EX-21 2 ttek-ex21q42022.htm EX-21
Exhibit 21

Subsidiaries of Tetra Tech, Inc.
NAME |  | JURISDICTION OF FORMATION
Advanced Management Technology, Inc. |  | Virginia
American Environmental Group, Ltd. |  | Ohio
ARD, Inc. |  | Vermont
Ardaman & Associates, Inc. |  | Florida
Axiom Data Science, LLC |  | Alaska
BlueWater Federal Solutions, Inc. |  | Delaware
Cosentini Associates, Inc. |  | New York
Glumac |  | California
Hoare Lea LLP |  | United Kingdom
INDUS Corporation |  | Virginia
Management Systems International, Inc. |  | District of Columbia
PRO-telligent, LLC |  | Delaware
Rooney Engineering, Inc. |  | Colorado
Tetra Tech BAS, Inc. |  | California
Tetra Tech Canada Holding Corporation |  | Canada
Tetra Tech Canada, Inc. |  | Canada
Tetra Tech Coffey Pty Ltd. |  | Australia
Tetra Tech Construction, Inc. |  | New York
Tetra Tech EC, Inc. |  | Delaware
Tetra Tech ES, Inc. |  | Delaware
Tetra Tech Executive Services, Inc. |  | California
Tetra Tech Holding LLC |  | Delaware
Tetra Tech Holdings Pty Ltd. |  | Australia
Tetra Tech Limited |  | United Kingdom
Tetra Tech Tesoro, Inc. |  | Virginia
Tetra Tech UK Holdings Limited |  | United Kingdom

Exhibit 21