Mackenzie draws strength from the diverse talents and specialties of our staff. Click on the photos to get to know the members of our integrated team. Looking for a particular person, capability, or job function? Use the filter options or search field below.

Infrastructure

With today's limited funding to repair and replace our infrastructure backbone, the Mackenzie team continues to design our community's roads, parks, and utilities with a focus on the future and added value. Matt Butts leads Mackenzie's work in this market sector.

Brent Ahrend
  • PE
Transportation Planning
Senior Associate, Assistant Department Head - Transportation Planning

Brent Ahrend combines technical skills in transportation analysis and modeling with strong communication and demonstrated abilities to provide...Learn More

Matt Butts
  • PE
  • LEED AP
Civil Engineering
Associate Principal, Director of Civil Engineering & Transportation Planning

Matt Butts leads Mackenzie's Civil Engineering and Transportation Planning departments. In addition to managing infrastructure and sports and...Learn More

Gabriela Frask
Land Use Planning
Associate, Land Use Planning

Gabriela joined Mackenzie with experience working as a policy coordinator, as well as in corridor transportation planning. Clients benefit from...Learn More

Bob Frentress
  • PE
  • LEED AP
Civil Engineering
Senior Associate, Civil Engineer

Bob Frentress joined Mackenzie in 1993 after earning a B.S. in civil engineering from Portland State University. He provides street design, storm...Learn More

Ralph Henderson
  • PE
  • LEED AP
Civil Engineering
Senior Associate, Civil Engineer

Ralph Henderson is noted for his technical mastery. He has worked on a variety of projects from roadway improvements to athletic fields and parks...Learn More

Brian Hollenbach
  • PE
Civil Engineering
Civil Engineer

Brian Hollenbach brings a background of 16 years of experience on commercial, residential, and general civil engineering projects, including...Learn More

Todd Johnson
Land Use Planning
Associate Principal, Director of Land Use Planning

Todd Johnson has nearly two decades of planning experience. During that time, he has been active locally in regional planning and land use...Learn More

Dave Larson
  • PE
Civil Engineering
Associate Principal, Branch Manager - Vancouver, Civil Engineer

Dave Larson—both a licensed civil and traffic engineer—led the civil and traffic engineering departments at Mackenzie for more than 26 years....Learn More

Tim McGuire
  • PE
Civil Engineering
Senior Associate, Civil Engineer

Tim McGuire joined Mackenzie in 1986, after many years of experience with other firms. During his long tenure with the firm, his professional...Learn More

Brent Nielsen
  • PE
Civil Engineering
Senior Associate, Assistant Department Head of Civil Engineering

Brent Nielsen earned his B.S. and M.S., with an emphasis on geotechnical engineering, from Montana State University. Brent joined Mackenzie in...Learn More

Steven Tuttle
  • PLA
  • LEED AP
Landscape Architecture
Landscape Architect

A recent, strategic addition to the firm, Steven Tuttle brings considerable civic, commercial, mixed-use, and urban design experience to the...Learn More

Brian Varricchione
  • PE
Land Use Planning
Land Use Planning

Brian Varricchione joined Mackenzie's land use planning group in 2014, and has 15 years of professional experience. From 2005-2014, he served as a...Learn More

Tom Wright
  • LEED AP
Land Use Planning
Principal, Department Head - Land Use Planning

A principal of the firm, Tom Wright leads Mackenzie's land use planning group and oversees the firm's Vancouver office. Tom's career assisting...Learn More