Van Sant served as mayor of Baltimore from 1871 to 1875, during which time the current Baltimore City Hall massive construction project 1867-1875, was completed under budget and dedicated. He later declined to be a candidate for renomination.
As mayor of Baltimore from 1871 to 1875, Van Sant oversaw the completion of the city's new hall, which was built between 1867 and 1875 and was finished ahead of schedule and budget. He declined to seek another term as mayor.