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                                                                     EXHIBIT 5.1

August 24, 2001

CH2M Hill Companies, Ltd.
6060 South Willow Drive
Greenwood Village, CO 80111-5142

Dear Ladies and Gentlemen:

You have requested our opinion with respect to certain matters in connection
with the filing by CH2M Hill Companies, Ltd., an Oregon company (the "Company")
of a registration statement on Form S-8 (the "Registration Statement") with the
Securities and Exchange Commission, including a prospectus included in the
Registration Statement relating to the sale of 1,000,000 shares of the Company's
common stock (the "Shares") which may be sold by the Company.

In connection with this opinion, we have (i) examined and relied upon the
Registration Statement and (ii) reviewed the Company's Restated Articles of
Incorporation and Restated Bylaws and the originals or copies certified to our
satisfaction of such records, documents, certificates, memoranda and other
instruments as in our judgment were necessary or appropriate to enable us to
render the opinion expressed below.

On the basis of the foregoing and in reliance thereon, we are of the opinion
that the Shares, when issued and sold in accordance with the Registration
Statement, will be validly issued, fully paid and nonassessable.

We consent to the reference to our firm under the caption "Validity of Common
Stock" in the prospectus included in the Registration Statement and to the
filing of this opinion as an exhibit to the Registration Statement and with the
securities laws administrators of each State in which registration or
qualification of the Shares is sought.

We do not express an opinion on any matters other than those expressly set forth
in this letter.

Very truly yours,

Holme Roberts & Owen LLP



/s/ Mashenka Lundberg
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Mashenka Lundberg, Partner