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                                                                     EXHIBIT 4.8

                             DECLARATION OF TRUST
                          OF DYNEGY CAPITAL TRUST III


     This Declaration of Trust, dated as of February 1, 2000 (this "Declaration
of Trust"), among (i) Dynegy Inc., an Illinois corporation, as sponsor (the
"Sponsor"), (ii) Bank One Trust Company, NA, as property trustee (the "Property
Trustee"), (iii) Bank One Delaware, Inc., a Delaware corporation, as trustee
(the "Delaware Trustee"), and (iv) Robert T. Ray, an individual, as trustee (the
"Administrative Trustee") (each of such trustees in (ii), (iii) and (iv) a
"Trustee" and collectively, the "Trustees").  The Sponsor and the Trustees
hereby agree as follows:

          1.   The trust created hereby (the "Trust") shall be known as "Dynegy
Capital Trust III" in which name the Trustees, or the Sponsor to the extent
provided herein, may engage in the transactions contemplated hereby, make and
execute contracts, and sue and be sued.

          2.   The Sponsor hereby assigns, transfers, conveys and sets over to
the Trust the sum of $10.  The Trustees hereby acknowledge receipt of such
amount in trust from the Sponsor, which amount shall constitute the initial
trust estate.  It is the intention of the parties hereto that the Trust created
hereby constitute a business trust under Chapter 38 of Title 12 of the Delaware
Code, 12 Del. C. (S) 3801, et seq. (the "Business Trust Act"), and that this
document constitutes the governing instrument of the Trust.  The Trustees are
hereby authorized and directed to execute and file a certificate of trust with
the Delaware Secretary of State in accordance with the provisions of the
Business Trust Act.

          3.   The Sponsor and the Trustees will enter into an amended and
restated Declaration of Trust, satisfactory to each such party, to provide for
the contemplated operation of the Trust created hereby and the issuance of the
Preferred Securities and Common Securities referred to therein.  Prior to the
execution and delivery of such amended and restated Declaration of Trust, the
Trustees shall not have any duty or obligation hereunder or with respect to the
trust estate, except as otherwise required by applicable law or as may be
necessary to obtain prior to such execution and delivery of any licenses,
consents or approvals required by applicable law or otherwise.

          4.   The Sponsor and the Trustees hereby authorize and direct the
Sponsor, as the sponsor of the Trust, (i) to prepare and file a Registration
Statement (including the Prospectus included therein and any Prospectus
Supplement relating thereto) relating to the Preferred Securities meeting the
requirements of the Securities Act of 1933, as amended (the "1933 Act"), and
such other forms or filings as may be required by the 1933 Act, the Securities
Exchange Act of 1934, as amended, or the Trust Indenture Act of 1939, as
amended, in each case relating to the Preferred Securities of the Trust; (ii) to
file and execute on behalf of the Trust, such applications, reports, surety
bonds, irrevocable consents, appointments of attorney for service of process and
other papers and documents that shall be necessary or desirable to register or
establish the exemption from registration of the Preferred Securities of the
Trust under the securities or "Blue Sky" laws of such jurisdictions as the
Sponsor, on behalf of the Trust, may deem necessary or desirable; (iii) to
execute and file an application, and all other applications, statements,
certificates, agreements and other

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instruments that shall be necessary or desirable, to the New York Stock Exchange
or any other national stock exchange or the Nasdaq National Market for listing
or quotation of the Preferred Securities of the Trust; (iv) to execute and
deliver letters or documents to, or instruments for filing with, a depository
relating to the Preferred Securities of the Trust; and (v) to execute, deliver
and perform on behalf of the Trust one or more underwriting agreements, purchase
agreements, dealer manager agreements, escrow agreements and other related
agreements providing for or relating to the sale of the Preferred Securities of
the Trust.

          5.   This Declaration of Trust may be executed in one or more
counterparts.

          6.   The number of Trustees initially shall be three (3) and
thereafter the number of Trustees shall be such number as shall be fixed from
time to time by a written instrument signed by the Sponsor which may increase or
decrease the number of Trustees; provided, however, that to the extent required
by the Business Trust Act, one Trustee shall either be a natural person who is a
resident of the State of Delaware or, if not a natural person, an entity which
has its principal place of business in the State of Delaware and otherwise meets
the requirements of applicable Delaware law.  Subject to the foregoing, the
Sponsor is entitled to appoint or remove without cause any Trustee at any time.
The Trustees may resign upon thirty (30) days' prior notice to the Sponsor.

          7.   Bank One Delaware, Inc., in its capacity as Trustee, shall not
have the powers or duties of the Trustees set forth herein (except as may be
required under the Business Trust Act) and shall be a trustee hereunder for the
sole and limited purpose of fulfilling the requirements of Section 3807 of the
Business Trust Act.

          8.   This Declaration of Trust shall be governed by, and construed in
accordance with, the laws of the State of Delaware (without regard to conflict
of laws of principles).

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     IN WITNESS WHEREOF, the parties hereto have caused this Declaration of
Trust to be duly executed as of the day and year first above written.

                              DYNEGY INC., as Sponsor


                              By: /s/ Robert T. Ray
                                 ---------------------------------
                              Name:      Robert T. Ray
                              Title:     Vice President


                              BANK ONE TRUST COMPANY, National Association, as
                              Property Trustee


                              By: /s/ John R. Prendiville
                                 ---------------------------------
                              Name:      John R. Prendiville
                              Title:     Vice President


                              BANK ONE DELAWARE, INC.,
                              as Delaware Trustee


                              By: /s/ John R. Prendiville
                                 ---------------------------------
                              Name:      John R. Prendiville
                              Title:     Vice President

                                /s/ Robert T. Ray
                               ---------------------------------------
                              ROBERT T. RAY, as Administrative Trustee

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