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Seattle Office

701 Fifth Ave, Suite 1600
Seattle WA 98104

Dallas Office

1301 Young Street, Room 840
Dallas TX 75202

DES provides comprehensive multi-disciplinary Project Management, Architecture and Engineering, and Acquisition Management Services. Our offices are located in Seattle and Dallas and our talented and experienced team is comprised of project managers, architects, engineers (civil, structural, environmental, mechanical, and electrical), contract specialists and lease contracting officers.

Director's Office

Staff MemberTitlePhoneLocation
Michael Weaver, PE Director (Civil) 206-615-2460 Dallas
Michelle Gettsy Administrative Officer 206-615-2471 Seattle
Carolyn Jones Secretary 214-767-3518 Dallas
Barbara Tulloch Administrative Officer 214-767-3493 Dallas
Andre Tyson IT Administrator 206-615-2787 Seattle

Project Management

Staff MemberTitlePhoneLocation
Denman Ondelacy, P.E. Deputy Director (Civil) 206-615-2451 Seattle
Frank Chua, P.E. Civil 206-615-2447 Seattle
Scott Fillerup, P.E. Mechanical 206-615-2781 Phoenix
Bruce Kemmet, PE Civil 214-767-8368 Dallas
Robb McClain, R.A. Architect 214 767-1322 Dallas
Matthew Mergenthaler, P.E. Civil 206-615-3795 Seattle
Tom Plummer, P.E. Civil 214-769-7708 Albuquerque
Michael Young, PE Civil 206-615-2489 Seattle

Architecture and Engineering

Staff MemberTitlePhoneLocation
Denman Ondelacy, P.E. Acting Deputy Director (Civil) 206-615-2451 Seattle
James Aberle, AIA Architect 214-767-4246 Dallas
Alex Gamble, AIA Architect/Sustainability 206-615-2533 Dallas
Guibin (Nick) Lu, SE Civil/Structural 206-615-2459 Seattle
Paul Ninomura, PE Mechanical 206-615-2095 Seattle

Acquisition Management

Staff MemberTitlePhoneLocation
Melissa Warmath Deputy Director / Chief of OEHE Acquisitions 214-767-3517 Dallas
Andrew Hart Supervisory Contracting Officer - Seattle 206-615-2453 Seattle
Jennifer Scroggins Supervisory Contracting Officer - Dallas 214-767-6613 Dallas
Nicholas Aprea Contract Specialist - Federal Acquisition 214-767-5255 Dallas
Kelly Britton Contract Specialist - Federal Acquisition 602-364-5081 Phoenix
Daniel Cotto Contract Specialist - Federal Acquisition 206-615-2790 Seattle
Drew Cranford Contract Specialist - Federal Acquisition 214-767-8675 Dallas
Jeffrey Haubenreiser Contract Specialist - Federal Acquisition 214-767-8588 Dallas
Toby Hayden Contract Specialist - Federal Acquisition 503-414-5524 Portland
Taylor Kanthack Contract Specialist - Federal Acquisition 206-615-2805 Seattle
Erik Lundstrom Contract Specialist - Federal Acquisition 206-615-2782 Seattle
Robert Miller Contract Specialist - Federal Acquisition 214-767-8589 Dallas
Matthew Sanders Contract Specialist - Federal Acquisition 206-374-7302 Seattle
Shaukat Syed Contract Specialist - Federal Acquisition 214-767-3934 Dallas
Thupten Tsering Contract Specialist - Federal Acquisition 206-615-2452 Seattle
Robyn Red Tomahawk Contract Specialist - Self-Governance 214-767-8587 Dallas
Crystalynn Rogers Contract Specialist - Self-Governance 214 767-0388 Dallas
Monica Weaver Contract Specialist - Self-Governance 240-460-1869 Dallas
Trina McBride Lease Contracting Officer 214-767-3999 Dallas
Malachi Nance Lease Contracting Officer 214-767-0422 Dallas
Ryan Siglock Lease Contracting Officer 214-767-1114 Dallas