EXHIBIT 4.31

FOURTH AMENDMENT AND SUPPLEMENT
TO CREDIT AGREEMENT
(Multi-Year Revolving Credit Facility)

THIS
FOURTH AMENDMENT AND SUPPLEMENT TO CREDIT AGREEMENT (this Fourth
Amendment) is made and entered into as of the 30th day of October,
2003, effective as of September 30, 2003 (the Fourth Amendment Effective
Date), among ENTERPRISE PRODUCTS OPERATING L.P., a Delaware limited partnership
(Borrower); WACHOVIA BANK, NATIONAL ASSOCIATION (formerly known as
First Union National Bank), as administrative agent (in such capacity, the
Administrative Agent) for each of the lenders (the
Lenders) that is a signatory or which becomes a signatory to the
hereinafter defined Credit Agreement; and the Lenders party hereto.

R E C I T A L S:

A.    
          On November 17, 2000, the Borrower, the Lenders and the Administrative Agent
          entered into a certain Credit Agreement (as amended by First Amendment to Credit
          Agreement dated April 19, 2001, and as further amended and supplemented by
          Second Amendment and Supplement to Credit Agreement dated as of April 24,
          2002, and as further amended and supplemented by Third Amendment and Supplement
          to Credit Agreement dated as of July 31, 2002, the Credit
          Agreement) whereby, upon the terms and conditions therein stated, the
          Lenders agreed to make certain Loans (as defined in the Credit Agreement) and
          extend certain credit to the Borrower.

B.    
          The parties hereto mutually desire to further amend the Credit Agreement as
          hereinafter set forth.

NOW,
THEREFORE, in consideration of the mutual covenants and agreements herein contained, the
Borrower, the Lenders party hereto and the Administrative Agent hereby agree as follows:

1.    Certain Definitions.

| | 1.1 | Terms
Defined Above. As used in this Fourth Amendment, the terms Administrative Agent,
Borrower, Credit Agreement, Fourth Amendment and
Fourth Amendment Effective Date, shall have the meanings indicated above.
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| | 1.2 | Terms
Defined in Agreement. Unless otherwise defined herein, all terms beginning with a
capital letter which are defined in the Credit Agreement shall have the same meanings
herein as therein unless the context hereof otherwise requires.
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2.    
          Amendments to Credit Agreement.

| | 2.1 | Defined
Terms.
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| | (a) | The
term Agreement, as defined in Section 1.02 of the Credit
          Agreement, is hereby amended to mean the Credit Agreement, as amended and
          supplemented by this Fourth Amendment and as the same may from time to time be
          further amended or supplemented.
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| | (b) | The
term Consolidated EBITDA is hereby amended in its entirety to read
as follows:
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| | Consolidated
EBITDA means for any period, the sum of (a) the consolidated net income of the
Borrower and its consolidated Subsidiaries (excluding Project Finance Subsidiaries) for
such period plus, to the extent deducted in determining consolidated net income for such
period, the aggregate amount of (i) Consolidated Interest Expense, (ii) income tax expense
and (iii) depreciation and amortization expense plus (b) the amount of cash dividends
actually received during such period by the Borrower or a Subsidiary (other than a Project
Finance Subsidiary) from a Project Finance Subsidiary plus (c) the amount of all payments
during such period on leases of the type referred to in clause (d) of the definition
herein of Indebtedness and the amount of all payments during such period under other
off-balance sheet loans and financings of the type referred to in such clause (d).
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| | (c) | The
term Material Adverse Change is hereby amended in its entirety to
read as follows
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| | Material
Adverse Change means a material adverse change, from that in effect on December 31,
2002, in the financial condition or results of operations of the Borrower and its
consolidated Subsidiaries taken as a whole, as indicated in the most recent quarterly or
annual financial statements, except as otherwise disclosed in the Borrowers and/or
the Limited Partners filings with the SEC prior to the Fourth Amendment Effective
Date.
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| | (d) | The
term Program is hereby amended in its entirety to read as follows:
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| | Program
means the buy-back program initiated by the Limited Partner whereby the Limited Partner or
the Borrower may after November 17, 2000 buy back up to the greater of (i) 2,000,000
publicly held Common Units or (ii) the number of publicly held Common Units the aggregate
purchase price of which is $30,000,000.
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| | (e) | The
term 364-Day Credit Facility is hereby amended in its entirety to
read as follows:
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| | 364-Day
Credit Facility means the revolving credit facility of the Borrower under that
certain 364-Day Revolving Credit Agreement dated as of October 30, 2003, among the
Borrower, Wachovia Bank, National Association, as Administrative Agent, and the lenders
party thereto, together with any and all amendments and supplements thereto (the
364-Day Credit Agreement).
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| | (f) | The
terms Subordinated Units and Units are hereby deleted
in their entirety.
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| | 2.2 | Additional
Defined Term. Section 1.02 of the Credit Agreement is hereby further amended and
supplemented by adding the following new definitions, which read in their entirety as
follows:
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| | Fourth
Amendment means that certain Fourth Amendment and Supplement to Credit Agreement
dated effective as of October 30, 2003, among the Borrower, the Lenders party thereto and
the Administrative Agent.
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| | Fourth
Amendment Effective Date means October 30, 2003".
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| | 2.3 | Not
a Reportable Transaction. Article III of the Credit Agreement is hereby amended and
supplemented by adding the following new Section 3.14, which reads in its entirety as
follows:
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| | SECTION
3.14 Not a Reportable Transaction. The Borrower does not intend to
treat the Borrowings and related transactions as being a reportable
transaction (within the meaning of Treasury Regulation Section 1.6011-4). In
the event the Borrower determines to take any action inconsistent with such intention, it
will promptly notify the Administrative Agent thereof. If the Borrower so notifies the
Administrative Agent, the Borrower acknowledges that one or more of the Lenders may treat
its Loans as part of a transaction that is subject to Treasury Regulation Section
301.6112-1, and such Lender or Lenders will maintain the lists and other records required
by such Treasury Regulation.
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| | 2.4 | Indebtedness.
 Section  6.01(a) of the Credit  Agreement  is hereby  amended  in its  entirety  to read
as follows:
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| | (a)   
               Indebtedness of any Person that becomes a Subsidiary of the Borrower, to the
               extent such Indebtedness is outstanding at the time such Person becomes a
               Subsidiary of the Borrower and was not incurred in contemplation thereof and
               Indebtedness refinancing (but not increasing) such Indebtedness, and
               Indebtedness assumed by any Subsidiary in connection with its acquisition
               (whether by merger, consolidation, acquisition of all or substantially all of
               the assets or acquisition that results in the ownership of greater than fifty
               percent (50%) of the Equity Interests of a Person) of another Person and
               Indebtedness refinancing (but not increasing) such Indebtedness, provided
               that at the time of and after giving effect to the incurrence or
               assumption of such Indebtedness or refinancing Indebtedness and the application
               of the proceeds thereof, as the case may be, the aggregate principal amount of
               all such Indebtedness, and of all Indebtedness previously incurred or assumed
               pursuant to this Section 6.01(a), and then outstanding, shall not exceed 75% of
               Consolidated EBITDA for the period of four full fiscal quarters of the Borrower
               and its Subsidiaries (and such Person on a pro forma basis) then most recently
               ended; further provided, however, Indebtedness assumed in
               connection with the acquisition of equity interests in Seminole Pipeline
               Company, a Delaware corporation, shall be included as Indebtedness assumed
               pursuant to this Section 6.01(a);"
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| | 2.5 | Ratio
of  Consolidated  Indebtedness to Consolidated  EBITDA.  Section 6.07(b) of the Credit
 Agreement is hereby amended in its entirety to read as follows:
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| | (b)   
               Ratio of Consolidated Indebtedness to Consolidated EBITDA. The Borrower
               shall not permit its ratio of Consolidated Indebtedness to Consolidated EBITDA
               in each case for the four full fiscal quarters most recently ended (including,
               without limitation, the four fiscal-quarter period ending September 30, 2003) to
               exceed 4.75 to 1.00 as of the last day of any fiscal quarter of Borrower. For
               purposes of calculating such ratio the Project Finance Subsidiaries shall be
               disregarded. For purposes of this Section 6.07(b), if during any period of four
               fiscal quarters the Borrower or any Subsidiary acquires any Person (or any
               interest in any Person) or all or substantially all of the assets of any Person,
               the EBITDA attributable to such assets or an amount equal to the percentage of
               ownership of the Borrower or a Subsidiary, as the case may be, in such Person
               times the EBITDA of such Person, for such period determined on a pro forma basis
               (which determination, in each case, shall be subject to approval of the
               Administrative Agent, not to be unreasonably withheld) may be included as
               Consolidated EBITDA for such period as if such acquisition occurred on the first
               day of such four fiscal quarter period; provided that during the
               portion of such period that follows such acquisition, the computation in respect
               of the EBITDA of such Person or such assets, as the case may be, shall be made
               on the basis of actual (rather than pro forma) results.
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| | 2.6 | Notices.
 Section 9.01(a) of the Credit Agreement is hereby amended in its entirety to read as
follows:
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| | (a)   
               if to the Borrower, to it at 2727 North Loop West, 7th Floor,
               Houston, Texas 77008 (for delivery), Attention of Treasurer; P. O. Box 4324,
               Houston Texas 77210 (for mail) (Telecopy No. 713/803-8200);"
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| | 2.7 | Pro
Rata Assignments.  Section 9.04(h) of the Credit Agreement is hereby deleted in its
entirety.
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| | 2.8 | Confidentiality.
 Section  9.12  of the  Credit  Agreement  is  hereby  amended  and  supplemented  in its
entirety to read as follows:
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| | SECTION
9.12. Confidentiality. Each of the Administrative Agent, the Syndication Agent, the
Co-Documentation Agents, and the Lenders agrees to maintain the confidentiality of the
Information (as defined below), except that Information may be disclosed (a) to its and
its Affiliates directors, officers, employees and agents, including accountants,
legal counsel and other advisors (it being understood that the Persons to whom such
disclosure is made will be informed of the confidential nature of such Information and
instructed to keep such Information confidential), (b) to the extent requested by any
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| | regulatory authority, (c) to the extent required by applicable laws or regulations or by
any subpoena or similar legal process, (d) to any other party to this Agreement, (e) in
connection with the exercise of any remedies hereunder or any suit, action or proceeding
relating to this Agreement or the enforcement of rights hereunder, (f) subject to an
agreement containing provisions substantially the same as those of this Section, to any
assignee of or Participant in, or any prospective assignee of or Participant in, any of
its rights or obligations under this Agreement, (g) with the consent of the Borrower or
(h) to the extent such Information (i) becomes publicly available other than as a result
of a breach of this Section or (ii) becomes available to the Administrative Agent,
Syndication Agent, the Co-Documentation Agents or any Lender on a nonconfidential basis
from a source other than the Borrower and its Related Parties. Notwithstanding anything
herein to the contrary, Information shall not include, and the Administrative Agent and
each Lender may disclose without limitation of any kind, any Information with respect to
the tax treatment and tax structure (in each case, within the
meaning of Treasury Regulation Section 1.6011-4) of the transactions contemplated
hereby and all materials of any kind (including opinions or other tax analyses) that are
provided to the Administrative Agent or such Lender relating to such tax treatment and tax
structure; provided that with respect to any document or similar item that in
either case contains Information concerning the tax treatment or tax structure of the
transaction as well as other Information, this sentence shall only apply to such portions
of the document or similar item that relate to the tax treatment or tax structure of the
Loans and transactions contemplated hereby. For the purposes of this Section,
Information means all information received from the Borrower relating
to the Borrower or its business, other than any such information that is available to the
Administrative Agent or any Lender on a nonconfidential basis prior to disclosure by the
Borrower.
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| | 2.9 | Conditions
Precedent. In addition to all other applicable conditions precedent contained in the
Credit Agreement, the obligation of the Lenders party hereto and the Administrative Agent
to enter into this Fourth Amendment shall be conditioned upon the following conditions
precedent:
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| | (a) | The
Administrative Agent shall have received a copy of this Fourth Amendment, duly
completed and executed by the Borrower and the Required Lenders; and
          acknowledged and ratified by the Limited Partner;
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| | (b) | The
Administrative Agent shall have received such other information, documents or
instruments as it or its counsel may reasonably request.
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3.    
          Representations and Warranties. The Borrower represents and warrants
          that:

| | (a) | there
exists no Default or Event of Default, or any condition or act which
          constitutes, or with notice or lapse of time or both would constitute, an Event
          of Default under the Credit Agreement, as hereby amended and supplemented;
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| | (b) | the
Borrower has performed and complied with all covenants, agreements and
          conditions contained in the Credit Agreement, as hereby amended and
          supplemented, required to be performed or complied with by it; and
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| | (c) | the
representations and warranties of the Borrower contained in the Credit
Agreement, as hereby amended and supplemented, were true and correct when made,
and are true and correct in all material respects at and as of the time of
delivery of this Fourth Amendment, except to the extent such representations
and warranties relate to an earlier date, in which case such representations
and warranties were true and correct in all material respects as of such
earlier date.
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4.    
          Extent of Amendments. Except as expressly herein set forth, all of the
          terms, conditions, defined terms, covenants, representations, warranties and all
          other provisions of the Credit Agreement are herein ratified and confirmed and
          shall remain in full force and effect.

5.    
          Counterparts. This Fourth Amendment may be executed in two or more
          counterparts, and it shall not be necessary that the signatures of all parties
          hereto be contained on any one counterpart hereof; each counterpart shall be
          deemed an original, but all of which together shall constitute one and same
          instrument.

6.    
          References. On and after the Fourth Amendment Effective Date, the terms
          Agreement, hereof, herein,
          hereunder, and terms of like import when used in the Credit
          Agreement shall, except where the context otherwise requires, refer to the
          Credit Agreement, as amended and supplemented by this Fourth Amendment.

7.    
          Governing Law. This Fourth Amendment shall be governed by and construed
          in accordance with the laws of the State of New York and applicable federal law.

THIS
FOURTH AMENDMENT, THE CREDIT AGREEMENT, AS AMENDED HEREBY, THE NOTES AND THE OTHER LOAN
DOCUMENTS REPRESENT THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY
EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES.

THERE
ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

This
Fourth Amendment shall benefit and bind the parties hereto, as well as their respective
assigns, successors, heirs and legal representatives.

[Signatures Begin on
Next Page]

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EXECUTED
as of the Fourth Amendment Effective Date.

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|ENTERPRISE PRODUCTS OPERATING L.P.
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|WACHOVIA BANK, NATIONAL ASSOCIATION
(formerly known as First Union National Bank),
Individually and as Administrative Agent
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ACKNOWLEDGMENT AND
RATIFICATION OF GUARANTOR

The
undersigned (Guarantor) hereby expressly (i) acknowledges the
terms of the foregoing Fourth Amendment and Supplement to Credit Agreement;
(ii) ratifies and affirms its obligations under its Guaranty Agreement dated as of
November 17, 2000, in favor of the Administrative Agent; (iii) acknowledges, renews
and extends its continued liability under said Guaranty Agreement and Guarantor hereby
agrees that its Guaranty Agreement remains in full force and effect; and (iv) guarantees
to the Administrative Agent the prompt payment when due of all amounts owing or to be
owing by it under its Guaranty Agreement pursuant to the terms and conditions thereof, as
modified hereby.

The
foregoing acknowledgment and ratification of the undersigned Guarantor shall be evidenced
by signing the spaces provided below, to be effective as of the Fourth Amendment Effective
Date.

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