 Due to the Great Depression , the soaring costs of the expansion became unmanageable . Construction on the first phase of the IND was already behind schedule , and the city and state were no longer able to provide funding . By 1930 , the line was shortened to between 125th and 34th Streets , with a turnoff at 34th Street and a crosstown connection there ; this line was to be complete by 1948 . The line above 32nd Street was to start construction in 1931 , with construction of a southern extension to Houston Street to commence in 1935 ; these segments would open in 1937 and 1940 , respectively . This scaled @-@ down plan was postponed in 1931 . By 1932 , the Board of Transportation had come up with another plan , which omitted a branch in the Bronx in order to cut costs . The new line 's southern terminus would be truncated to the Nassau Street Loop . 
