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                                                                    EXHIBIT 3.17

                            CERTIFICATE OF AMENDMENT
                                     TO THE
                           CERTIFICATE OF DESIGNATION
                                       OF
                      SERIES A CONVERTIBLE PREFERRED STOCK
                                       OF
                              QUANTA SERVICES, INC.

         Quanta Services, Inc., a corporation duly organized and existing under
the General Corporation Law of the State of Delaware (the "Corporation"), does
hereby certify that:

         1.       The Certificate of Designation of Series A Convertible
Preferred Stock of the Corporation is hereby amended by deleting the first
sentence of Section 3(b) thereof in its entirety so that Section 3(b) reads in
its entirety as follows:

                  "(b)     Election of Directors. The directors of the
                           Corporation shall be elected as follows:

                                    i.       A majority of the outstanding
                  shares of Series A Preferred Stock and the shares of Common
                  Stock issued upon conversion thereof (the "Conversion Shares")
                  (to the extent permitted by applicable law) held by UtiliCorp,
                  voting exclusively and as a separate class, shall be entitled
                  to elect two of the total number of directors of the
                  Corporation, subject to the limitations set forth in
                  subsections 3(b)(ii), (iv) and (v) below.

                                    ii.      In the event that the ratio of the
                  total number of shares of Common Stock owned by UtiliCorp (on
                  an as-converted basis) to the total number of shares of Common
                  Stock outstanding, assuming full conversion of all securities
                  and full exercise of all outstanding rights, options and
                  warrants to acquire Common Stock (such ratio, "UtiliCorp's
                  Fully Diluted Ownership Ratio") is equal to or greater than
                  30%, then a majority of the outstanding shares of Series A
                  Preferred Stock and the Conversion Shares (to the extent
                  permitted by applicable law) held by UtiliCorp, voting
                  exclusively and as a separate class, shall be entitled to
                  elect three of the total number of directors of the
                  Corporation.

                                    iii.     To the extent any nominee of the
                  holders of the Series A Preferred Stock is not an officer of

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                  UtiliCorp, the Board of Directors of the Corporation shall
                  have the right to approve such nominee, such approval is not
                  to be unreasonably withheld. Only the holders of the Series A
                  Preferred Stock and the Conversion Shares (to the extent
                  permitted by applicable law) shall be entitled to remove from
                  office such directors nominated by the holders of the Series A
                  Preferred Stock and the Conversion Shares (to the extent
                  permitted by applicable law) or to fill any vacancy caused by
                  the resignation, death or removal of such directors.

                                    iv.      In the event that UtiliCorp's Fully
                  Diluted Ownership Ratio (A) is less than 10% or (B) UtiliCorp
                  sells or otherwise disposes of at least 50%, but less than
                  75%, of the total number of shares of Common Stock owned by it
                  on the Original Issue Date (on an as-converted basis), then a
                  majority of the outstanding shares of Series A Preferred Stock
                  and the Conversion Shares (to the extent permitted by
                  applicable law) held by UtiliCorp shall only be entitled
                  (voting exclusively and as a separate class) to elect one of
                  the total number of directors of the Corporation.

                                    v.       In the event that (A) UtiliCorp's
                  Fully Diluted Ownership Ratio is less than 5% or (B) UtiliCorp
                  sells or otherwise disposes of 75% or more of the total number
                  of shares of Common Stock owned by it (on an as-converted
                  basis), then a majority of the outstanding shares of Series A
                  Preferred Stock and the Conversion Shares (to the extent
                  permitted by applicable law) held by UtiliCorp shall have no
                  right (voting exclusively and as a separate class) to elect
                  any directors to the Board of Directors.

                                    vi.      The holders of Limited Vote Common
                  Stock, voting together as a single class, shall be entitled to
                  elect one member of the Board of Directors, but shall not
                  otherwise be entitled to vote in the election of directors of
                  the Corporation. Only holders of Limited Vote Common Stock
                  shall have the right to remove from office such director or to
                  fill any vacancy caused by the resignation, death or removal
                  of such director.

                                    vii.     Except as provided in Sections
                  3(b)(i), (ii), (iii) and (iv) above, the holders of Common
                  Stock and the holders of Series A Preferred Stock, voting
                  together as a single class, shall be entitled to elect all
                  members of the Board of Directors."

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         2.       The Certificate of Designation of Series A Convertible
Preferred Stock of the Corporation is hereby amended by deleting the final
parenthetical clause of Section 3(c)(v) so that Section 3(c)(v) reads in its
entirety as follows:

                  "(v).    Amend the Corporation's Certificate of Incorporation
                           or Bylaws or the organizational documents of a
                           subsidiary of the Corporation (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 containing in
                           each case any provisions which would adversely affect
                           or otherwise impair the voting powers, preferences or
                           other special rights or privileges, qualifications,
                           limitations or restrictions of the Series A Preferred
                           Stock."

         3.       The foregoing amendments were duly adopted in accordance with
the provisions of Section 242 of the General Corporation Law of the State of
Delaware.

         IN WITNESS WHEREOF, Quanta Services, Inc. has caused this Certificate
to be executed by Dana A. Gordon, its Vice President and General Counsel, on
this 10th day of February, 2003.

                                  QUANTA SERVICES, INC.

                                  By /s/ DANA A. GORDON
                                     -------------------------------------------
                                     Name:   Dana A. Gordon
                                     Office: Vice President and General Counsel

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