WYDOT Executive Staff

Darin J. Westby, P.E., CPM - Director


Darin Westby was named WYDOT Interim Director by Governor Mark Gordon in March, 2023 and was appointed Director in August, 2023.  

Previously, Westby was the Director of the Wyoming Department of State Parks and Cultural Resources, a position he held since 2016 after serving 15 years with the agency and 18 years in State government. He has more than 28 years of experience in the environmental, architectural, engineering, construction and management fields. Westby earned his bachelor's degree in Mechanical Engineering from the University of Wyoming and holds a Civil Professional Engineering license and a certificate in public management.

Darin has served on numerous community service boards including the Cheyenne Building Code Board of Appeals.  He has also served for nearly 30 years as a volunteer for Cheyenne Frontier Days, known as the World's Largest Outdoor Rodeo and Western Celebration. In that capacity, he's held a variety of positions including Committee Chairman (Executive Vice President), General Chairman (Chief Operating Officer), Chief Executive Officer and Board of Directors.  He is among the 2023 inductees in the CFD Hall of Fame.   

Westby’s personal mission statement is to be family focused and lead with a mirror and significant brand management.  

Raised in Casper, Darin has resided in Cheyenne with his wife Misha since 1994. They have three children, now grown.  

In addition to volunteering in the community, Darin enjoys boating and other outdoor activities.  In 2023 he and his family opened Westby Edge Brewing Co. in Cheyenne.  


Mark Gillett, P.E. - Chief Engineer

GillettMark.jpgWYDOT officials appointed Mark Gillett as Chief Engineer in June 2020. As Chief Engineer, he is responsible for the planning, design, construction and operation of the state’s surface transportation system.

Prior to serving as Chief Engineer, Gillett was Assistant Chief Engineer for Operations, a position he served in from October 2016 through June 2020. As assistant Chief Engineer for Operations, Gillett was responsible for all five districts in the field, as well as the State Construction, State Maintenance, Highway Safety, Traffic Design/Operations, Equipment, and Facility programs in Cheyenne.

Gillett also served as WYDOT’s District Engineer for District 4 from 2000 to 2016. District 4 is based out of Sheridan and provides services for the northeast part of Wyoming.

Gillett started working for WYDOT in May 1980 as an engineer I in Gillette. After that, he served as Resident Engineer in Lovell, Resident Engineer in Cody, Maintenance Staff Engineer in Cheyenne and District Maintenance Engineer for District 4 in Sheridan.

Gillett was born and raised in Rapid City, S.D. He received a bachelor’s degree in civil engineering from the South Dakota School of Mines and Technology.

Dennis Byrne - Chief Financial Officer

byrneDennisColor.jpgDennis Byrne is responsible for the financial and risk management operations of WYDOT. Those duties include the development of a financial and operational strategy, metrics tied to that strategy and the ongoing development and monitoring of control systems designed to preserve WYDOT assets and report accurate financial results.

Byrne previously served as the WYDOT Aeronautics administrator, a position he held from 2008 to 2016. In that position, Byrne was responsible for the state’s Airport Improvement Program, oversaw the disbursement of federal-aid funds for improving airport facilities, coordinated design of airport construction and maintenance projects, and managed flight services for the governor and other officials on state business.

Byrne graduated from the University of Wyoming in 1993 with a degree in economics, and he earned his Process Management Certificate from Colorado State University-Denver in 2002. With WYDOT, he has served on special committees dealing with geographic information systems and strategic planning.

Taylor Rossetti - Support Services Administrator

taylorColor.jpgTaylor Rossetti was appointed as the WYDOT Support Services administrator effective July 2016 and oversees Compliance & Investigation, Driver Services, Human Resources, Motor Vehicle Services, Office Services and the Training programs.

He began with the Wyoming Department of Transportation in 2007. Originally hired as a transit specialist, he held multiple positions within the Office of Local Government Coordination prior to being named the Local Government Coordinator in 2012.

Rossetti is a Rock Springs native and graduated from the University of Wyoming with a degree in health sciences. He has worked for non-profits, in sales, and was a branch manager for a finance company prior to his WYDOT career.

Nathan Smolinski - Chief Technology Officer

Smolinski, Nate_2022.pngNate Smolinski was appointed WYDOT's Chief Technology Officer in 2022 and oversees the department’s Emergency Communications/Telecommunications, GIS/ITS/TMC and Information Technology/Data Storage/Web Applications programs. In addition, Smolinski was designated by Gov. Mark Gordon as the 911 coordinator for the state of Wyoming. 

Smolinski started with WYDOT in fall of 2011 in the former Telecom department as a telecommunications specialist. He moved up the ladder, serving as senior telecommunications technician in Lander and Emergency Communications district supervisor in Sheridan. In the summer of 2016, Smolinski moved to Cheyenne for a promotion to WyoLink system support manager and, in 2019, emergency communications program manager.

He also serves as a representative for WYDOT and the state on a number of national boards and committees, including the Cyber Infrastructure and Security Agency National Conference of Statewide Interoperable Communications; the Federal Emergency Management Agency’s Regional Emergency Communications Coordination Working Group; and as the state point of contact for ATT - FirsNet’s Wyoming initiative.

Prior to his time with WYDOT in Wyoming, Smolinski oversaw a communications contracting company, installing networks and infrastructure for New York State Government Facilities.

Brian Olsen, P.E. - Aeronautics Administrator

OlsenBrianColor.jpgBrian Olsen was appointed Aeronautics administrator in May 2018. He oversees the distribution of state and federal funds for airport development through the state’s Airport Improvement Program, the design of airport construction and maintenance projects, air service development through the Air Service Enhancement Program, and manages flight services for the governor and other officials on state business.

A Rawlins native, Olsen earned a bachelor’s degree in Civil Engineering from the University of Wyoming in 2002. He started his engineering career at the Wyoming Department of Transportation in the Bridge Program. His interest in aviation led him to a position with The Boeing Company in Seattle, Washington, in 2004 as a structural engineer on the 747 program. In 2008, he returned to the Bridge Program and subsequently to the Aeronautics Division in 2010.

In his spare time, he enjoys spending time outdoors and traveling. 

Col. Tim Cameron - Highway Patrol Administrator

Cameron Tim Col..jpg

Col. Tim Cameron became administrator and commanding officer of the Wyoming Highway Patrol in January 2023.

With over 40 years of policing experience, Cameron is a proven leader with a wealth of knowledge and expertise. Prior to joining WHP, Cameron served an unprecedented four terms as the Sheriff of St. Mary's County, Maryland.

He earned an undergraduate degree at Johns Hopkins University and a postgraduate degree from Johns Hopkins University in Baltimore, MD. In addition to his degrees, Cameron is a graduate of the National Sheriff's Institute, the FBI's Law Enforcement Executive Development course, the Maryland Police and Corrections Training Commissions Leadership Challenge, the Executive Leaders Program at Naval Postgraduate School's Center for Homeland Defense and Security in California, and the Police Executive Research Forum's Senior Management in Policing Course at Boston University.

Cameron is also a member of various stakeholder groups and associations, working on crucial issues and committees like the Heroin and Opioid Emergency Task Force and the Emergency Management Advisory Council, among others.

Keith Fulton, P.E. - Assistant Chief Engineer for Engineering and Planning

FultonKeith.jpgKeith Fulton oversees the Bridge, Contracts & Estimates, Geology, Highway Development, Materials, Planning and Right-of-Way programs as WYDOT’s assistant chief engineer for engineering and planning.

Fulton previously served as the state bridge engineer from 2010 to 2016.

Fulton first worked for the Wyoming Highway Department during the summer of 1989 as a temporary employee based in Laramie. He joined the department on a permanent basis in early 1992 as an engineering analyst in the Bridge Program at Headquarters.

Fulton later served as a principal bridge engineer and then as assistant bridge engineer. Altogether, he has more than 30 years of service with the state, mostly with WYDOT.

A Riverton native, Fulton earned both bachelor’s and master’s degrees in civil engineering from the University of Wyoming. 

His professional affiliations include the Wyoming Engineering Society and the Cheyenne Engineers Club.  He and his wife Tracy enjoy traveling and spending time outdoors with their two daughters.

Tom DeHoff, P.E. - Assistant Chief Engineer for Operations

Dehoff-Tom-web.jpgTom DeHoff has been the Assistant Chief Engineer for Operations since August 2020.  He has over 30 years experience with WYDOT. 

DeHoff is responsible for all five districts in the field; and the State Construction, State Maintenance, Highway Safety, Traffic Design/Operations, Equipment and Facility programs in Cheyenne.

Prior to his appointment, DeHoff was the district engineer for District 1 in Laramie, a position he held from May 2016. 

He also served as District 1 District Construction engineer from August 2011 to May 2016, staff engineer with the Construction Office from October 2010 to August 2011, resident engineer in Cheyenne from November 1999 to October 2010, project engineer from April 1999 to July 1999, senior engineer from January 1996 to April 1999, engineer/analyst from January 1994 to January 1996, engineer from January 1993 to January 1994, senior engineer specialist from January 1992 to January 1993, senior engineer technician from June 1991 to January 1992, engineer technician from January 1991 to June 1991 and engineer assistant from May 1990 to January 1991.

DeHoff’s first few positions at WYDOT were with the Laramie Design Squad, which is a program open to students who are attending the University of Wyoming for engineering. DeHoff graduated from UW with a bachelor's degree in Civil Engineering.