This is a bridge over the Sanitary  and Ship Canal in Lemont.  It is located between the Lemont Avenue Traffic Bridge and the Cal Sag Sanitary Ship Canal Confluence.

BNSF RR Bridge over the Sanitary Ship Canal Lemont

BNSF RR Bridge over the Sanitary Ship Canal Lemont

BNSF RR Bridge over the Sanitary Ship Canal Lemont

BNSF Railroad Bridge over Sanitary Ship Canal Lemont

It is a Pratt through Truss swing bridge.  It features v-lacing and lattice on various built up beams.   It was built in 1898.  The builder was the Keystone Bridge Company in Pittsburgh, Pennsylvania.  Substructure contractor was McArthur Brothers and Winston Company.    Railroads using the bridge included ATSF and BNSF.  Total cost was $84,391.45  Total weight of iron and steel was 2,315,656 pounds.  Counterweight is 858,645 pounds.  It consists of one main span.  Its length is 259.6 feet.  The structure length is 398.5 feet.