21st Century Transportation Workforce Development Act This bill directs the Department of Transportation (DOT) to establish a task force on developing a 21st-century surface transportation workforce. The task force must develop and submit recommendations and strategies for DOT to evaluate the current and future state of the surface transportation workforce; identify factors influencing individuals pursuing careers in surface transportation; address barriers to retaining individuals in surface transportation careers; identify and address potential impacts of emerging technologies on the surface transportation workforce; increase access for vulnerable or underrepresented populations; facilitate and encourage elementary, secondary, and postsecondary students in the United States to pursue careers in the surface transportation sector; and identify and develop pathways for students and individuals to secure pre-apprenticeships, registered apprenticeships, and other work-based learning opportunities in the U.S. surface transportation sector. The task force shall terminate upon submitting to Congress a report containing the recommendations and strategies.