EX-21 2 ttek-ex21x10012018xsingles.htm EXHIBIT 21
Exhibit 21

Subsidiaries of Tetra Tech, Inc.
NAME |  | JURISDICTION OF FORMATION
Advanced Management Technology, Inc. |  | Virginia
American Environmental Group, Ltd. |  | Ohio
America's Schoolhouse Consulting Services, Inc. |  | New York
ARD, Inc. |  | Vermont
Ardaman & Associates, Inc. |  | Florida
BIOCNG, LLC |  | New York
Coffey UK Limited |  | United Kingdom
Cornerstone Environmental Group, LLC |  | New York
Cosentini Associates, Inc. |  | New York
Delaney Crushed Stone Products, Inc. |  | New York
Foothills Indemnity, Inc. |  | Hawaii
Fort Point Associates, Inc. |  | Massachusetts
Glumac |  | California
Hydro-Ops LLC |  | Delaware
INDUS Corporation |  | Virginia
Integrated Justice Systems International, LLC |  | Delaware
Management Systems International, Inc. |  | District of Columbia
PRO-telligent, LLC |  | Delaware
Rooney Engineering, Inc. |  | Colorado
Tetra Tech Alaska, L.L.C. |  | Alaska
Tetra Tech Australia Pty Ltd |  | Australia
Tetra Tech BAS, Inc. |  | California
Tetra Tech Cape Canaveral, LLC |  | Florida
Tetra Tech CES, LLC |  | Washington
Tetra Tech Coffey Holding LLC |  | Delaware
Tetra Tech Coffey Holding Pty Limited |  | Australia
Tetra Tech Construction, Inc. |  | New York
Tetra Tech EC, Inc. |  | Delaware
Tetra Tech EMC, Inc. |  | California
Tetra Tech ES, Inc. |  | Delaware
Tetra Tech Executive Services, Inc. |  | California
Tetra Tech Expeditionary Operations, Inc. |  | Delaware
Tetra Tech Holding LLC |  | Delaware
Tetra Tech IC, Inc. |  | Alberta, Canada
Tetra Tech International, Inc. |  | Delaware
Tetra Tech MA, Inc. |  | Delaware
Tetra Tech MIMDU, LLC |  | Delaware
Tetra Tech New Martinsville, LLC |  | Delaware
Tetra Tech Technical Services, Inc. |  | Delaware
Tetra Tech Tesoro, Inc. |  | Virginia

Exhibit 21

Whalen & Company, Inc. |  | Delaware
Whalen Service Corps Inc. |  | Delaware