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                                                                   EXHIBIT 10.48

                               AMENDMENT NO. 1 TO
                       SETTLEMENT AND GOVERNANCE AGREEMENT

         This Amendment No. 1 to Settlement and Governance Agreement (this
"Amendment") dated as of November 20, 2002 but effective as set forth below is
entered into by and between Quanta Services, Inc. ("Quanta") and Aquila, Inc.
("Aquila").

                                    RECITALS

         WHEREAS, Quanta and Aquila have entered into that certain Settlement
and Governance Agreement dated as of May 20, 2002 pursuant to which the parties
agreed, among other things, that the board of directors of Quanta shall consist
of ten directors; and

         WHEREAS, Quanta and Aquila desire to amend the Settlement and
Governance Agreement (the "Agreement") in the manner set forth in this
Amendment.

         NOW, THEREFORE, the parties hereto hereby agrees as follows:

1.       Definitions. Capitalized terms used and not otherwise defined herein
have the meanings set forth in the Agreement.

2.       Amendment. Section 2.06 of the Agreement is hereby amended and restated
in its entirety to read as follows:

                  "The Board of Directors shall consist of the number of
                  directors as determined pursuant to the Governing Instruments.
                  Any vacancy on the Board of Directors caused by the
                  resignation or removal of a director shall be filled
                  immediately upon the direction of the Person entitled under
                  the Governing Instruments or this Agreement to appoint the
                  director who resigned or was removed. If the vacancy is a
                  member of the Independent Committee, the individual shall be
                  selected to fill the vacancy in accordance with Section
                  2.03(b)(i) hereof. In addition, as long as the outstanding
                  shares of Series A Preferred Stock represent 10% or more of
                  the outstanding Common Shares (assuming conversion of the
                  Series A Preferred Stock), then approval by two-thirds of the
                  then-outstanding shares of Series A Preferred Stock, voting
                  together as a single class, is necessary before the Company
                  may amend its Governing Instruments or the organizational
                  documents of a subsidiary of the Company (including the filing
                  of a certificate of designation), in each case as amended, or
                  file with any governmental authority any resolution of the
                  Board of Directors of the Company containing in each case any
                  provisions which would increase the number of directors of the
                  Company to a number greater than 12)."

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3.       Documents Otherwise Unchanged. Except as herein provided, the Agreement
shall remain unchanged and in full force and effect, and each reference to the
Agreement shall be a reference to the Agreement as amended hereby and as the
same may be further amended, restated, supplemented or otherwise modified and in
effect from time to time.

4.       Effectiveness of Amendment. This Amendment shall become effective
immediately after the approval by the Company's stockholders of (i) the
convertibility of the Company's Series E Preferred Stock, par value $0.00001 per
share (the "Series E Preferred Stock") and the issuance of up to 24,307,410
shares of the Company's common stock, par value $0.00001 per share, (subject to
adjustment) upon conversion of the Series E Preferred Stock and (ii) the
amendments to the Certificate of Designation, Rights and Limitations of the
Company's Series A Preferred Stock, par value $0.00001 per share (the "Series A
Preferred Stock"), to (a) delete the requirement that the authorized number of
directors on the Company's Board of Directors be set at ten members and (b)
eliminate the ability of the holders of the Series A Preferred Stock to vote,
separately as a class, on any increase in the authorized number of directors on
the Company's Board of Directors beyond ten members.

5.       Binding Effect. This Amendment shall be binding upon and inure to the
benefit of the party hereto and its successors and assigns.

6.       Governing Law. This Amendment shall be governed by and construed under
the laws of the State of Delaware (without regard to conflict of laws
principles), all rights and remedies being governed by said laws.

                            [signature page follows]

                                     - 2 -

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         IN WITNESS WHEREOF, the undersigned have duly executed this Amendment
No. 1 to Settlement and Governance Agreement as of the date first written above.

                                           QUANTA SERVICES, INC.

                                           By: /s/ DANA A. GORDON
                                               ---------------------------------
                                           Name:  Dana A. Gordon
                                           Title: Vice President

                                           AQUILA, INC.

                                           By: /s/ LESLIE J. PARRETTE, JR.
                                               ---------------------------------
                                           Name:  Leslie J. Parrette, Jr.
                                           Title: Senior Vice President, General
                                           Counsel, and Secretary