Exhibit 5.1

November 6, 2019

1847432 Alberta ULC

Suite 4400, 500 Centre Street SE

PO Box 2850

Calgary, Alberta T2P 2S5

Ladies and Gentlemen:

We have acted as special counsel to 1847432 Alberta ULC, an Alberta unlimited liability company (“ULC”) and wholly-owned subsidiary of Encana Corporation, a Canadian corporation (“Encana”), in connection with the domestication in the State of Delaware (the “U.S. Domestication”) of Ovintiv Inc. (“Ovintiv”), a Canadian corporation to be formed, prior to the U.S. Domestication, from the amalgamation of ULC and another wholly-owned subsidiary of Encana to be organized under the laws of Canada, and the related Registration Statement on Form S-4 (the “Registration Statement”) of ULC, filed with the Securities and Exchange Commission pursuant to the Securities Act of 1933, as amended (the “Act”), and the rules and regulations thereunder

1847432 Alberta ULC

(the “Rules”). The U.S. Domestication will be effected pursuant to the provisions of Section 388 of the General Corporation Law of the State of Delaware, 8 Del. C. § 388, by filing a certificate of corporate domestication and a certificate of incorporation in respect of Ovintiv with the Secretary of State of the State of Delaware (the “Secretary of State”).

In connection with the U.S. Domestication, Ovintiv will assume (i) the Omnibus Incentive Plan of Encana Corporation, (ii) the Encana Corporation Employee Stock Option Plan, (iii) the Encana Corporation Employee Stock Appreciation Rights Plan, (iv) the Performance Share Unit Plan for Employees of Encana Corporation, (v) the Restricted Share Unit Plan for Employees of Encana Corporation, (vi) the Deferred Share Unit Plan for Employees of Encana Corporation, (vii) the Restricted Share Unit Plan for Directors of Encana Corporation, and (viii) the Deferred Share Unit Plan for Directors of Encana Corporation (collectively, including any schedules or appendices thereto, as amended from time to time, the “Encana Incentive Plans” and following such assumption by Ovintiv, the “Ovintiv Incentive Plans”), and each outstanding stock option (together with any associated tandem stock appreciation right), stock appreciation right, performance share unit, restricted share unit, deferred share unit, restricted stock and other share-based award granted by Encana pursuant to the Encana Incentive Plans (collectively, the “Encana Incentive Awards”) will be exchanged for an incentive award granted by Ovintiv (collectively, the “Ovintiv Incentive Awards”) pursuant to the Ovintiv Incentive Plans. The Ovintiv Incentive Awards will be subject to substantially the same terms and conditions as the Encana Incentive Awards, except, in the case of equity-based Encana Incentive Awards, the securities issuable upon exercise or settlement of the

1847432 Alberta ULC

Ovintiv Incentive Awards, as applicable, will be shares of common stock, par value $0.01 per share (“Common Stock”), of Ovintiv (or their cash equivalent) rather than common shares (“Encana Common Shares”) of Encana (or their cash equivalent).

You have asked us to furnish our opinion as to the legality of the securities being registered under the Registration Statement. The Registration Statement relates to the registration under the Act of 269,531,637 shares of Common Stock of Ovintiv, consisting of shares of Common Stock of Ovintiv to be issued to holders of Encana Common Shares in connection with the U.S. Domestication (the “Shares”) and shares of Common Stock of Ovintiv that may be issued pursuant to the Ovintiv Incentive Awards (the “Award Shares”).

In connection with the furnishing of this opinion, we have examined originals, or copies certified or otherwise identified to our satisfaction, of the following documents (collectively, the “Documents”):

1.    the Registration Statement;

2.    the Arrangement and Reorganization Agreement, dated as of October 31, 2019 (the “Arrangement and Reorganization Agreement”), between Encana and ULC, included as Exhibit 2.1 to the Registration Statement;

3.    a draft of the certificate of incorporation of Ovintiv to be filed with the Secretary of State, included as Exhibit 3.1 to the Registration Statement;

4.    a draft of the certificate of corporate domestication of the Ovintiv to be filed with the Secretary of State;

1847432 Alberta ULC

5.    a draft of the bylaws of Ovintiv to be adopted by Ovintiv, included as Exhibit 3.2 to the Registration Statement; and

6.    the Encana Incentive Plans and the forms of award agreements (collectively, “Award Agreements”) relating to awards granted under the Encana Incentive Plans.

In addition, we have examined such other certificates, agreements and documents that we deemed relevant and necessary as a basis for the opinions expressed below. We have relied upon the factual matters contained in the representations and warranties of Encana and ULC made in the Documents and upon certificates of public officials and officers of Encana and ULC.

In our examination of the documents referred to above, we have assumed, without independent investigation, the genuineness of all signatures, the legal capacity of all individuals who have executed any of the documents reviewed by us, the authenticity of all documents submitted to us as originals, the conformity to the originals of all documents submitted to us as certified, photostatic, reproduced or conformed copies of valid existing agreements or other documents, the authenticity of all the latter documents and that the statements regarding matters of fact in the certificates, records, agreements, instruments and documents that we have examined are accurate and complete.

Based upon the above, and subject to the stated assumptions, exceptions and qualifications, we are of the opinion that:

1.    When issued, delivered and paid for as contemplated in the Registration Statement and in accordance with the terms of the Arrangement and Reorganization Agreement, the Shares will be validly issued, fully paid and non-assessable; and

1847432 Alberta ULC

2.    When issued, delivered and paid for as contemplated in the Registration Statement and in accordance with the terms of the Arrangement and Reorganization Agreement, the Ovintiv Incentive Plans and any applicable Award Agreement, the Award Shares will be validly issued, fully paid and non-assessable.

The opinions expressed above are limited to the General Corporation Law of the State of Delaware. Our opinion is rendered only with respect to the laws, and the rules, regulations and orders under those laws, that are currently in effect.

We hereby consent to use of this opinion as an exhibit to the Registration Statement and to the use of our name under the heading “Legal Matters” contained in the proxy statement/prospectus included in the Registration Statement. In giving this consent, we do not thereby admit that we come within the category of persons whose consent is required by the Act or the Rules.

Very truly yours,

/s/ Paul, Weiss, Rifkind, Wharton & Garrison LLP

PAUL, WEISS, RIFKIND, WHARTON & GARRISON LLP