Further south.  Chicago Harbor is downtown.  I am on Calumet River about 7 miles down river from Calumet Harbor.  Calumet Harbor is about 10 miles south of Chicago Harbor on L.Michigan in South Chicago.  This is the industrial corridor.  Both Chicago River and Calumet River-Sag Channel meet up downriver about 20 miles south and inland. Both locks are similar... Sector-gated controlling works.