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                                                                  EXHIBIT 23.10
 
                       WILLAMETTE MANAGEMENT ASSOCIATES
 
                    8600 WEST BRYN MAWR AVENUE, SUITE 950-N
                         CHICAGO, ILLINOIS 60631-3505
                       773-399-4300 / (FAX) 773-399-4310
 
As independent appraisers, we hereby consent to the reference of our valuation
study, which was rendered to Quanta Services, Inc. to assist the Company in
determining the discount to be applied to the Common Stock issued in
connection with the Acquisitions and the Limited Vote Common Stock, and to the
use of our name as experts regarding that valuation study in the "Experts"
section of the Registration Statement.
 
/s/ Willamette Management Associates, Inc.
 
Willamette Management Associates, Inc.
December 19, 1997
 
 
 
 
  Portland, Oregon   Chicago, Illinois   McLean, Virginia   Atlanta, Georgia
