Canada Geese (Nesting)

I spotted a pair setting up a nest about three weeks ago, and now this may be the same pair. Last year, a pair attempted to set up a nest at this very location, but it appeared that Ring-billed Gulls destroyed the eggs. This location is on top a pylon in the Chicago River behind the Civic Opera Building on the South side of the Washington Ave Bridge. Looks like they are using some netting some left behind. The location is near a dock where commuter from Metra Trains board water taxis.