The Quinsippi Island Bridge over the Mississippi River in Quincy, IL, was built in 1899, originally as a railroad bridge used by Chicago, Burlington & Quincy Railroad (CBQ).  The bridge was built with six in-water masonry stone pier supports with an overall length of 650 ft.  In the 1980s, this railroad bridge was converted to a single-lane vehicular bridge.   After underwater inspections in 2014 and 2015, it was revealed that there was significant scour under one of the bridge piers from river flooding, compromising the structural integrity of the bridge.  The debate was to tear down and replace the bridge or construct an underwater repair.  In 2015, Synthetex was selected to repair the scour by providing our design input on the use of our grout bags and mats.  Our grout bags allowed the pumping of grout to fill the void below the pier.  Additionally, our HYDROTEX^® Articulating Block mats were used to cap the grout bags and surround the pier with a 15 ft wide flexible revetment.  This permanent repair saved the city of Quincy nearly five million dollars to replace the bridge. Synthetex products are an innovative way to cost effectively repair underwater scour of bridge piers, abutment and quay walls, outfalls, ports, off-shore pipelines, etc.