Meet Dave Thielen, PE
Principal Geotechnical Engineer

Electrical transmission corridors
Heavy rail
Bridges and roads
Reinforced walls and slopes

Portland, OR


Dave started his master’s degree in marine engineering and worked for a year at the Oregon State Wave Research Laboratory. But during this time the ’70s oil crisis hit. “All the oil companies were laying off ocean engineers, so I switched my major to geotechnical engineering and went to work for a big soil engineering firm on the west coast.”

That move launched Dave’s geotechnical career, and today he is a principal in GeoEngineers’ Portland office. Dave says he engineers the ground. “I help make the ground stable so things that are built on the ground or in the ground don’t move or fall down—such as bridges, hospitals, roads, big retaining walls, marine terminals and air traffic control towers.” His favorite part of working at GeoEngineers has been the opportunity to work with and get to know his clients, many of whom have become friends. He also enjoys working with his colleagues. “We have so many intelligent staff and staff that genuinely want to help our clients solve problems,” Dave remarks.

When Dave isn’t working, he enjoys sports, music, nature and building things. His wide-ranging interests include taking in Broadway shows and rebuilding antique tube radios. Dave cherishes spending time with his 20 nieces and nephews. “They all love Uncle Dave, who likes to hike with them, teach them how to tie trout flies and rebuild their bikes, and most importantly, help them with their math homework.”


Volunteer Videographer and Computer/Technical Support, Tigard/Tualatin School District Stage Productions, 1996 to present

Selected Presentations & Articles

  • "Mechanically Stabilized Earth Walls, Design and Review,” presented to the ASCE Oregon Geotechnical Section, 2007
  • "Transmission Tower Design and Lateral Pile Capacity,” a PacifiCorp regional broadcast, 2006
  • Contributing Member, Asphalt Pavement Association of Oregon ( APAO) publication committee for the Oregon Asphalt Pavement Design Manual, published 2003
  • Lecturer, Oregon State University, practicum classes for geotechnical and civil engineers, 2000, 2001, 2003, 2005 and 2006