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                                                                    EXHIBIT 3.6


                                      DQE

                                    BY-LAWS

                          EFFECTIVE DECEMBER 18, 1996



                                   ARTICLE I



                                  STOCKHOLDERS



          SECTION 1.  Annual Meeting.  The Corporation shall hold an annual
                      ---------------                                      
stockholders' meeting for election of Directors at a date, location (within or
outside Pennsylvania) and time set by the Board of Directors.  Annual meetings
shall be general meetings, open for the transaction of any business within the
powers of the Corporation without special notice of such business, except in
cases in which special notice is required by statute, the Articles or these By-
Laws.

          SECTION 2.  Special Meetings.  Special meetings of the stockholders
                      -----------------                                      
may be called at any time by the Chairman of the Board or President or by the
Board of Directors, and (to the extent permitted by statute) shall be called at
the written request of stockholders owning at least 20% of the shares of capital
stock entitled to be voted at the meeting, which request shall state the purpose
of the proposed meeting.
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          SECTION 3.  Notice of Meetings.  Written notice of every meeting of
                      -------------------                                    
the stockholders shall be given to each stockholder entitled to vote at such
meeting, at least five days (or such other period as required by statute) before
the meeting, by the Chairman of the Board or Secretary.  Failure to give notice
of any annual meeting or irregularity in the notice shall not affect the
validity of any proceedings at such meeting (other than proceedings of which
special notice is required by law, the Articles or these By-Laws).

          SECTION 4.  Quorum.  At all meetings of stockholders, a majority of
                      -------                                                
the outstanding shares of capital stock entitled to vote, represented by
stockholders in person or by proxy, shall constitute a quorum.

          SECTION 5.  Judges of Election.  Three judges of election shall be
                      -------------------                                   
appointed by the Board of Directors for any meeting of stockholders.  The judges
of election shall act as tellers of any ballot vote taken at the meeting and
certify the result.

          SECTION 6.  Voting and Proxies.  Any stockholder having the right to
                      -------------------                                     
vote at any meeting shall be entitled to one vote for each share of stock held.
At meetings for the election of Directors, each stockholder entitled to vote
shall be entitled to votes equal to the number of shares held multiplied by the
number of Directors to be elected, and each stockholder

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may cast all votes for a single candidate or distribute them among any two or
more candidates.

          Any stockholder entitled to vote at any meeting of stockholders may
vote either in person or by proxy, but no proxy which is dated more than three
years prior to the meeting at which it is offered shall confer the right to
vote.  Every proxy shall be in writing, signed by a stockholder or duly
authorized attorney in fact, and dated.

          SECTION 7.  Order of Business.  At all meetings of stockholders, the
                      ------------------                                      
order of business shall be, as far as applicable and practicable, as follows:

          (1) Organization.

          (2) Proof of giving of the notice of meeting or of
              waivers thereof.

          (3) Submission by the Secretary, or by the judges of
              election, of a list of stockholders entitled to vote, present
              in person or by proxy.

          (4) If an annual meeting, presentation of unapproved
              minutes of preceding meetings and action thereon.

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          (5) Matters to be voted upon as specified in the
              notice of meeting.

          (6) Reports.

          (7) Unfinished business.

          (8) New business.

          (9) Adjournment.



                                   ARTICLE II

                               BOARD OF DIRECTORS


          SECTION 1.  Election and Powers.  The business and affairs of the
                      --------------------                                 
Corporation shall be managed by its Board of Directors.  The Board may exercise
all the powers of the Corporation except such as are by statute, the Articles or
these By-Laws conferred upon or reserved to the stockholders.  At each annual
meeting the stockholders shall elect directors of the class whose term then
expires, to hold office until the third succeeding annual meeting.  Except as
otherwise expressly

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provided in the Articles, each director shall hold office until a successor is
elected and qualified, or until such director's earlier death, resignation or
removal in the manner provided in Section 11 of this Article II. The number of
directors which shall constitute the full Board of Directors shall be not less
than one as fixed by the Board of Directors.

          SECTION 2.  Lead Directors.  Directors who are not employees of the
                      --------------                                         
Company (the "outside directors") may elect one or two outside directors on an
annual basis to serve as Lead Director(s) of the Board.  In the absence of the
Chairman and President, or at the request of the Board of Directors, a Lead
Director may chair meetings of the stockholders or Board of Directors.  A Lead
Director may also 1) call for and chair meetings of the outside directors and 2)
consult with and advise the Chairman, President and Chief Executive Officer of
the Company on matters of Board and corporate governance.

          SECTION 3.  Eligibility for Election.  No person who is an employee of
                      ------------------------                                  
the Company, except the Chairman of the Board or President, shall be eligible to
serve as a Director of the Company after retiring as an employee.  The mandatory
retirement age for directors is 70 except for directors completing a

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current term of office or directors currently serving as Lead Directors.

          SECTION 4.  Regular Meetings.  After each meeting of stockholders at
                      -----------------                                       
which Directors shall have been elected, the Board of Directors shall meet as
soon as practicable for the purpose of organization and the transaction of other
business.  Additional regular meetings shall be held as fixed by the Board of
Directors.

          SECTION 5.  Special Meetings.  Special meetings of the Board of
                      -----------------                                  
Directors shall be held whenever called by the Chairman of the Board, the
President or a majority of the Board of Directors.

          SECTION 6.  Place of Meetings.  The Board of Directors may hold its
                      ------------------                                     
regular and special meetings at such places as it designates.

          SECTION 7.  Notice of Meetings.  No notice of regular meetings of the
                      -------------------                                      
Board of Directors need be given.  Notice of the place, day and hour of every
special meeting shall be given to each director at least one day before the
meeting, by personal, telex or telephonic notification, at the director's
residence or usual place of business, or in the alternative, upon three days'

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notice to the director's last known mailing address.  The failure to give notice
shall not affect the validity of any meeting as to any director who attends the
meeting or waives notice in writing.  No notice of adjourned meetings of the
Board of Directors need be given.  All regular and special meetings of the Board
of Directors shall be general meetings open for the transaction of any business
without special notice of such business.

          SECTION 8.  Quorum.  At all meetings of the Board of Directors, a
                      -------                                              
majority of the directors shall constitute a quorum for the transaction of
business.  Except in cases in which it is by law, the Articles or these By-Laws
otherwise provided, a majority of the quorum shall decide any questions.

          SECTION 9.  Vacancies.  Vacancies on the Board of Directors shall be
                      ----------                                              
filled as provided in the Articles.

          SECTION 10.  Compensation.  The directors may be compensated for their
                       -------------                                            
services on a periodic basis and/or receive a fixed sum for attendance at each
regular, special or Committee meeting and every adjournment thereof.  The amount
shall be fixed by resolution of the Board of Directors.  The directors shall be
reimbursed for all reasonable traveling expenses incurred in attending meetings.
Directors who are

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employees of the Corporation shall not be paid for their services as directors.

          SECTION 11.  Removal.  Any Director, any class of Directors or the
                       --------                                             
entire Board of Directors may be removed as provided in the Articles.

          SECTION 12.  Indemnification of Directors and Officers.
                       ------------------------------------------


          (a) Right of Indemnification.  Except as prohibited by law, every
              -------------------------                                    
Director and officer of the Corporation shall be entitled as of right to be
indemnified by the Corporation against reasonable expense and any liability paid
or incurred by such person in connection with any actual or threatened claim,
action, suit or proceeding, civil, criminal, administrative, investigative or
other, whether brought by or in the right of the Corporation or otherwise, by
reason of such person being or having been a Director or officer of the
Corporation or by reason of the fact that such person is or was serving at the
request of the Corporation as a director, officer, employee, fiduciary or other
representative of another corporation, partnership, joint venture, trust,
employee benefit plan or other entity (such claim, action, suit or proceeding
hereinafter being referred to as "action"); provided, however, that no such

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right of indemnification shall exist with respect to an action brought by a
Director or officer against the Corporation (other than a suit for
indemnification as provided in paragraph (b)).  Such indemnification shall
include the right to have expenses incurred by such person in connection with an
action paid in advance by the Corporation prior to final disposition of such
action, subject to such conditions as may be prescribed by law.  Persons who are
not Directors or officers of the Corporation may be similarly indemnified in
respect of service to the Corporation or to another such entity at the request
of the Corporation to the extent the Board of Directors at any time denominates
such person as entitled to the benefits of this Section.  As used herein,
"expense" shall include fees and expenses of counsel selected by such person;
and "liability" shall include amounts of judgments, excise taxes, fines and
penalties, and amounts paid in settlement.

          (b) Right of Claimant to Bring Suit.  If a claim under paragraph (a)
              --------------------------------                                
of this Section is not paid in full by the Corporation within thirty days after
a written claim has been received by the Corporation, the claimant may at any
time thereafter bring suit against the Corporation to recover the unpaid amount
of the claim, and, if successful in whole or in part, the claimant shall also be
entitled to be paid the expense of prosecuting such claim.  It shall be a
defense to any such action that the conduct of the claimant was such that under
Pennsylvania law the Corporation would be prohibited from

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indemnifying the claimant for the amount claimed, but the burden of proving such
defense shall be on the Corporation.  Neither the failure of the Corporation
(including its Board of Directors, independent legal counsel and its
stockholders) to have made a determination prior to the commencement of such
action that indemnification of the claimant is proper in the circumstances
because the conduct of the claimant was not such that indemnification would be
prohibited by law, nor an actual determination by the Corporation (including its
Board of Directors, independent legal counsel or its stockholders) that the
conduct of the claimant was such that indemnification would be prohibited by
law, shall be a defense to the action or create a presumption that the conduct
of the claimant was such that indemnification would be prohibited by law.


  (c) Insurance and Funding.  The Corporation may purchase and maintain
      ----------------------                                           
insurance to protect itself and any person eligible to be indemnified hereunder
against any liability or expense asserted or incurred by such person in
connection with any action, whether or not the Corporation would have the power
to indemnify such person against such liability or expense by law or under the
provisions of this Section 12.  The Corporation may create a trust fund, grant a
security interest, cause a letter of credit to be issued or use other means
(whether or not similar to the foregoing) to ensure the payment of such sums as
may become necessary to effect indemnification as provided herein.

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          (d) Non-Exclusivity; Nature and Extent of Rights.  The right of
              ---------------------------------------------              
indemnification provided for herein (1) shall not be exclusive of any other
rights, whether existing now or later, to which those seeking indemnification
may be entitled under any agreement, by-law or charter provision, vote of
stockholders or Directors or otherwise, (2) shall be deemed to create
contractual rights in favor of persons entitled to indemnification, (3) shall
continue as to persons who have ceased to have the status pursuant to which they
were entitled or were denominated as entitled to indemnification and shall inure
to the benefit of the heirs and legal representatives of persons entitled to
indemnification hereunder and (4) shall be applicable to actions, suits or
proceedings commenced after adoption, whether arising from acts or omissions
occurring before or after the adoption hereof. The right of indemnification may
not be amended, modified or repealed so as to limit the indemnification provided
herein with respect to any acts or omissions occurring prior to the adoption of
any such amendment or repeal.

                 SECTION 13.  Personal Liability of Directors.
                              --------------------------------

          (a) To the fullest extent that the laws of the Commonwealth of
Pennsylvania, as in effect on January 27, 1987 or as thereafter amended, permit
elimination or limitation of

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the liability of directors, no Director of the Corporation shall be personally
liable for monetary damages as such for any action taken, or any failure to take
any action, as a Director.

          (b) This Section 13 shall not apply to any action filed prior to
January 27, 1987, nor to any breach of performance or failure of performance of
duty by a Director occurring prior to January 27, 1987.  Any amendment or repeal
of this Section 13 which has the effect of increasing Director liability shall
operate prospectively only, and shall not affect action taken, or any failure to
act, prior to its adoption.

          SECTION 14.  Applicable Law.  Pennsylvania Business Corporation Law of
                       ---------------                                          
1988, as amended, Title 15, Part II, Subpart B, Article C, Chapter 25,
Subchapters G through J, shall not apply to the Corporation.

                                  ARTICLE III

                                   COMMITTEES


          Committees.  The Board of Directors may by resolution designate and
          -----------                                                        
discontinue such standing or special committees as it deems desirable.  Each
committee shall have such powers and perform such duties, not inconsistent with
law, as may be assigned by the Board of Directors.

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                                   ARTICLE IV

                                    OFFICERS


          SECTION 1.  Executive Officers.  The executive officers of the
                      -------------------                               
Corporation shall be a Chairman of the Board, a President, one or more Vice
Presidents, a Secretary, a Treasurer and a Controller.  The Chairman of the
Board and the President shall be chosen from among the Directors.  The executive
officers shall be elected annually by the Board of Directors at its first
meeting following the annual meeting, and each such officer shall hold office
until the corresponding meeting in the next year and until a successor has been
duly chosen and qualified, or until such officer's earlier death, resignation or
removal.  Any vacancy in the above offices may be filled for the unexpired
portion of the term by the Board of Directors, at any regular or special
meeting.

          SECTION 2.  Chairman of the Board.  The Chairman of the Board shall
                      ----------------------                                 
preside at any meeting of the stockholders or of the Board of Directors and
shall have all the powers and authority vested in a presiding officer by law or
practice to conduct an orderly meeting.  In addition to any specific powers

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conferred by these By-Laws, the Chairman of the Board shall have the powers and
duties assigned by the Board of Directors.

          SECTION 3.  President.  In addition to any specific powers conferred
                      ----------                                              
by these By-Laws, the President shall have the powers and duties assigned by the
Board of Directors.  At the request or in the absence or disability of the
Chairman of the Board, the President shall preside at any meeting of the
stockholders or of the Board of Directors.

          SECTION 4.  Chief Executive Officer.  The Board of Directors shall
                      ------------------------                              
designate the Chairman of the Board or President or the person holding both of
such offices to perform the functions of the Chief Executive Officer.  The Chief
Executive  Officer shall carry out the policies approved by the Board of
Directors.  In addition to any specific powers conferred by these By-Laws, the
Chief Executive Officer shall have supervision over, and shall exercise general
executive powers concerning, all the operations and business of the Corporation.
The Chief Executive Officer shall also have and exercise such powers and duties
as assigned by the Board of Directors and may delegate executive and other
powers and duties to any other officer.

          SECTION 5.  Vice Presidents.  At the request of the President, or in
                      ----------------                                        
the absence or disability of the President, any Vice President shall perform the
duties of the President, and when so acting shall have the powers of the
President, unless

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otherwise determined by the Board of Directors.  Each Vice President shall also
have and exercise such powers and duties as assigned by the Board of Directors
or the Chief Executive Officer.

          SECTION 6.  Secretary.  The Secretary shall perform all duties
                      ----------                                        
incident to the office of a secretary of a corporation, and such other duties as
assigned by the Board of Directors or the Chief Executive Officer.

          SECTION 7.  Treasurer.  The Treasurer shall perform all the duties
                      ----------                                            
incident to the office of a treasurer of a corporation, and such other duties as
assigned by the Board of Directors or the Chief Executive Officer.

          SECTION 8.  Controller.  The Controller shall perform all duties
                      -----------                                         
incident to the office of a controller of a corporation, and such other duties
as assigned by the Board of Directors or the Chief Executive Officer.

          SECTION 9.  Assistant Officers.  The Board of Directors may elect one
                      -------------------                                      
or more Assistant Vice Presidents, Assistant Secretaries and Assistant
Treasurers.  Each assistant officer shall hold office for such period and shall
have such authority and perform such duties as the Board of Directors or the
Chief Executive Officer may prescribe.

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          SECTION 10.  Certain Powers of Officers.  Except in cases in which the
                       --------------------------                               
signing and execution shall have been expressly delegated by the Board of
Directors to some other officer, employee or agent of the Corporation, the
Chairman of the Board or President or a Vice President may sign and execute in
the name of the Corporation all authorized deeds, mortgages, bonds, contracts or
other instruments; provided, however, that a Vice President may delegate to any
General Manager or Manager reporting to such officer authority to sign and
execute in the name of the Corporation all authorized contracts and similar
instruments pursuant to a policy approved by the Board of Directors.

          SECTION 11.  Compensation.  The Board of Directors shall have the
                       -------------                                       
power to fix the compensation of the Chairman of the Board, President and any
Vice President of the Corporation.  The Chief Executive Officer shall have the
power to fix the compensation of the Secretary, the Treasurer, the Controller
and assistant officers.

                                   ARTICLE V

                                     STOCK

          SECTION 1.  Certificates.  Every stockholder shall be entitled to a
                      -------------                                          
certificate or certificates of stock of the

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Corporation in a form prescribed by the Board of Directors, duly numbered and
sealed with the corporate seal of the Corporation, and setting forth the number
and kind of shares represented thereby; provided however, that the Board of
Directors shall have the power to provide for uncertificated shares of any class
or series of stock or any part thereof.  The certificates shall be signed, by
facsimile or otherwise, by the Chairman of the Board, the President or a Vice
President and by the Treasurer or the Secretary and shall bear the corporate
seal, which may be a facsimile, engraved or printed. The Board of Directors may
also appoint one or more Transfer Agents and/or Registrars for its stock of any
class and may require stock certificates to be countersigned, by facsimile or
otherwise, and/or registered by one or more of such Transfer Agents and/or
Registrars. In case any officer, Transfer Agent or Registrar who has signed or
whose facsimile signature or authentication has been placed upon any share
certificate shall have ceased to be such officer, Transfer Agent or Registrar
because of death, resignation or otherwise, before the certificate is issued,
the certificate may be issued with the same effect as if the officer, Transfer
Agent or Registrar had not ceased to be such at the date of its issue.

          SECTION 2.  Transfer of Shares.  The Board of Directors shall have
                      -------------------                                   
power and authority to make all rules and regulations concerning the issue,
transfer, and registration of certificates of stock.

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          SECTION 3.  Record Dates.  The Board of Directors shall have the
                      -------------                                       
authority to fix in advance a date, not exceeding ninety (90) days preceding any
meeting of stockholders, or the date for payment of any dividend, or the date
for the allotment of rights, or the date when any change, conversion, or
exchange of capital stock shall go into effect (each a "stockholder event"), as
a record date, in connection with such stockholder event, and in such case only
such stockholders as shall be stockholders of record on the date so fixed shall
be entitled to participate in such stockholder event, notwithstanding any
transfer of any stock on the books of the Corporation after any such record
date.

          SECTION 4.  Mutilated, Lost or Destroyed Certificates.
                      ----------------------------------------- 

The holder of any certificate representing shares of stock of the Corporation
shall immediately notify the Corporation of any mutilation, loss or destruction
thereof, and the Board of Directors may, in its discretion, cause one or more
new certificates, for the same number of shares in the aggregate, to be issued
to such holder upon the surrender of the mutilated certificate, or in case of
loss or destruction of the certificate, upon satisfactory proof of such loss or
destruction and the deposit of indemnity by way of bond or otherwise, in such
form and amount and with such sureties or security as the Board of Directors may
require to indemnify the Corporation against loss or liability by reason of the
issuance of such new

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certificate or certificates, and the failure of such holder to comply with such
requirements shall constitute a waiver by such holder of any right to receive
such new certificate or certificates.


                                   ARTICLE VI

                             DIVIDENDS AND FINANCE


          SECTION 1.  Dividends.  Subject to the provisions of the Articles, the
                      ----------                                                
Board of Directors may, in its discretion, declare what, if any, dividends shall
be paid upon the stock of the Corporation.  Except as otherwise provided by the
Articles, dividends shall be payable upon such dates as the Board of Directors
may designate.  Before payment of any dividend there may be set aside out of any
funds of the Corporation available for dividends such sum or sums as the
Directors, in their absolute discretion, think proper as a reserve fund to meet
contingencies, for equalizing dividends, or for repairing or maintaining any
property of the Corporation, or for such other purposes as the Directors shall
think conducive to the interests of the Corporation, and the Directors may
abolish any such reserve in the manner in which it is created.

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          SECTION 2.  Checks, Drafts, Etc.  Unless otherwise provided by
                      --------------------                              
resolution of the Board of Directors, all checks, drafts, or orders for the
payment of money, notes, and other evidences of indebtedness, issued in the name
of the Corporation, shall be signed by the Treasurer or an Assistant Treasurer
and countersigned by the Chairman of the Board, the President or a Vice
President.

          SECTION 3.  Fiscal Year.  The fiscal year of the Corporation shall be
                      ------------                                             
the calendar year, unless otherwise provided by the Board of Directors.


                                  ARTICLE VII

                               SUNDRY PROVISIONS


          SECTION 1.  Seal.  The Corporate Seal of the Corporation shall contain
                      -----                                                     
within a circle the words "DQE", and in an inner circle the word "SEAL".

          SECTION 2.  Inspection of Books and Records.  The Board of Directors
                      --------------------------------                        
may determine whether and, if allowed, when and under what conditions and
regulations, the books and records of the Corporation shall be open to the
inspection of stock-

                                       20
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holders, and the rights of stockholders in this respect are and shall be limited
accordingly, except as otherwise provided by statute.  No stockholder has the
right to inspect any book or record or receive any statement for an improper
purpose.

          SECTION 3.  Bonds.  The Board of Directors may require any officers,
                      ------                                                  
agents, or employees of the Corporation to give a bond to the Corporation,
conditioned upon the faithful discharge of their duties, with one or more
sureties and in such amount as may be satisfactory to the Board of Directors.

          SECTION 4.  Voting Upon Stock in Other Corporations.  Any stock in
                      ----------------------------------------              
other corporations, which may be held by the Corporation, may be represented and
voted at any meeting of stockholders of such other corporations by the Chairman
of the Board, the President or a Vice President of the Corporation or by proxy
executed in the name of the Corporation by the Chairman of the Board, the
President or a Vice President with the corporate seal affixed and attested by
the Secretary or an Assistant Secretary.

          SECTION 5.  Amendments.  Except as provided by the Articles or by
                      -----------                                          
statute, the authority to adopt, amend and repeal the By-Laws is exclusively
vested in the Board of Directors.

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<PAGE>
 
          SECTION 6.  Participation in Meeting by Telephone.  One or more
                      --------------------------------------             
Directors may participate in a meeting of the Board of Directors or a committee
of the Board of Directors by means of a conference telephone or similar
communications equipment by means of which all persons participating in the
meeting can communicate with each other.

          SECTION 7.  Informal Action by Directors or Committees.
                      -------------------------------------------

Any action which may be taken at a meeting of the Board of Directors or a
committee of the Board of Directors may be taken without a meeting if a consent
or consents in writing setting forth the action so taken shall be signed by all
of the Directors or the members of the committee and shall be filed with the
Secretary of the Corporation.

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