CH2M Hill Companies S-8 POS Registration of securities for employees (post-effective amendment)

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Exhibit 23.5

Consent of Independent Auditors

        We consent to the reference to our firm under the caption "Experts" in Amendment No. 1 to the Registration Statement (Form S-8 No. 333-113160) and related Prospectus of CH2M HILL Companies, Ltd. dated April 21, 2004 and to the incorporation by reference therein of our report dated February 12, 2003 (except for Note 1, as to which the date is July 8, 2003 and except for Note 15, as to which the date is February 12, 2004), with respect to the financial statements of Lockwood Greene Engineers, Inc. and Subsidiaries included in the Current Report on Form 8-K/A of CH2M HILL Companies, Ltd. dated April 21, 2004, filed with the Securities and Exchange Commission.

By: /s/ERNST & YOUNG LLP

Greenville, South Carolina
April 21, 2004

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Consent of Independent Auditors