Exhibit 5.1

February 19, 2026

Select Water Solutions, Inc.

1820 N I-35
Gainesville, TX 76240

Ladies and Gentlemen:

We have acted as counsel for Select Water Solutions, Inc., a Delaware corporation (the “Company”), with respect to certain legal matters in connection with the preparation and filing of an automatically effective Registration Statement on Form S-3 (the “Registration Statement”) filed on or about the date hereof with the U.S. Securities and Exchange Commission (the “Commission”) in connection with the registration by the Company under the Securities Act of 1933, as amended (the “Securities Act”), of the offer and sale by the Company, from time to time, pursuant to Rule 415 under the Securities Act, of an indeterminate amount of (i) shares of Class A common stock, par value $0.01 per share, of the Company (the “Common Stock”), (ii) shares of preferred stock of the Company, par value $0.01 per share, in one or more series (the “Preferred Stock”) which may be issued in the form of depositary shares evidenced by depositary receipts (the “Depositary Shares”) and (iii) warrants for the purchase of Common Stock, Preferred Stock, Depositary Shares, or any combination of the foregoing (the “Warrants” and, together with the Common Stock, the Preferred Stock and the Depositary Shares, the “Securities”).

We have also participated in the preparation of a prospectus relating to the Securities (the “Prospectus”), which is contained in the Registration Statement to which this opinion is an exhibit.

In connection with the opinions expressed herein, we have examined, among other things, (i) the Fifth Amended and Restated Certificate of Incorporation and the Third Amended and Restated Bylaws of the Company, (ii) the Registration Statement, (iii) the Prospectus, and (iv) the records of corporate proceedings that have occurred prior to the date hereof with respect to the Registration Statement. We have also reviewed such questions of law as we have deemed necessary or appropriate. As to matters of fact relevant to the opinions expressed herein, and as to factual matters arising in connection with our examination of corporate documents, records and other documents and writings, we have relied upon certificates and other communications of corporate officers of the Company, without further investigation as to the facts set forth therein.

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In connection with rendering the opinions set forth below, we have assumed that (i) all information contained in all documents reviewed by us is true and correct; (ii) all signatures on all documents examined by us are genuine; (iii) all documents submitted to us as originals are authentic and all documents submitted to us as copies conform to the originals of those documents; (iv) the Registration Statement and any subsequent amendments (including additional post-effective amendments), will have become effective and comply with all applicable laws; (v) all Securities will be issued and sold in compliance with applicable federal and state securities laws and in the manner set forth in the Registration Statement and the prospectus supplement to the Prospectus; (vi) one or more prospectus supplements to the Prospectus will have been prepared and filed with the Commission describing the Securities offered thereby; (vii) a definitive purchase, underwriting or similar agreement with respect to any Securities offered will have been duly authorized and validly executed and delivered by the Company and the other parties thereto; and (viii) any securities issuable upon conversion, exchange or exercise of any Depositary Shares, Preferred Stock or Warrants being offered will have been duly authorized, created and, if appropriate, reserved for issuance upon such conversion, exchange or exercise.

Based upon the foregoing, and subject to the assumptions, qualifications, limitations, and exceptions set forth herein, we are of the opinion that:

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We express no opinions concerning the enforceability of indemnification provisions to the extent they purport to relate to liabilities resulting from or based upon negligence or any violation of federal or state securities or blue sky laws.

The foregoing opinions are limited to the Delaware General Corporation Law (including the applicable provisions of the Delaware Constitution and the reported judicial decisions interpreting these laws), and we are expressing no opinion as to the effect of the laws of any other jurisdiction, domestic or foreign.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the use of our name in the Prospectus forming a part of the Registration Statement under the caption “Legal Matters.” In giving this consent, we do not admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act.