During the summer of 1972, a barge load of heavy construction equipment under tow to the James Bay Project on the eastern shore of James Bay became grounded on a shoal at the mouth of the Fort George River, only a few miles from its intended destination. Federal Commerce and Navigation Limited retained Foundation of Canada Engineering Corporation Limited (FENCO) to study the feasibility of removing the heavy equipment from the barge by an overice crossing. FENCO personnel visited the site in November and December, 1972, compiled the necessary environmental data and designed a crossing consisting of ice built up by flooding. Following the completion of the 100 ft wide (30.48 m) and 74 in. thick (1.88 m) bridge by Sainte-Marie Construction, the ice bridge was instrumented and tested prior to and during the unloading process. Parameters measured were thickness, width, temperature, ice soundness, and deflections. Tide readings were also taken.Loads of 70 t and heavy trucks were removed with no problem. Deflections were very small and cracking was confined to the tidal zone.