After leaving the office of governor on January 8, 1911, Bowerman moved to Portland, where he resumed the practice of law. He was reelected President of the State Senate but retired following the 1911 session. As a private citizen he actively supported Oregon's first statewide bond issue for highway construction, a $6,000,000 proposal. He also served as an active lobbyist for years at the State Legislature. He died in Portland in 1957.