<PAGE>   1
                                    FORM 10-Q

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

(X)  QUARTERLY REPORT UNDER SECTION 13 OR 15 (d) OF THE SECURITIES
     EXCHANGE ACT OF 1934

For Quarter Ended  March 31, 2001
                   --------------

                                       or

(  ) TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE SECURITIES
     EXCHANGE ACT OF 1934


For the transition period from                        to
                               ----------------------    ---------------------


Commission File Number 2-39895
                       -------


                            MIDLAND ENTERPRISES INC.
             ------------------------------------------------------
             (Exact name of registrant as specified in its charter)


           DELAWARE                                            04-2284434
  -------------------------------                          -------------------
  (State or other jurisdiction of                           (I.R.S. Employer
  incorporation or organization)                           Identification No.)

   300 PIKE STREET, CINCINNATI, OHIO                              45202
----------------------------------------                        ----------
(Address of principal executive offices)                        (Zip code)

Registrant's telephone number, including area code           513-721-4000
                                                   ----------------------------


--------------------------------------------------------------------------------
              (Former    name, former address and former fiscal year, if changed
                         since last report.)

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                 Yes  X       No
                                    -----       -----

The number of shares of common stock of Midland Enterprises Inc. outstanding as
of the date of this report was 15 1/2, all held by Eastern Enterprises.

Registrant meets the conditions set forth in general instructions H(1) (a) and
(b) of Form 10-Q and is therefore filing this form with the reduced disclosure
format.


<PAGE>   2
                                                                              1

                    MIDLAND ENTERPRISES INC. AND SUBSIDIARIES

                       CONSOLIDATED STATEMENTS OF EARNINGS


<TABLE>
<CAPTION>
                                                             (000 OMITTED)
                                                        --------------------------
                                                        For the Three Months Ended
                                                        March 31,        March 31,
                                                          2001             2000
                                                        --------         --------
                                                                      (Predecessor)
<S>                                                    <C>              <C>
Revenues                                                $ 67,586         $ 71,270
                                                        --------         --------

OPERATING COSTS AND EXPENSES:
      Operating expenses                                $ 51,179         $ 53,920
      Depreciation and amortization                        5,828            6,132
      Goodwill amortization                                  525               --
      Selling, general & administrative expenses           3,254            3,324
      Overhead allocation from Parent                        795              700
      Taxes, other than income                             3,802            4,119
                                                        --------         --------
                                                        $ 65,383         $ 68,195
                                                        --------         --------

OPERATING EARNINGS                                      $  2,203         $  3,075
                                                        --------         --------

OTHER INCOME (EXPENSE):
      Interest income from Parent                       $  1,202         $    925
      Interest income other                                  212                9
      Other, net                                             (88)             (52)
                                                        --------         --------
                                                        $  1,326         $    882
                                                        --------         --------

INTEREST EXPENSE:
      Long-term debt                                    $  2,990         $  3,110
      Other, including amortization of
           debt expense                                       74               65
                                                        --------         --------
                                                        $  3,064         $  3,175
                                                        --------         --------

Earnings before income taxes                            $    465         $    782

Provision for Income taxes                                   416              392
                                                        --------         --------

NET EARNINGS                                            $     49         $    390
                                                        ========         ========
</TABLE>


                     The accompanying notes are an integral
                      part of these financial statements.
<PAGE>   3
                                                                               2

                    MIDLAND ENTERPRISES INC. AND SUBSIDIARIES

                           CONSOLIDATED BALANCE SHEETS



<TABLE>
<CAPTION>
                                                           (000 OMITTED)
                                             -------------------------------------------
                                              March 31,       Dec. 31,        March 31,
                                                2001            2000            2000
                                              ---------       --------        ---------
                                                                           (Predecessor)
<S>                                          <C>             <C>             <C>
ASSETS

CURRENT ASSETS:
         Cash and cash equivalents            $ 20,039        $ 11,178        $     86
         Receivables -
                 Trade, net                     15,871          13,445          19,537
                 Parent                         73,007          73,016          72,373
                 Other                             999           1,446           1,581
         Materials, supplies & fuel              8,524           8,945           9,224
         Prepaid expenses                        1,021           1,824           1,914
                                              --------        --------        --------

TOTAL CURRENT ASSETS                          $119,461        $109,854        $104,715
                                              --------        --------        --------


PROPERTY AND EQUIPMENT, AT COST               $337,882        $332,202        $679,807
         Less-accumulated depreciation           9,721           3,880         363,121
                                              --------        --------        --------

NET PROPERTY AND EQUIPMENT                    $328,161        $328,322        $316,686
                                              --------        --------        --------


OTHER ASSETS:
         Deferred pension charges             $ 13,871        $ 13,871        $ 16,698
         Goodwill, net (2)                      60,956          59,651              --
         Other                                   1,406           8,337           5,534
                                              --------        --------        --------

TOTAL OTHER ASSETS                            $ 76,233        $ 81,859        $ 22,232
                                              --------        --------        --------


TOTAL ASSETS                                  $523,855        $520,035        $443,633
                                              ========        ========        ========
</TABLE>



                     The accompanying notes are an integral
                      part of these financial statements.
<PAGE>   4
                                                                               3



                    MIDLAND ENTERPRISES INC. AND SUBSIDIARIES

                           CONSOLIDATED BALANCE SHEETS


<TABLE>
<CAPTION>
                                                                    (000 OMITTED)
                                                    ---------------------------------------------
                                                    March 31,          Dec. 31,         March 31,
                                                      2001              2000              2000
                                                    ---------         ---------         ---------
                                                                                      (Predecessor)
<S>                                                <C>               <C>               <C>
LIABILITIES AND STOCKHOLDER'S EQUITY

CURRENT LIABILITIES:
         Current portion of long - term debt        $   3,687         $   3,980         $   4,974
         Accounts payable trade                        12,999            11,161            12,390
         Reserve for insurance claims                   9,756             9,367            10,371
         Interest payable                               5,643             2,974             5,795
         Taxes payable                                  4,682             4,038             3,899
         Accrued expenses                               4,325             4,280             3,732
         Reserve for separation payments (3)              548             3,654                --
         Other current liabilities                     16,744            14,624             7,464
                                                    ---------         ---------         ---------

TOTAL CURRENT LIABILITIES                           $  58,384         $  54,078         $  48,625
                                                    ---------         ---------         ---------

LONG-TERM DEBT                                      $ 138,136         $ 138,819         $ 141,447
                                                    ---------         ---------         ---------

RESERVES AND DEFERRED CREDITS:
         Deferred income taxes                      $  77,176         $  77,141         $  71,303
         Unamortized investment tax credits             1,441             1,486             1,690
         Post-retirement health care                   19,105            19,092             9,370
         Other reserves                                 5,523             5,378             3,042
                                                    ---------         ---------         ---------

TOTAL RESERVES AND DEFERRED CREDITS                 $ 103,245         $ 103,097         $  85,405
                                                    ---------         ---------         ---------

STOCKHOLDER'S EQUITY:
         Common stock, $100 par value -
            Authorized shares - 1,000
            Issued shares - 15 1/2                  $       1         $       1         $       1
         Capital in excess of par value               225,984           225,984            52,519
         Retained (deficit) earnings                   (1,895)           (1,944)          115,636
                                                    ---------         ---------         ---------

TOTAL STOCKHOLDER'S EQUITY                          $ 224,090         $ 224,041         $ 168,156
                                                    ---------         ---------         ---------


TOTAL LIABILITIES AND STOCKHOLDER'S EQUITY          $ 523,855         $ 520,035         $ 443,633
                                                    =========         =========         =========
</TABLE>



                     The accompanying notes are an integral
                      part of these financial statements.
<PAGE>   5
                                                                              4

                   MIDLAND ENTERPRISES INC. AND SUBSIDIARIES
                     CONSOLIDATED STATEMENTS OF CASH FLOWS

<TABLE>
<CAPTION>
                                                                            (000 OMITTED)
                                                                      --------------------------
                                                                      FOR THE THREE MONTHS ENDED
                                                                      MARCH 31,        MARCH 31,
                                                                        2001             2000
                                                                      --------         --------
                                                                                     (Predecessor)
<S>                                                                  <C>              <C>
CASH FLOWS FROM OPERATING ACTIVITIES:
      Net earnings                                                    $     49         $    390
      Adjustments to reconcile net earnings to
           net cash provided by operating activities:
           Amortization of goodwill                                        525               --
           Depreciation and amortization                                 5,828            6,132
           Deferred and current income taxes                                 3              360
           Net loss (gain) on sale of assets                                 7             (123)
           Other changes in assets and liabilities:
                Trade receivables                                       (2,715)          (1,015)
                Materials, supplies & fuel                                 421              701
                Accounts payable                                         1,838           (2,201)
                Accrued expenses and other current liabilities           2,763            2,489
                Other                                                      790              355
                                                                      --------         --------

NET CASH PROVIDED BY OPERATING ACTIVITIES                             $  9,509         $  7,088
                                                                      --------         --------

CASH FLOWS FROM INVESTING ACTIVITIES:
      Capital expenditures                                            $   (399)        $   (502)
      Decrease (increase) in Parent receivable                               9           (6,215)
      Proceeds from asset dispositions                                     717            1,167
                                                                      --------         --------

NET CASH PROVIDED (USED) BY INVESTING ACTIVITIES                      $    327         $ (5,550)
                                                                      --------         --------

CASH FLOWS FROM FINANCING ACTIVITIES:
      Repayment of long-term debt                                     $   (976)        $ (1,246)
      Cash dividends paid to Parent                                         --             (292)
                                                                      --------         --------

NET CASH USED BY FINANCING ACTIVITIES                                 $   (976)        $ (1,538)
                                                                      --------         --------

Net increase in cash and cash equivalents                             $  8,860         $     --
Cash and cash equivalents at beginning of period                        11,179               86
                                                                      --------         --------

Cash and cash equivalents at end of period                            $ 20,039         $     86
                                                                      ========         ========

SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid during the period for:
      Interest, net of amounts capitalized                            $    191         $    308
      Income taxes                                                    $    413         $     42
</TABLE>



                     The accompanying notes are an integral
                      part of these financial statements.
<PAGE>   6

                                                                               5

                    MIDLAND ENTERPRISES INC. AND SUBSIDIARIES
                          NOTES TO FINANCIAL STATEMENTS
                                 MARCH 31, 2001


   (1)  ACCOUNTING POLICIES

   It is Midland Enterprises Inc.'s (the Registrant's) opinion that the
   financial information contained in this report reflects all adjustments
   necessary to present a fair statement of the results for the periods
   reported, but such results are not necessarily indicative of results to be
   expected for the year, due to the somewhat seasonal nature of the
   Registrant's operations. All such adjustments are of a normal, recurring
   nature.

   The preparation of financial statements in conformity with generally accepted
   accounting principles requires management to make estimates and assumptions
   that affect the reported amounts of assets and liabilities, the disclosure of
   contingent assets and liabilities at the date of the financial statements and
   the reported amounts of revenues and expenses during the reporting period.
   Actual results could differ from those estimates.

   Certain information and footnote disclosures normally included in financial
   statements prepared in accordance with generally accepted accounting
   principles have been condensed or omitted in this Form 10-Q pursuant to the
   rules and regulations of the Securities and Exchange Commission. However, the
   disclosures herein when read with the annual report for 2000 filed on Form
   10-K are adequate to make the information presented not misleading.


   (2)  GOODWILL

   In addition to the $60.0 million that was recorded on November 8, 2000 as a
   result of the acquisition of the Registrant's Parent by KeySpan Corporation
   (KeySpan), during the quarter ended March 31, 2001, the Registrant recorded
   additional goodwill of $1.8 million for certain fair value adjustments.
   Goodwill is being amortized over 30 years using the straight-line method.

   The Financial Accounting Standards Board ("FASB") recently issued a revision
   to its Exposure Draft ("ED") on "Business Combinations and Intangible
   Assets". In the ED, the FASB concluded that the amortization of goodwill
   would no longer be required. Instead, companies will need to perform
   impairment tests on the recorded amount and determine whether an impairment
   charge is necessary. The FASB is expected to conclude its deliberations on
   the matter in 2001, and depending on the timing of the final statement, the
   change may have a favorable impact on expected earnings in 2001. Goodwill
   amortization for 2001 is estimated to be approximately $2 million. Such a
   change will not affect cash flow.


   (3)  RESERVE FOR SEPARATION PAYMENTS

   The Registrant recorded a $4.7 million liability for separation payments in
   the fourth quarter of 2000 in conjunction with the acquisition by KeySpan.
   During the first quarter of 2001, payments were made in the amount of $3.1
   million. Including payments made in the fourth quarter of 2000, the remaining
   liability at March 31, 2001 is $.5 million.


<PAGE>   7
                                                                               6


         2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
                            AND RESULTS OF OPERATIONS


RESULTS OF OPERATIONS:
---------------------

First quarter revenues declined 5% from the same period in 2000, primarily
reflecting the absence of the Registrant's Red Circle operations, segments of
which were sold in the second and fourth quarters of last year. Tonnage
transported also declined due to the absence of the Red Circle business as well
as softness in the steel sector. Compared to last year, rates were generally
higher primarily due to fuel adjustment mechanisms contained in multi-year and
annual barge transportation contracts that escalated freight rates in the
quarter, as fuel prices rose 16% as compared to the first quarter of 2000.
Market rates for spot business also improved slightly over the same period last
year, and as a result, overall rates per ton mile increased 12% over the first
quarter of 2000.

First quarter tonnage transported decreased 6% from 2000 while related ton-miles
declined 16% reflecting a shorter average length of haul in addition to the
lower volume. Coal tonnage increased 1%, accounting for 71% of tonnage shipped,
as stronger demand from utilities offset reduced shipments for industrial
customers, specifically steel producers. Utility customers increased shipments
in order to rebuild stockpiles that had been depleted as a result of a shortage
of coal that was experienced in the fourth quarter of 2000, due to problems
experienced with coal suppliers. Demand for metallurgical coal by steel
producers declined as markets for steel products weakened and production was
scaled back. Coal ton-miles decreased 4% however, reflecting a shorter average
length of haul as coal buyers sought to purchase supply from alternative sources
that resulted in a change in shipment patterns. Non-coal tonnage decreased 21%
due in large part to the absence of movements of phosphate rock by Red Circle,
as well as a significant decrease in demand for steel-related raw materials.

While operating conditions in the quarter were generally good, there were
periods of icing and high water that resulted in draft restrictions and reduced
tow sizes, and heavy fog that caused transit delays. Operating costs decreased
5% due to the absence of the Red Circle operations offset mostly by higher fuel
costs. As mentioned previously, while much of the higher fuel costs were
recovered through contractual fuel escalation mechanisms, the Registrant's
subsidiaries were still adversely impacted by the higher costs. As a result of
these factors, and the amortization of goodwill, operating earnings were .9
million below the same period in 2000.

Earnings before income taxes decreased $.3 million from the same period last
year, with lower operating earnings offset somewhat by higher interest income.
Net earnings also declined $.3 million as compared to the first quarter of 2000.

KeySpan Corporation (KeySpan) acquired the Registrant's Parent, Eastern
Enterprises (Eastern), on November 8, 2000. Pursuant to an order of the SEC
issued under PUHCA by which the SEC approved the acquisition of Eastern, KeySpan
is required to divest its interest in the Registrant by November 8, 2003,
because Registrant's operations have been deemed not functionally related to
KeySpan's core utility operations.




<PAGE>   8
                                                                               7

LIQUIDITY AND CAPITAL RESOURCES

Capital expenditures of $.4 million and debt payments of $1.0 million were
funded from cash provided by operating activities. Capital expenditures for 2001
are estimated at $9 million, the majority of which includes major improvements
to towboats and shoreside facilities as well as the purchase of new equipment.
These purchases will be funded with cash provided from operating activities. The
Registrant received 27 barges in the first quarter from the like-kind exchange
agreement on the Red Circle ocean units that were sold in October 2000. In
addition, the Registrant has contracted for delivery of 50 new hopper barges in
the third and fourth quarters of 2001. These barges will be operated under
long-term operating leases.

FORWARD-LOOKING INFORMATION

This report and other Registrant reports and statements issued or made from time
to time contain certain "forward-looking statements" concerning projected future
financial performance or concerning expected plans or future operations. The
Registrant cautions that actual results and developments may differ materially
from such projections or expectations.

Investors should be aware of important factors that could cause actual results
to differ materially from the forward-looking projections or expectations. These
factors include, but are not limited to: the effects of strategic initiatives on
earnings and cash flow, changes in market conditions for barge transportation,
adverse weather and operating conditions on the inland waterways, changes in
economic conditions including interest rates and the value of the dollar versus
other currencies, changes in fuel prices, and regulatory and court decisions.
All of these factors are difficult to predict and are generally beyond the
control of the Registrant.







<PAGE>   9
                                                                               8


                           PART II. OTHER INFORMATION


ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K

   (a)   Reports on Form 8-K

         There were no reports on Form 8-K filed in the first quarter of 2001.






<PAGE>   10
                                                                               9


                                    SIGNATURE


   It is Midland's opinion that the financial information contained in this
   report reflects all normal, recurring adjustments necessary to present a fair
   statement of results for the periods reported; but such results are not
   necessarily indicative of results to be expected for the year, due to the
   seasonal nature of Midland's operations. All accounting policies have been
   applied in a manner consistent with prior periods. Such financial information
   is subject to year-end adjustments and annual audit by independent public
   accountants.

   Pursuant to the requirements of the Securities Exchange Act of 1934, Midland
   has duly caused this report to be signed on its behalf by the undersigned,
   thereunto duly authorized.



                                        MIDLAND ENTERPRISES INC.


                                        BY: /s/ C. LUDWIG
                                           -----------------------------
                                            C.  LUDWIG
                                            CONTROLLER
                                            PRINCIPAL ACCOUNTING OFFICER





   DATE:  MAY 14, 2001