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





                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                    FORM 11-K


                                  ANNUAL REPORT
                        PURSUANT TO SECTION 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934


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


                   For the fiscal year ended December 31, 1999


                          Commission File Number 1-7978


                             BLACK HILLS CORPORATION
                          EMPLOYEE STOCK PURCHASE PLAN


                             BLACK HILLS CORPORATION
                                625 NINTH STREET
                                   PO BOX 1400
                         RAPID CITY, SOUTH DAKOTA 57709



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



<PAGE>






                             BLACK HILLS CORPORATION
                          EMPLOYEE STOCK PURCHASE PLAN










                              FINANCIAL STATEMENTS
                        AS OF DECEMBER 31, 1999 AND 1998
                             TOGETHER WITH REPORT OF
                         INDEPENDENT PUBLIC ACCOUNTANTS


<PAGE>


                    REPORT OF INDEPENDENT PUBLIC ACCOUNTANTS




To the Employee Stock Purchase Plan
Committee of the Black Hills Corporation
Employee Stock Purchase Plan:

We have audited the accompanying  statements of financial  position of the Black
Hills  Corporation  Employee  Stock  Purchase Plan (the Plan) as of December 31,
1999 and 1998, and the related statements of income and changes in participants'
equity for each of the three years in the period ended December 31, 1999.  These
financial  statements are the responsibility of the Employee Stock Purchase Plan
Committee  and the Company's  management.  Our  responsibility  is to express an
opinion on these financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable  assurance about whether the financial  statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting  the amounts and  disclosures in the financial  statements.  An audit
also includes assessing the accounting principles used and significant estimates
made by  management,  as well as  evaluating  the  overall  financial  statement
presentation.  We believe  that our audits  provide a  reasonable  basis for our
opinion.

In our opinion,  the financial  statements  referred to above present fairly, in
all material  respects,  the  financial  position of the Plan as of December 31,
1999 and 1998,  and the income and changes in  participants'  equity for each of
the three years in the period  ended  December  31,  1999,  in  conformity  with
accounting principles generally accepted in the United States.




Minneapolis, Minnesota                                      Arthur Andersen LLP
January 26, 2000




<PAGE>


                             Black Hills Corporation
                          Employee Stock Purchase Plan
                        Statements of Financial Position
                                   December 31

                                                     1999            1998
                                                     ----            ----
Assets

   Cash                                            $77,457          $95,392
                                                   =======          =======

Liabilities and Participants' Equity

   Participants' Equity                            $77,457          $95,392
                                                   =======          =======


The accompanying note is an integral part of these statements.


<PAGE>


                             Black Hills Corporation
                          Employee Stock Purchase Plan
            Statements of Income and Changes in Participants' Equity
                            For the years December 31


                                          1999            1998          1997
                                          ----            ----          ----

Participants' Equity, Beginning of Year $  95,392      $  43,582     $  81,332

Increases (Decreases) During the Year:
   Employee Contributions Received        396,659        269,719       359,188
   Dividend Income                          9,184          5,314        11,804
   Distributions to Participants         (423,778)      (223,223)     (408,742)
                                        ---------      ---------      ---------

Participants' Equity, End of Year       $  77,457      $  95,392      $  43,582
                                        =========      =========      =========


The accompanying note is an integral part of these statements.



<PAGE>


                             Black Hills Corporation
                          Employee Stock Purchase Plan
                          Note to Financial Statements
                                December 31, 1999

(1)      Plan Description

         General - The Black Hills Corporation Employee Stock Purchase Plan (the
         Plan) was adopted by the Board of Directors of Black Hills  Corporation
         (the  Company)  on January 29,  1987,  and  approved  by the  Company's
         stockholders  on May 20,  1987,  at which  time  100,000  shares of the
         Company's  Common Stock were  reserved for offering  under the Plan. At
         the  May  23,  1995  Annual  Meeting  of  Shareholders,  the  Company's
         stockholders  approved an  additional  200,000  shares of the Company's
         Common  Stock,  for issuance  under the Plan.  As of December 31, 1999,
         247,570 shares were available for issuance under the Plan.

         The Board of Directors of the Company  determine the "Offering Date" on
         which shares of the  Company's  common stock may be offered.  Offerings
         under the Plan may be made at such times, for such number of shares and
         remain open for such periods (up to 90 days) as the Company's  Board of
         Directors may prescribe.  Subscriptions can only be accepted during the
         prescribed  period.  The  subscription  price  per share is equal to 90
         percent of the fair market  value of the Common  Stock on the  offering
         date and is set forth in the Subscription Agreement.

         Administration  - The Plan is administered by the Board of Directors of
         the Company who have the power and authority to  promulgate  such rules
         and regulations as they deem appropriate for the  administration of the
         Plan, to interpret its provisions and to take all actions in connection
         therewith  as they  deem  necessary  or  advisable.  Other  aspects  of
         administration   are  handled  by  the  Employee  Stock  Purchase  Plan
         Committee, the members of which are designated from time to time by the
         Chief  Executive   Officer  of  the  Company.   The  Company  pays  all
         administrative costs of the Plan.

         Eligibility and Vesting - Each full-time employee of the Company or its
         subsidiaries,  including officers,  but excluding directors who are not
         employees of the Company or subsidiaries, is eligible to participate in
         the Plan. A full-time  employee is one who is in the active  service of
         the Company or its  subsidiaries  on the date an offering is made.  Any
         employee whose customary employment is twenty hours or less per week or
         whose  customary  employment  is for not  more  than  five  months  per
         calendar year is not eligible to participate.

         No employee  is allowed to  participate  in the Plan if such  employee,
         immediately  after the  offering is granted,  owns stock  possessing  5
         percent  or more of the  total  combined  voting  power or value of all
         classes of stock of the Company.

         Employees are immediately vested.

<PAGE>

         Contributions - The plan is solely funded by participant contributions.
         An eligible  employee may  subscribe for not less than 20 nor more than
         400  shares  of  Common  Stock in  connection  with  each  offering.  A
         subscription  must be  accompanied  by an initial  payment of $1.00 for
         each share of stock for which a  subscription  is made.  The  remaining
         balance will be paid through  equal  payroll  deductions  during the 12
         month period following the Subscription Date.

         Investment of Funds;  Issuance of Shares - Amounts paid by participants
         on the Plan subscriptions through payroll deductions are applied solely
         to purchase  shares of Common Stock  allotted to them,  pursuant to the
         Plan.

         Except in the event of withdrawal  or  cancellation,  certificates  for
         shares  subscribed  to  pursuant  to an  offering  are not issued to an
         employee until all shares have been paid for in full.

         Dividends - Dividends  are applied  toward the  purchase of  additional
         shares of common stock of the Company through the Dividend Reinvestment
         and Stock Purchase Plan at the offering price.

         Withdrawal  From the Plan or  Cancellation of Subscription - Shares are
         distributed to employees after the subscription is paid for in full.

         An employee  participating in the Plan has the right, any time prior to
         payment in full, to cancel a  subscription  for unpaid shares by giving
         the committee  written  notice to that effect.  Upon payment in full of
         the  subscription  or upon  withdrawal  from the Plan or termination of
         employment,  the  participant's  account  will be cleared by one of the
         following  methods pursuant to the  participant's  request;  (a) shares
         transferred to employee's "of record" account;  (b) certificate  issued
         for whole shares and a check for fractional  shares; or (c) shares sold
         on the open market.

         Termination of employment for any reason including retirement or death,
         accompanied  by  failure  of  the  terminated  employee  or  the  legal
         representative  of the descendent to pay the entire balance due for the
         purchase of the shares for which a subscription  has been accepted will
         result in cancellation.  Such election shall be made within ten days of
         the time of termination of employment,  except for death which shall be
         within two months following death.



<PAGE>


                                    SIGNATURE


Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
Employee  Stock Purchase Plan Committee has duly caused this Annual Report to be
signed on its behalf by the undersigned hereunto duly authorized.



                                             Black Hills Corporation
                                             Employee Stock Purchase Plan


Date:  March 10, 2000                     By _________________________________
                                             Roxann R. Basham


<PAGE>


                    CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS


As independent public accountants, we hereby consent to the incorporation of our
report dated  January 26, 2000,  included in this Form 11-K,  into the Company's
previously filed Registration Statement (Form S-8 No. 33-63059).




                                                   ARTHUR ANDERSEN LLP


Minneapolis, Minnesota
March 10, 2000