Form: 10-K

Annual report pursuant to Section 13 and 15(d)

February 22, 2023

Exhibit 21.1

Subsidiaries of Select Energy Services, Inc.

Entity

    

State of Formation

Select Agua Libre Midstream, LLC

Delaware

Complete Energy Services, LLC

Delaware

SES Holdings, LLC

 

Delaware

Select Energy Services, LLC

 

Delaware

Peak Oilfield Services, LLC

 

Texas

Rockwater Energy Solutions, LLC

 

Delaware

SES Sub A, LLC

Delaware

SES Sub B, LLC

Delaware

SES Sub C, LLC

Delaware

Select Energy Solutions (RW), Inc.

Delaware

Navy Holdings, Inc.

Delaware

Navy Holdco, LLC

Delaware

New Heckmann Water Resources Corporation

Delaware

New Heckmann Water Resources (CVR), Inc.

Delaware

SES Intermediate Holdings, LLC

Delaware

Affirm Oilfield Services, LLC

Texas

Heckmann Water Resources, LLC

Delaware

Heckmann Water Resources (CVR), LLC

Delaware

NES Water Solutions, LLC

Delaware

Guard Drilling Mud Disposal, LLC

Delaware

China Water and Drinks, LLC

Delaware

Badlands Power Fuels, LLC

Delaware

Nuverra Ohio Disposal LLC

Delaware

1960 Well Services, LLC

Ohio

Badlands Power Fuels, LLC

North Dakota

Clearwater Three LLC

Ohio

Clearwater Five LLC

Ohio

Clearwater Solutions LLC

Ohio

HEK Water Solutions, LLC

Delaware

Nuverra Total Solutions, LLC

Delaware

Heckmann Woods Cross, LLC

Utah

Nuverra Rocky Mountain Pipeline, LLC

Delaware

Breakwater Energy Services, LLC

Texas

Breakwater Energy Partners, LLC

Texas

Breakwater Midstream, LLC

Texas

Big Spring Recycling System, LLC

Delaware

Landtech Enterprises, LLC

North Dakota

Badlands Leasing, LLC

North Dakota

Ideal Oilfield Disposal, LLC

North Dakota

Select Water Reuse, LLC

Delaware

Select Western Company of Texas, Inc.

Texas

International Western Company, Inc.

North Dakota

Benchmark Energy Products, LLC

Texas

Benchmark Distribution Services, LLC

Texas

Rockwater Energy Solutions Water Management, LLC

Delaware

Rockwater Northeast, LLC

Delaware

Rockwater West TX, LLC

Delaware

EnerMAX Services Holdings, LLC

Delaware

EnerMAX Services G.P. ULC

Alberta

EnerMAX Services Limited Partnership

Alberta

EnerMAX Services (U.S.) Inc.

Delaware

Rockwater Energy Solutions North Dakota, Inc.

Delaware

Rockwater Production Testing Ltd.

Alberta


Rockwater Energy Solutions Administrative Services, LLC

Delaware

Crescent Companies, LLC

Delaware