The underpass was originally waterproofed with polyurethane coating, which was not effective. The city tried injecting polyurethane resin in the cracks but that was not successful in keeping out the water. Finally they tried the Krystol Concrete Waterproofing System which worked.
Repairing the underpass took 14 months and the costs were paid by the contractors whose mistakes necessitated the repairs. The newly waterproofed underpass opened up in March of this year.
Read the full case study here.