Prior to joining HDR, Orrison was assistant vice president for service, design and performance with BNSF. He directed development of BNSF's network plans for operation of daily merchandise train service.

Orrison has more than 30 years of experience in the rail industry, holding senior positions in strategy, operations research, field operations and network planning. In 1997, he wrote the USDOT Surface Transportation Board Operating Plan for the CSX acquisition of Conrail. He also has held consulting positions to aid development of the 2020 plan for the Ports of Long Beach and Los Angeles and has worked on or served in an advisory role for projects in Mexico, Brazil, Rwanda and Tanzania.