 The work to re @-@ grade and install drainage on Peach and Sassafras Streets coincided with the building of the station from 1925 to 1927 , and cost the city approximately $ 110 @,@ 000 . A temporary station was also erected at 14th and French Streets , and was used after the old Union Depot was demolished in 1925 until the completion of the new station . Union Station was dedicated on December 3 , 1927 , in a ceremony presided over by the presidents of the New York Central and Pennsylvania railroads , the mayor of Erie Joseph Williams , and former mayor William Stern who helped initiate the project . The Griswold Plaza Post Office , on the north side of 14th Street , opened in 1932 along with the tunnel connecting it to Union Station . 
