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                                                                    EXHIBIT 10.1

                     AMENDMENT NO. 1 TO AMENDED AND RESTATED
                       AGREEMENT OF LIMITED PARTNERSHIP OF
                          WILLIAMS ENERGY PARTNERS L.P.

         THIS AMENDMENT NO. 1 TO AMENDED AND RESTATED AGREEMENT OF LIMITED
PARTNERSHIP OF WILLIAMS ENERGY PARTNERS L.P. (this "Amendment"), dated as of
April 11, 2002, is entered into and effectuated by Williams GP LLC, a Delaware
limited liability company, as the General Partner, pursuant to authority granted
to it in Section 5.6 of the Amended and Restated Agreement of Limited
Partnership of Williams Energy Partners L.P., dated as of February 9, 2001, as
amended (the "Partnership Agreement"). Capitalized terms used but not defined
herein are used as defined in the Partnership Agreement.

         WHEREAS, Section 5.6 of the Partnership Agreement provides that the
General Partner, without the approval of any Limited Partners, may issue
additional Partnership Securities, or classes or series thereof, for any
Partnership purpose at any time and from time to time, and may issue such
Partnership Securities for such consideration and on such terms and conditions
as shall be established by the General Partner in its sole discretion; and

         WHEREAS, Section 13.1 of the Partnership Agreement provides that the
General Partner, without the approval of any Partner (subject to the provisions
of Section 5.7 of the Partnership Agreement), may amend any provision of the
Partnership Agreement necessary or advisable in connection with the
authorization of issuance of any class or series of Partnership Securities
pursuant to Section 5.6 of the Partnership Agreement; and

         WHEREAS, the General Partner deems it in the best interest of the
Partnership to effect this Amendment in order to provide for (i) the issuance of
the Class B Common Units to the General Partner in connection with the
contribution by the General Partner to the Partnership or its affiliate of all
of the membership interest in Williams Pipe Line Company, LLC pursuant to a
Contribution Agreement, dated as of the date hereof, among the General Partner,
the Partnership and Williams Energy Services, LLC and (ii) the redemption of the
Class B Common Units or, alternatively, for the exchange in accordance with the
terms described herein of the Class B Common Units for Common Units; and

         WHEREAS, the Partnership is concurrently entering into a Credit
Agreement, dated as of the date hereof, between the Partnership, Williams Pipe
Line Company, LLC and certain lenders whereby such lenders have agreed to loan
the Partnership and Williams Pipe Line Company, LLC, as co-borrowers, an
aggregate of $700 million;

         NOW, THEREFORE, the Partnership Agreement is hereby amended as follows:

1. Section 1.1 is hereby amended to add the following definition:

         "Bank Loan" means the loan evidenced by the Credit Agreement, dated as
of the date hereof, among Williams Pipe Line Company, LLC, Williams Energy
Partners L.P., Bank of


Exhibit 10.1 - Amendment 1 to Amended Restated LP Agreement - conformed copy

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America, N.A., Lehman Commercial Paper, Inc., Salomon Smith Barney, Inc., J.P.
Morgan Securities, Inc., and Merrill Lynch and Co., as the same may be extended,
amended and restated.

2. Section 1.1 is hereby amended to:

     (a)  add the following proviso to the end of the definition of
          "Outstanding":

                  "; and provided, further, that none of the Class B Common
                  Units shall be deemed to be Outstanding for purposes of
                  determining if any Class B Common Units are entitled to
                  distributions of Available Cash unless such Class B Common
                  Units shall have been reflected on the books of the
                  Partnership as outstanding during such Quarter and on the
                  Record Date for the determination of any distribution of
                  Available Cash."

     (b)  add the following paragraph to the end of the definition of
          "Subordination Period":

                  "Notwithstanding any of the provisions of clause (a) of this
                  definition, no Class B Common Unit shall be deemed Outstanding
                  in any Quarter if (1) such Class B Unit was issued after the
                  end of such Quarter or (2) such Class B Common Unit has been
                  redeemed by the Partnership prior to the Record Date for the
                  determination of any distributions of Available Cash from
                  Operating Surplus on the Class B Common Units for such
                  Quarter."

3. Section 5.2(b) of the Partnership Agreement is amended by changing the first
sentence thereof to read in its entirety as follows:

         (b) Upon the issuance of any additional Limited Partner Interests by
the Partnership (other than the issuance of the Common Units issued in the
Initial Offering or pursuant to the Over-Allotment Option), the General Partner
shall be required to make additional Capital Contributions equal to 2% of any
amount contributed to the Partnership by the Limited Partners in exchange for
such additional Limited Partner Interests, but only to the extent necessary such
that the General Partner's Capital Account is equal to 2% of the total of all
Capital Accounts following such issuance.

4. Article V is hereby amended to add a new Section 5.12 creating a new series
of Units as follows:

         Section 5.12 Establishment of Class B Common Units.

         (a)      The General Partner hereby designates and creates a series of
         Units to be designated as "Class B Common Units" and consisting of a
         total of [ ] Class B Common Units, and fixes the designations,
         preferences and relative, participating, optional or other special
         rights, powers and duties of holders of the Class B Units as set forth
         in this Section 5.12.

         (b)      Each Class B Common Unit shall be convertible from time to
         time, in whole or in part, at the option of the holders thereof, into
         one Common Unit from and after such date as the Partnership has been
         advised by the New York Stock Exchange that the Common

Exhibit 10.1 - Amendment 1 to Amended Restated LP Agreement - conformed copy   2

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         Units issuable upon any such conversion are eligible for listing on
         the New York Stock Exchange. The General Partner will promptly notify
         the holders of the Class B Common Units upon receipt of such advice.
         Upon written notice to the General Partner from the holders of at
         least a majority of the Outstanding Class B Common Units (a "Notice of
         Intent to Convert") given not earlier than one year after the date of
         this Amendment, the General Partner will use its reasonable best
         efforts to cause the Partnership to meet any unfulfilled requirements
         of the New York Stock Exchange for such listing, including obtaining
         such approval of the Unitholders as may be required by the New York
         Stock Exchange for the issuance of the Common Units, issuable upon
         conversion of the Class B Common Units. If, 120 days after the date of
         the Notice of Intent to Convert, the Common Units issuable upon such
         conversion have not been approved for listing on the New York Stock
         Exchange, then the terms of the Class B Common Units will be changed
         so that each Class B Common Unit will become entitled to receive
         quarterly cash distributions in an amount equal to 115% of the
         quarterly cash distribution amount payable with respect to each Common
         Unit. The Class B Common Units will not have the privilege of
         conversion except as provided in this Section 5.12.

         (c)      After the repayment in full of the Bank Loan, the Partnership
         may redeem the Class B Common Units for cash at any time by giving
         notice in writing to the holders of the Class B Common Units (a
         "Mandatory Redemption Notice") of the Partnership's intent to redeem
         the Class B Common Units. Any Outstanding Class B Common Units to be
         redeemed shall be redeemed as of the 30th day following date of such
         Mandatory Redemption Notice unless such day is not a Business Day in
         which case all such Outstanding Class B Common Units shall be redeemed
         on the next Business Day following such 30th day.

         (d)      Upon any request by the General Partner or any of its
         Affiliates to register all or any part of the Class B Common Units
         pursuant to Section 7.12, the Class B Common Units for which
         registration is so requested may be redeemed by the Partnership at its
         election. The Partnership shall exercise its option to redeem the Class
         B Common Units under this Section 5.12(d) by mailing written notice
         thereof to the holders of the Class B Common Units for which
         registration is so requested. Such notice shall be given not later than
         15 days after the receipt by the General Partner of such registration
         request and shall fix a date for redemption of such Class B Common
         Units not less than 30 nor more than 60 days after the date of such
         notice.

         (e)      Any redemption under Section 5.12(c) or Section 5.12(d) shall
         be for a cash redemption price equal to the Current Market Price per
         Common Unit as of the date fixed for redemption.

         (f)      Before any holder of Class B Common Units shall be entitled to
         receive any redemption payment or to convert such holder's Class B
         Common Units into Common Units, as the case may be, the holder shall
         surrender the Certificates evidencing the Class B Common Units, duly
         endorsed, at the office of the General Partner or of any transfer agent
         for the Class B Common Units. In the case of any such conversion, the
         Partnership shall, as soon as practicable thereafter, issue and deliver
         at such office to such holder of Class B Common Units one or more
         Certificates evidencing Common Units, registered in

Exhibit 10.1 - Amendment 1 to Amended Restated LP Agreement - conformed copy   3

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         the name of such holder, for the number of Common Units to which the
         holder shall be entitled. Such conversion shall be deemed to have been
         made as of the date of the surrender of the Class B Common Units to be
         converted, and the person entitled to receive the Common Units
         issuable upon such conversion shall be treated for all purposes as the
         record holder of such Common Units on said date.

         (g)      From and after a redemption date (unless default shall be made
         by the Partnership in providing money for the payment of the redemption
         price), the Class B Common Units redeemed shall no longer be deemed
         Outstanding, and all rights of the holders thereof as Partners in the
         Partnership (except the right to receive from the Partnership the
         redemption price) shall cease. Class B Common Units redeemed pursuant
         to Section 5.12(c) or 5.12(d) shall be restored to the status of
         authorized but unissued Units, without designation as to class.

         (h)      Except as otherwise provided in this Agreement, each Class B
         Common Unit shall be identical to a Common Unit, and the holder of a
         Class B Common Unit shall have the rights of a holder of a Common Unit
         with respect to, without limitation, Partnership distributions, voting
         and allocations of income, gain, loss or deductions; provided, however,
         that during the period in which any portion of the Bank Loan is
         outstanding, the Class B Common Units will not be paid a distribution
         of any kind. Upon the repayment in full of the Bank Loan, the holders
         of the Outstanding Class B Common Units will be entitled to receive a
         distribution of Available Cash equal to the distributions of Available
         Cash that were paid on or declared payable to the Common Units during
         the term of the Bank Loan. Except as otherwise provided in this
         Agreement, all Units shall vote or consent together as a single class
         on all matters submitted for a vote or consent of the Outstanding
         Units.

         (i)      The Class B Common Units will have voting rights that are
         identical to the voting rights of the Common Units and will vote with
         the Common Units as a single class, so that each Class B Common Unit
         will be entitled to one vote on each matter with respect to which each
         Common Unit is entitled to vote; provided, however, that the Class B
         Common Units shall not be entitled to vote and shall not be deemed
         outstanding for purposes of determining a quorum, with respect to
         matters in which the requisite vote is determined by New York Stock
         Exchange rules or New York Stock Exchange staff interpretations of such
         rules for listing of the Common Units; each reference in the
         Partnership Agreement to a vote of holders of Common Units shall be
         deemed to be a reference to the holders of Common Units and Class B
         Common Units.

         (j)      The Certificates evidencing Class B Common Units shall be
         separately identified and shall not bear the same CUSIP number as the
         Certificates evidencing Common Units.

Exhibit 10.1 - Amendment 1 to Amended Restated LP Agreement - conformed copy   4

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         IN WITNESS WHEREOF, this Amendment has been executed as of the date
first written above.

                                            WILLIAMS GP LLC
                                            General Partner

                                            By:  /s/ Don R. Wellendorf
                                               ---------------------------------
                                            Name:    Don R. Wellendorf
                                            Title:   Senior Vice President



Exhibit 10.1 - Amendment 1 to Amended Restated LP Agreement - conformed copy   5