EXHIBIT 5.1
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                                                                   July 28, 2004

Waste Connections, Inc.
35 Iron Point Circle, Suite 200
Folsom, CA  95630

            Re: Waste Connections, Inc. Registration Statement on Form S-8
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Ladies and Gentlemen:

            Reference is made to the Registration Statement on Form S-8 filed by
Waste Connections, Inc., a Delaware corporation (the "Company"), with the
Securities and Exchange Commission in connection with the proposed issuance and
sale or grant by the Company of an additional 2,250,000 shares of the Company's
common stock, par value $0.01 per share (the "Common Stock"). As counsel for the
Company in connection with the registration, we render the opinion set forth
below.

            We have examined, and are familiar with, originals or copies,
certified or otherwise authenticated to our satisfaction, of documents,
corporate records and other writings which we consider relevant for the purpose
of this opinion. We have also reviewed the Amended and Restated Certificate of
Incorporation, the Amended and Restated Bylaws and pertinent resolutions of the
Board of Directors of the Company. In addition, we have ascertained or verified
other facts which we deem relevant for the purpose of this opinion.

            In connection with this examination, we have assumed the genuineness
of all signatures on original documents, the authenticity of all documents
submitted to us as originals, the conformity to originals of all documents
submitted to us as copies thereof, and the due execution and delivery of all
documents where due execution and delivery are a prerequisite to the
effectiveness thereof.

            Based upon the foregoing, and such other legal considerations as we
deem appropriate, we are of the opinion that:

            The additional 2,250,000 shares of Common Stock proposed to be sold
or granted by the Company under the terms of the Company's 2004 Equity Incentive
Plan, when sold or granted and issued in accordance with the terms of the plan,
will be validly issued, fully paid and non-assessable.

            We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement.



                                             Very truly yours,


                                             /s/ SHARTSIS, FRIESE & GINSBURG LLP