Complex sentence: The portion of the highway adjacent to the collapse (Jane Street north to 26th Street) came down first, in 1977, and the portion between 26th and 42nd Streets was demolished between November 1981 and the summer of 1982.
Split into simpler sentences: The portion of the highway adjacent to the collapse (Jane Street north to 26th Street) came down first in 1977. Next, the portion between 26th Street and 42nd Street was demolished between November 1981 and the summer of 1982.