



•

the payment of any additional amounts with respect to the subordinated debt securities;



•

whether any of the subordinated debt securities will be issued with original issue discount;



•

information with respect to book-entry procedures, if any;



•

the terms of subordination;



•

any additional covenants or events of default not currently included in the indenture relating to the subordinated debt securities; and



•

any other terms of the subordinated debt securities not inconsistent with the provisions of the indenture.

        If any of the subordinated debt securities are sold for one or more foreign currencies or foreign currency units or if the principal of or any premium or interest on any series of subordinated debt securities is payable in one or more foreign currencies or foreign currency units, the restrictions, elections, tax consequences, specific terms and other information with respect to that issue of subordinated debt securities and those currencies or currency units will be described in the applicable prospectus supplement.

        A judgment for money damages by courts in the United States, including a money judgment based on an obligation expressed in a foreign currency, will ordinarily be rendered only in U.S. dollars. New York statutory law provides that a court shall render a judgment or decree in the foreign currency of the underlying obligation and that the judgment or decree shall be converted into U.S. dollars at the exchange rate prevailing on the date of entry of the judgment or decree.

        Subordinated debt securities may be issued as original issue discount securities, to be sold at a substantial discount below their stated principal amount due at the stated maturity of the subordinated debt securities. There may be no periodic payments of interest on original issue discount securities. In the event of an acceleration of the maturity of any original issue discount security, the amount payable to the holder of the original issue discount security upon acceleration will be determined in accordance with the prospectus supplement, the terms of the security and the indenture, but will be an amount less than the amount payable at the maturity of the principal of the original issue discount security.

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        If the subordinated debt securities are issued with "original issue discount" within the meaning of the Internal Revenue Code of 1986, as amended, then a holder of those subordinated debt securities will be required under the Internal Revenue Code to include original issue discount in ordinary income for federal income tax purposes as it accrues, in accordance with a constant interest method that takes into account the compounding of interest, in advance of receipt of cash attributable to that income. Generally, the total amount of original issue discount on a subordinated debt security will be the excess of the stated redemption price at maturity of the security over the price at which the security is sold to the public. To the extent a holder of a subordinated debt security receives a payment (at the time of acceleration of maturity, for example) that represents payment of original issue discount already included by the holder in ordinary income or reflected in the holder's tax basis in the security, that holder generally will not be required to include the payment in income. The specific terms of any subordinated debt securities that are issued with original issue discount and the application of the original discount rules under the Internal Revenue Code to those securities will be described in a prospectus supplement for those securities.

Registration and Transfer

        Unless otherwise indicated in the applicable prospectus supplement, subordinated debt securities will be issued only as registered securities. Subordinated debt securities issued as registered securities will not have interest coupons.

        Registered securities (other than a global security) may be presented for transfer, with the form of transfer endorsed thereon duly executed, or exchanged for other subordinated debt securities of the same series at the office of the security registrar specified in the indenture. The indenture provides that, with respect to registered securities having The City of New York as a place of payment, we will appoint a security registrar or co-security registrar located in The City of New York for such transfer or exchange. Transfer or exchange will be made without service charge, but we may require payment of any taxes or other governmental charges.

Book-Entry Subordinated Debt Securities

        Subordinated debt securities of a series may be issued in whole or in part in the form of one or more global securities. Each global security will be deposited with, or on behalf of, a depositary identified in the applicable prospectus supplement. Global securities will be issued in registered form and in either temporary or permanent form. Until exchanged in whole or in part for the individual securities which it represents, a global security may not be transferred except as a whole by the depositary for the global security to a nominee of the depositary or by a nominee of the depositary to the depositary or another nominee of the depositary or by the depositary or any nominee to a successor depositary or any nominee of the successor. The specific terms of the depositary arrangement for a series of subordinated debt securities will be described in the applicable prospectus supplement.

Payment and Paying Agents

        Unless otherwise indicated in an applicable prospectus supplement, payment of principal of and any premium and interest on registered securities will be made at the office of such paying agent or paying agents as we may designate from time to time. In addition, at our option, payment of any interest may be made by:

•

check mailed to the address of the person entitled to the payment at the address in the applicable security register; or



•

wire transfer to an account maintained by the person entitled to the payment as specified in the applicable security register.

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        Unless otherwise indicated in an applicable prospectus supplement, payment of any installment of interest on registered securities will be made to the person in whose name the subordinated debt security is registered at the close of business on the regular record date for the payment.

Subordination

        The subordinated debt securities will be subordinated and junior in right of payment to some of our other indebtedness (which may include senior indebtedness for money borrowed) to the extent described in the applicable prospectus supplement. At December 31, 2010, we had an aggregate amount of $1.2 billion of indebtedness that would be senior to any subordinated debt securities that we may issue.

Consolidation, Merger or Sale of Assets

        The indenture relating to the subordinated debt securities provides that we may, without the consent of the holders of any of the subordinated debt securities outstanding under the indenture, consolidate with, merge into or transfer our assets substantially as an entirety to any person, provided that:

•

any successor assumes our obligations on the subordinated debt securities and under the indenture; and



•

after giving effect to the consolidation, merger or transfer, no event of default (as defined in the indenture) will have happened and be continuing.

        Any consolidation, merger or transfer of assets substantially as an entirety, which meets the conditions described above, would not create an event of default which would entitle holders of the subordinated debt securities, or the trustee acting on their behalf, to take any of the actions described below under "—Events of Default, Waivers, Etc."

Leveraged and Other Transactions

        The indenture and the subordinated debt securities do not contain provisions which would protect holders of the subordinated debt securities in the event we engaged in a highly leveraged or other transaction which could adversely affect the holders of subordinated debt securities.

Modification of the Indenture

        The indenture provides that, with the consent of the holders of not less than a majority in aggregate principal amount of the outstanding subordinated debt securities of each affected series, modifications and alterations of the indenture may be made which affect the rights of the holders of the subordinated debt securities. However, no modification or alteration may be made without the consent of the holder of each subordinated debt security affected which would, among other things:

•

modify the terms of payment of principal of or any premium or interest on the subordinated debt securities;



•

adversely modify the subordination terms of the subordinated debt securities; or



•

reduce the percentage in principal amount of outstanding subordinated debt securities required to modify or alter the indenture.

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Events of Default, Waivers, Etc.

        An "event of default" with respect to subordinated debt securities of any series is defined in the indenture to include:

(1)

default in the payment of principal of or any premium on any of the outstanding subordinated debt securities of that series when due;



(2)

default in the payment of interest on any of the outstanding subordinated debt securities of that series when due and continuance of such default for 30 days;



(3)

default in the performance of any of our other covenants in the indenture with respect to the subordinated debt securities of that series and continuance of such default for 60 days after written notice;



(4)

certain events of bankruptcy, insolvency or reorganization relating to us; and



(5)

any other event that may be specified in a prospectus supplement with respect to any series of subordinated debt securities.

        If an event of default with respect to any series of outstanding subordinated debt securities occurs and is continuing, either the trustee or the holders of not less than 25% in aggregate principal amount of the outstanding subordinated debt securities of that series may declare the principal amount (or with respect to original issue discount securities, the portion of the principal amount as may be specified in the terms of that series) of all subordinated debt securities of that series to be immediately due and payable. The holders of a majority in aggregate principal amount of the outstanding subordinated debt securities of any series may waive an event of default resulting in acceleration of the subordinated debt securities, but only if all events of default with respect to subordinated debt securities of such series have been remedied and all payments due, other than those due as a result of acceleration, have been made.

        If an event of default occurs and is continuing, the trustee may, in its discretion, and at the written request of holders of not less than a majority in aggregate principal amount of the outstanding subordinated debt securities of any series and upon reasonable indemnity against the costs, expenses and liabilities to be incurred in compliance with such request and subject to certain other conditions set forth in the indenture will, proceed to protect the rights of the holders of all the subordinated debt securities of that series. Prior to acceleration of maturity of the outstanding subordinated debt securities of any series, the holders of a majority in aggregate principal amount of the subordinated debt securities may waive any past default under the indenture except a default in the payment of principal of or any premium or interest on the subordinated debt securities of that series.

        The indenture provides that upon the occurrence of an event of default specified in clauses (1) or (2) of the first paragraph in this subsection, we will, upon demand of the trustee, pay to it, for the benefit of the holders of any subordinated debt securities, the whole amount then due and payable on the affected subordinated debt securities for principal, premium, if any, and interest, if any. The indenture further provides that if we fail to pay such amount upon demand, the trustee may, among other things, institute a judicial proceeding for the collection of those amounts.

        The indenture also provides that notwithstanding any of its other provisions, the holder of any subordinated debt security of any series will have the right to institute suit for the enforcement of any payment of principal of or any premium or interest on the subordinated debt securities when due and that such right will not be impaired without the consent of that holder.

        We are required to file annually with the trustee a written statement of our officers as to the existence or non-existence of defaults under the indenture or the subordinated debt securities.

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Satisfaction and Discharge

        The indenture provides, among other things, that when all subordinated debt securities not previously delivered to the trustee for cancellation (1) have become due and payable or (2) will become due and payable at their stated maturity within one year, we may deposit with the trustee funds, in trust, for the purpose and in an amount sufficient to pay and discharge the entire indebtedness on the subordinated debt securities not previously delivered to the trustee for cancellation. Those funds will include all principal, premium, if any, and interest, if any, to the date of the deposit or to the stated maturity, as applicable. Upon such deposit, the indenture will cease to be of further effect except as to our obligations to pay all other sums due under the indenture and to provide the officers' certificates and opinions of counsel required under the indenture. At such time we will be deemed to have satisfied and discharged the indenture.

Governing Law

        The indenture and the subordinated debt securities will be governed by, and construed in accordance with, the laws of the State of New York.

Regarding the Trustee

        Information concerning the trustee for a series of subordinated debt securities will be set forth in the prospectus supplement relating to that series of subordinated debt securities.

        We may have normal banking relationships with the trustee in the ordinary course of business.

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DESCRIPTION OF CAPITAL STOCK

General

        Our authorized capital stock consists of 100,000,000 shares of common stock, par value $1.00 per share, and 25,000,000 shares of preferred stock, without par value. As of May 31, 2011, 39,417,320 shares of common stock and no shares of preferred stock were outstanding.

Common Stock

        The holders of our common stock are entitled to one vote for each share held of record on all matters submitted to a vote of shareholders. Holders may use cumulative voting for the election of directors. Subject to preferences that may be applicable to any outstanding series of preferred stock, holders of our common stock are entitled to receive equally dividends as they may be declared by our board of directors out of funds legally available for the payment of dividends. In the event of our liquidation or dissolution, holders of our common stock are entitled to share equally in all assets remaining after payment of liabilities and the liquidation preference of any outstanding series of preferred stock.

        Holders of our common stock have no preemptive rights and have no rights to convert their common stock into any other securities. All of the outstanding shares of our common stock are, and the shares of common stock we sell in any offering will be, duly authorized, validly issued, fully paid and nonassessable.

Preferred Stock

        Our board of directors has the authority, without further action by our shareholders, to issue shares of undesignated preferred stock from time to time in one or more series and to fix the related number of shares and the designations, voting powers, preferences, optional and other special rights, and restrictions or qualifications of that preferred stock. The particular terms of any series of preferred stock will be described in the prospectus supplement relating to that series of preferred stock. The rights, preferences, privileges and restrictions or qualifications of different series of preferred stock may differ from common stock and other series of preferred stock with respect to dividend rates, amounts payable on liquidation, voting rights, conversion rights, redemption provisions, sinking fund provisions and other matters. The issuance of additional series of preferred stock could:

•

decrease the amount of earnings and assets available for distribution to holders of common stock;



•

adversely affect the rights and powers, including voting rights, of holders of common stock; and



•

have the effect of delaying, deferring or preventing a change in control.

Depositary Shares

        We may issue fractional shares of preferred stock rather than full shares of preferred stock. If we exercise this option, we will issue receipts for depositary shares, and each of these depositary shares will represent a fraction (to be set forth in the prospectus supplement relating to such depositary shares) of a share of a particular series of preferred stock.

        The shares of any series of preferred stock underlying the depositary shares will be deposited under a deposit agreement between us and a bank or trust company selected by us. The depositary will have its principal office in the United States and a combined capital and surplus of at least $50,000,000. Subject to the terms of the deposit agreement, each owner of a depositary share will be entitled, in proportion to the applicable fraction of a share of preferred stock underlying the depositary share, to

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all of the rights and preferences of the preferred stock underlying that depositary share. Those rights may include dividend, voting, redemption, conversion and liquidation rights.

        The depositary shares will be evidenced by depositary receipts issued under a deposit agreement. Depositary receipts will be distributed to those persons purchasing the fractional shares of preferred stock underlying the depositary shares, in accordance with the terms of the offering. We will describe the material terms of the deposit agreement, the depositary shares and the depositary receipts in a prospectus supplement relating to the depositary shares. You should also refer to the forms of the deposit agreement and depositary receipts that will be filed with the SEC in connection with the offering of the specific depositary shares.

Anti-Takeover Effects of South Dakota Law and Provisions of Our Charter and Bylaws

        South Dakota law and our articles of incorporation and bylaws contain certain provisions that may be characterized as anti-takeover provisions. These provisions may make it more difficult to acquire control of us or remove our management.

Control Share Acquisitions

        The control share acquisition provisions of the South Dakota Domestic Public Corporation Takeover Act provide generally that the shares of a publicly held South Dakota corporation acquired by a person that exceed the thresholds of voting power described below will have the same voting rights as other shares of the same class or series only if approved by:

•

the affirmative vote of the majority of all outstanding shares entitled to vote, including all shares held by the acquiring person; and



•

the affirmative vote of the majority of all outstanding shares entitled to vote, excluding all interested shares.

Each time an acquiring person reaches a threshold, an election must be held as described above before the acquiring person will have any voting rights with respect to shares in excess of such threshold. The thresholds which require shareholder approval before voting powers are obtained with respect to shares acquired in excess of such thresholds are 20%, 33¹/3% and 50%, respectively. We have elected in our articles of incorporation not to be subject to these provisions of South Dakota law.

Business Combinations

        We are subject to the provisions of Section 47-33-17 of the South Dakota Domestic Public Corporation Takeover Act. In general, Section 47-33-17 prohibits a publicly held South Dakota corporation from engaging in a "business combination" with an "interested shareholder", unless the business combination or the transaction in which the person became an interested shareholder is approved in a prescribed manner. Unless the interested shareholder has been an interested shareholder for at least four years, a business combination with the interested shareholder must be approved by the board of directors of the corporation prior to the date of the interested shareholder's acquisition of the corporation's voting stock, by the affirmative vote of all of the holders of all of the outstanding voting shares, or, under some circumstances, by the affirmative vote of the holders of a majority of the outstanding voting shares exclusive of those shares beneficially owned by the interested shareholder or any of its affiliates or associates. After the four year period has elapsed, the business combination must still be approved, if not previously approved in the manner prescribed, by the affirmative vote of the holders of a majority of the outstanding voting shares exclusive, in some instances, of those shares beneficially owned by the interested shareholder or any of its affiliates or associates. Generally, an "interested shareholder" is a person who, together with affiliates and associates, beneficially owns, directly or indirectly, 10% or more of the corporation's voting stock. A "business combination" includes

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a merger, a transfer of 10% or more of the corporation's assets, the issuance or transfer of stock equal to 5% or more of the aggregate market value of all of the corporation's outstanding shares, the adoption of a plan of liquidation or dissolution, or other transaction resulting in a financial benefit to the interested shareholder. The provisions of Section 47-33-17 of the South Dakota Domestic Public Corporation Takeover Act may delay, defer or prevent a change in control of us without the shareholders taking further action.

        The South Dakota Domestic Public Corporation Takeover Act further provides that our board, in determining whether to approve a merger or other change of control, may take into account both the long-term as well as short-term interests of us and our shareholders, the effect on our employees, customers, creditors and suppliers, the effect upon the community in which we operate and the effect on the economy of the state and nation. This provision may permit our board to vote against some proposals that, in the absence of this provision, it would otherwise have a fiduciary duty to approve.

Fair Price Provision

        Our articles of incorporation require the affirmative vote of the holders of 80% or more of the outstanding shares of our voting stock to approve any "business transaction" with any "related person" or any "business transaction" in which a "related person" has an interest. However, if a majority of the members of our board who are not affiliated with the related party approve the business transaction, or if the cash or fair market value of any consideration received by our shareholders pursuant to a business transaction meets certain enumerated requirements, then the 80% voting requirement will not be applicable. Generally, our articles of incorporation define a "business transaction" to include a merger, asset or stock sale. Our articles of incorporation generally define a "related person" as any person or entity that, together with its affiliates and associates, beneficially owns 10% or more of our outstanding voting stock. The likely effect of this provision is to delay, defer or prevent a change in control.

Board Composition

        Our articles of incorporation and bylaws provide for a staggered board of directors divided into three classes, with the term of office of one class expiring each year. Our articles of incorporation and bylaws also provide that our directors may be removed only for cause and by the affirmative vote of the majority of the remaining members of the board of directors. The likely effect of our staggered board of directors and the limitation on the removal of directors is an increase in the time required for the shareholders to change the composition of our board of directors.

Authorized but Unissued Shares

        The authorized but unissued shares of our common stock and preferred stock are available for future issuance without shareholder approval. These additional shares may be used for a variety of corporate purposes, including future public offerings to raise additional capital, corporate acquisitions and employee benefit plans. The existence of authorized but unissued and unreserved common stock and preferred stock could also render more difficult or discourage an attempt to obtain control of us by means of a proxy contest, tender offer, merger or otherwise.

        Our board of directors has no present intention to issue any new series of preferred stock; however, our board has the authority, without further shareholder approval, to issue one or more series of preferred stock that could, depending on the terms of the series, either impede or facilitate the completion of a merger, tender offer or other takeover attempt. Although our board of directors is required to make any determination to issue such stock based on its judgment as to the best interest of our shareholders, our board could act in a manner that would discourage an acquisition attempt or other transaction that some, or a majority, of the shareholders might believe to be in their best

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interests or in which shareholders might receive a premium for their stock over the then market price of such stock. Our board of directors does not intend to seek shareholder approval prior to any issuance of stock, unless otherwise required by law or the rules of the stock exchange on which our common stock is listed.

Shareholder Action by Written Consent Must Be Unanimous

        South Dakota law provides that any action which may be taken at a meeting of shareholders may be taken without a meeting if a written consent, setting forth the action taken, is signed by all of the shareholders entitled to vote with respect to the action taken. This provision prevents holders of less than all of our common stock from unilaterally using the written consent procedure to take shareholder action.

Transfer Agent

        The transfer agent and registrar for our common stock is Wells Fargo Shareowner Services. Its address is P.O. Box 64856, St. Paul, Minnesota 55164-0856, and its telephone number for shareholder services is (800) 468-9716.

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DESCRIPTION OF WARRANTS

Offered Warrants

        We may issue warrants that are debt warrants or equity warrants. We may offer warrants separately or together with one or more additional warrants or debt or equity securities or any combination of those securities in the form of units, as described in the applicable prospectus supplement. If we issue warrants as part of a unit, the accompanying prospectus supplement will specify whether those warrants may be separated from the other securities in the unit prior to the warrants' expiration date.

Debt Warrants

        We may issue, together with debt securities or separately, warrants for the purchase of debt securities on terms to be determined at the time of sale.

Equity Warrants

        We may also issue, together with equity securities or separately, warrants to purchase, including warrant spreads, shares of our common or preferred stock on terms to be determined at the time of sale.

General Terms of Warrants

        The applicable prospectus supplement will contain, where applicable, the following terms of and other information relating to the warrants and warrant spreads:

•

the specific designation and aggregate number of, and the price at which we will issue, the warrants;



•

the currency with which the warrants may be purchased;



•

the date on which the right to exercise the warrants will begin and the date on which that right will expire or, if you may not continuously exercise the warrants throughout that period, the specific date or dates on which you may exercise the warrants;



•

whether the warrants will be issued in fully registered form or bearer form, in definitive or global form or in any combination of these forms, although, in any case, the form of a warrant included in a unit will correspond to the form of the unit and of any debt security included in that unit;



•

any applicable material United States federal income tax consequences;



•

the identity of the warrant agent for the warrants and of any other depositaries, execution or paying agents, transfer agents, registrars, determination agents or other agents;



•

the proposed listing, if any, of the warrants or any securities purchasable upon exercise of the warrants on any securities exchange;



•

if applicable, the minimum or maximum amount of the warrants that may be exercised at any one time;



•

information with respect to book-entry procedures, if any;



•

the terms of the securities issuable upon exercise of the warrants;



•

the antidilution provisions of the warrants, if any;



•

any redemption or call provisions;



•

the exercise price and procedures for exercise of the warrants;

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•

the terms of any warrant spread and the market price of our common stock which will trigger our obligation to issue shares of our common stock in settlement of a warrant spread;



•

whether the warrants are to be sold separately or with other securities as part of units; and



•

any other terms of the warrants.

Significant Provisions of the Warrant Agreements

        We will issue the warrants under one or more warrant agreements to be entered into between us and a bank or trust company, as warrant agent, in one or more series, which will be described in the prospectus supplement for the warrants. The following summaries of significant provisions of the warrant agreements and the warrants are not intended to be comprehensive, and holders of warrants should review the detailed description of the relevant warrant agreement included in any prospectus supplement.

Modifications Without Consent of Warrantholders

        We and the warrant agent may amend the terms of the warrants and the warrant certificates without the consent of the holders to:

•

cure any ambiguity;



•

cure, correct or supplement any defective or inconsistent provision; or



•

amend the terms in any other manner which we may deem necessary or desirable and which will not adversely affect the interests of the affected holders in any material respect.

Enforceability of Rights of Warrantholders

        The warrant agents will act solely as our agents in connection with the warrant certificates and will not assume any obligation or relationship of agency or trust for or with any holders of warrant certificates or beneficial owners of warrants. Any holder of warrant certificates and any beneficial owner of warrants may, without the consent of any other person, enforce by appropriate legal action, on its own behalf, its right to exercise the warrants evidenced by the warrant certificates in the manner provided for in that series of warrants or pursuant to the applicable warrant agreement. No holder of any warrant certificate or beneficial owner of any warrants will be entitled to any of the rights of a holder of the debt securities or any other warrant property, if any, purchasable upon exercise of the warrants, including, without limitation, the right to receive the payments on those debt securities or other warrant property or to enforce any of the covenants or rights in the relevant indenture or any other similar agreement.

Registration and Transfer of Warrants

        Subject to the terms of the applicable warrant agreement, warrants in registered, definitive form may be presented for exchange and for registration of transfer at the corporate trust office of the warrant agent for that series of warrants, or at any other office indicated in the prospectus supplement relating to that series of warrants, without service charge. However, the holder will be required to pay any taxes and other governmental charges as described in the warrant agreement. The transfer or exchange will be effected only if the warrant agent for the series of warrants is satisfied with the documents of title and identity of the person making the request.

New York Law to Govern

        The warrants and each warrant agreement will be governed by, and construed in accordance with, the laws of the State of New York.

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DESCRIPTION OF PURCHASE CONTRACTS

        We may issue purchase contracts, including contracts obligating holders to purchase from us and us to sell to the holders, a specified principal amount of debt securities or a specified number of shares of common stock or preferred stock or any of the other securities that we may sell under this prospectus (or a range of principal amount or number of shares pursuant to a predetermined formula) at a future date or dates. The consideration payable upon settlement of the purchase contracts may be fixed at the time the purchase contracts are issued or may be determined by a specific reference to a formula set forth in the purchase contracts. The purchase contracts may be issued separately or as part of units consisting of a purchase contract and other securities or obligations issued by us or third parties, including United States treasury securities, securing the holders' obligations to purchase the relevant securities under the purchase contracts. The purchase contracts may require us to make periodic payments to the holders of the purchase contracts or units or vice versa, and the payments may be unsecured or prefunded on some basis. The purchase contracts may require holders to secure their obligations under the purchase contracts in a specified manner and in some circumstances we may deliver newly issued prepaid purchase contracts, often referred to as "prepaid securities," upon release to a holder of any collateral securing such holder's obligations under the original purchase contract.

        The applicable prospectus supplement will describe the terms of any purchase contracts or purchase units and, if applicable, such other securities or obligations. The description in the prospectus supplement will not necessarily be complete and will be qualified in its entirety by reference to the purchase contracts, and, if applicable, collateral arrangements, relating to the purchase contracts.

DESCRIPTION OF UNITS

        We may issue units consisting of one or more purchase contracts, warrants, debt securities, shares of preferred stock, shares of common stock or any combination of such securities. The applicable prospectus supplement will describe:

•

the terms of the units and of the purchase contracts, warrants, debt securities, preferred stock and/or common stock comprising the units, including whether and under what circumstances the securities comprising the units may be traded separately;



•

a description of the terms of any unit agreement governing the units; and



•

a description of the provisions for the payment, settlement, transfer or exchange of the units.

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PLAN OF DISTRIBUTION

        From time to time, we may sell the securities offered by this prospectus:

•

through underwriters or dealers;



•

through agents;



•

directly to purchasers; or



•

through a combination of any of these methods of sale.

        This prospectus may be used in connection with any offering of our securities through any of these methods or other methods described in the applicable prospectus supplement. Any underwriter, dealer or agent may be deemed to be an "underwriter" within the meaning of the Securities Act of 1933.

        The applicable prospectus supplement relating to the securities will set forth:

•

their offering terms, including the name or names of any underwriters, dealers or agents;



•

the purchase price of the securities and the net proceeds we may receive from the sale;



•

any underwriting discounts, fees, commissions and other items constituting compensation to underwriters, dealers or agents;



•

any initial public offering price;



•

any discounts, commissions or concessions allowed or reallowed or paid by underwriters or dealers to other dealers; and



•

any securities exchanges on which the securities may be listed.

        If underwriters or dealers are used in the sale, the securities will be acquired by the underwriters or dealers for their own account and may be resold from time to time in one or more transactions:

•

at a fixed price or prices which may be changed;



•

at market prices prevailing at the time of sale;



•

at prices related to such prevailing market prices; or



•

at negotiated prices.

        The securities may be offered to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more of such firms. Unless otherwise set forth in the applicable prospectus supplement, the obligations of underwriters or dealers to purchase the offered securities will be subject to certain conditions precedent, and the underwriters or dealers will be obligated to purchase all the offered securities if any are purchased. Any public offering price and any discounts or concessions allowed or reallowed or paid by underwriters or dealers to other dealers may be changed from time to time.

        Securities may be sold directly by us or through agents designated by us from time to time. Any agent involved in the offer or sale of the securities in respect of which this prospectus is delivered will be named, and any commissions payable by us to the agent will be set forth, in the applicable prospectus supplement. Unless otherwise indicated in the applicable prospectus supplement, any such agent will be acting on a best efforts basis for the period of its appointment.

        If so indicated in the applicable prospectus supplement, we will authorize underwriters, dealers or agents to solicit offers from certain specified institutions to purchase securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. Such contracts will be subject to any

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conditions set forth in the applicable prospectus supplement and the prospectus supplement will set forth the commission payable for solicitation of such contracts. The underwriters and other persons soliciting such contracts will have no responsibility for the validity or performance of any such contracts.

        Underwriters, dealers and agents may be entitled under agreements entered into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act of 1933, or to contribution by us to payments which they may be required to make. Underwriters, dealers and agents may be customers of, engage in transactions with, or perform services for, us in the ordinary course of business.

        Each class or series of securities will be a new issue of securities with no established trading market, other than our common stock, which is listed on the New York Stock Exchange. We may elect to list any other class or series of securities on any exchange, but are not obligated to do so. Any underwriters to whom securities are sold by us for public offering and sale may make a market in such securities, but such underwriters will not be obligated to do so and may discontinue any market making at any time without notice. No assurance can be given as to the liquidity of the trading market for any securities.

LEGAL OPINIONS

        The validity of the securities offered by this prospectus will be passed upon for Black Hills Corporation by Steven J. Helmers, Senior Vice President-General Counsel of Black Hills, with respect to matters governed by South Dakota law, and by Faegre & Benson LLP, Denver, Colorado, special counsel to Black Hills, with respect to matters governed by New York law. Certain legal matters will be passed upon for Black Hills by Faegre & Benson LLP, Denver, Colorado, and for the underwriters, dealers, or agents, if any, by their own legal counsel. Mr. Helmers owns, directly or indirectly, 41,044 shares of our common stock, and holds options to purchase an additional 10,110 shares.

EXPERTS

        The financial statements, and the related financial statement schedules, incorporated in this prospectus by reference from the Company's Annual Report on Form 10-K, and the effectiveness of Black Hills Corporation's internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports (which reports (1) express an unqualified opinion on the financial statements and financial statement schedules and includes an explanatory paragraph referring to the adoption of a new accounting standard and (2) express an unqualified opinion on the effectiveness of internal control over financial reporting), which are incorporated herein by reference. Such financial statements and financial statement schedules have been so incorporated in reliance upon the reports of such firm given upon their authority as experts in accounting and auditing.

        We have derived the estimates of proved oil and natural gas reserves and related future net revenues and the present value thereof as of December 31, 2010 included in our Annual Report on Form 10-K for the year ended December 31, 2010 and incorporated by reference in this prospectus from the reserve report of Cawley, Gillespie & Associates, Inc., independent petroleum engineers, given on the authority of Cawley, Gillespie & Associates, Inc. as experts in such matters.

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WHERE YOU CAN FIND MORE INFORMATION

        This prospectus constitutes a part of a registration statement on Form S-3 (together with all amendments, supplements, schedules and exhibits to the registration statement, referred to as the registration statement) that we have filed with the SEC under the Securities Act of 1933 with respect to the securities offered by this prospectus. This prospectus does not contain all the information which is in the registration statement. Certain parts of the registration statement are omitted as allowed by the rules and regulations of the SEC. We refer you to the registration statement for further information about our company and the securities offered by this prospectus. Statements contained in this prospectus concerning the provisions of documents are not necessarily complete, and each statement is qualified in its entirety by reference to the copy of the applicable document filed with the SEC.

        We also file annual, quarterly and special reports, proxy statements and other information with the SEC. You can inspect and copy the registration statement and the reports and other information we file with the SEC at the public reference room maintained by the SEC at 100 F Street, N.E., Washington, D.C. 20549, at prescribed rates. You can obtain information on the operation of the public reference room by calling the SEC at 1-800-SEC-0330. The SEC also maintains an Internet website which provides online access to reports, proxy and information statements and other information regarding companies that file electronically with the SEC at the address http://www.sec.gov.

        The SEC allows us to "incorporate by reference" into this prospectus the information we file with them, which means we can disclose important business and financial information about us to you by referring you to those documents. The information incorporated by reference is considered to be a part of this prospectus, except for any information that is superseded by information included directly in this prospectus and any prospectus supplement. Information that we file later with the SEC will also automatically update and supersede the information in this prospectus. We incorporate by reference the documents listed below that we previously filed with the SEC (SEC File No. 1-31303) and any future filings we make with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934 (other than any portions of such filings that are furnished rather than filed under applicable SEC rules) until the termination of the offering made under this prospectus:

•

Our Annual Report on Form 10-K for the fiscal year ended December 31, 2010;



•

Our Quarterly Report on Form 10-Q for the quarter ended March 31, 2011;



•

Our Current Report on Form 8-K filed on May 31, 2011; and



•

The description of our common stock contained in our registration statement on Form 8-A, dated April 19, 2002, including any amendment or report filed before or after the date of this prospectus for the purpose of updating the description.

        These filings have not been included in or delivered with this prospectus. We will provide to each person, including any beneficial owner to whom this prospectus is delivered, a copy of any or all information that has been incorporated by reference in this prospectus but not delivered with this prospectus. You may obtain a copy of these filings, at no cost, from our Internet website (www.blackhillscorp.com) or by writing or telephoning us at the following address:

Black Hills Corporation
625 Ninth Street
Rapid City, South Dakota 57701
Attention: Investor Relations
(605) 721-1700

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.    Other Expenses of Issuance and Distribution.

        The following is an estimate, subject to future contingencies, of the expenses to be incurred by the Registrant in connection with the issuance and distribution of the securities being registered:

Item 15.    Indemnification of Directors and Officers.

        Section 47-1A-851 of the South Dakota Codified Laws allows a corporation to indemnify any person who was, is, or is threatened to be made a defendant or respondent to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative, arbitrative or investigative and whether formal or informal, by reason of the fact that he is or was a director or officer of the corporation, or is or was serving at the request of the corporation as a director, officer, partner, trustee, employee or agent of another corporation, partnership, joint venture, trust, employee benefit plan or other entity, against judgments, settlements, penalties, fines and reasonable expenses (including attorneys' fees) incurred by that person in connection with such action, suit or proceeding if that person acted in good faith and in a manner that person reasonably believed to be, in the case of conduct in an official capacity, in the best interests of the corporation, and in all other cases, at least not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe such conduct was unlawful. Unless ordered by a court, the corporation may not indemnify a director (a) in respect of a proceeding by or in the right of the corporation, except for reasonable expenses incurred in connection with the proceeding if it is determined that the director has met the relevant standard of conduct in Section 47-1A-851, or (b) in connection with any proceeding with respect to conduct for which the director was adjudged liable on the basis that the director received a financial benefit to which the director was not entitled, whether or not involving action in the director's official capacity.

        Our Bylaws provide that we shall indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, including all appeals, by reason of the fact that such person is or was serving or has agreed to serve as a director or officer of us or at our request of another corporation or entity, who acted in good faith and in a manner which such person reasonably believed to be within the scope of such person's authority and in, or not opposed to, our best interests, and, with respect to any criminal action or proceeding, the person had no reasonable cause to believe their conduct was unlawful, against liability incurred by such person in connection with the defense or settlement of such action or suit and any appeal therefrom. With respect to proceedings by or in our right to procure judgment in our favor, no indemnification shall be made in respect of any claim, issue or matter as to which such person shall have been adjudged to be liable to us unless and only to the extent that the court in which such action or suit was brought shall

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determine that, despite the adjudication of such liability but in view of all the circumstances of the case, such person is fairly and reasonably entitled to indemnity. In addition, we have entered into specific agreements with our directors and officers providing for indemnification of such persons under certain circumstances.

        Our Articles of Incorporation also eliminate the personal liability of our directors for monetary damages for breach of their fiduciary duty as directors. This provision, however, does not eliminate a director's liability (a) for any breach of the director's duty of loyalty to us or our shareholders, (b) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (c) for unlawful distributions by directors in violation of the South Dakota Codified Laws, or (d) for any transaction for which the director received an improper personal benefit.

        We carry directors' and officers' liability insurance to insure our directors and officers against liability for certain errors and omissions and to defray costs of a suit or proceeding against an officer or director.

Item 16.    Exhibits.

        The exhibits to this registration statement are listed on the Exhibit Index to this registration statement, which Exhibit Index is hereby incorporated by reference.

Item 17.    Undertakings.

        (a)   The undersigned Registrant hereby undertakes:

        (1)   To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

          (i)  To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

         (ii)  To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement;

        (iii)  To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the Registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

        (2)   That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

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        (3)   To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

        (4)   That, for purposes of determining liability under the Securities Act of 1933 to any purchaser:

        (A)  Each prospectus filed by the Registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

        (B)  Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5) or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii) or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which the prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

        (5)   That, for purposes of determining liability of the Registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the undersigned Registrant undertakes that in a primary offering of securities of the undersigned Registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned Registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

          (i)  Any preliminary prospectus or prospectus of the undersigned Registrant relating to the offering required to be filed pursuant to Rule 424;

         (ii)  Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned Registrant or used or referred to by the undersigned Registrant;

        (iii)  The portion of any other free writing prospectus relating to the offering containing material information about the undersigned Registrant or its securities provided by or on behalf of the undersigned Registrant; and

        (iv)  Any other communication that is an offer in the offering made by the undersigned Registrant to the purchaser.

        (b)   The undersigned Registrant hereby undertakes, that, for purposes of determining any liability under the Securities Act of 1933, each filing of the Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

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        (c)   Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

        (d)   The undersigned Registrant hereby undertakes to file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of Section 310 of the Trust Indenture Act in accordance with the rules and regulations prescribed by the Commission under Section 305(b)(2) of the Trust Indenture Act.

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SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Rapid City, State of South Dakota, on June 20, 2011.

        Each of the undersigned officers and directors of Black Hills Corporation, a South Dakota corporation, hereby constitutes and appoints David R. Emery and Steven J. Helmers, and each of them, as his or her true and lawful attorney-in-fact and agent, severally, with full power of substitution and resubstitution, in his or her name and on his or her behalf, in any and all capacities, to sign any and all amendments (including post-effective amendments and supplements) to this Registration Statement, and to file the same with all exhibits thereto and all documents in connection therewith, with the SEC, granting unto said attorneys-in-fact and agents, and each of them full power and authority to do and perform each and every act and thing necessary or appropriate to be done with respect to this Registration Statement or any amendments or supplements hereto in and about the premises, as fully to all intents and purposes as he or she might or could do in person, thereby ratifying and confirming all that said attorneys-in-fact and agents, or their substitute or substitutes, may lawfully do or cause to be done.

        Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

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INDEX TO EXHIBITS

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