Despite several changes of course, the ship proved unmanageable due to its insufficient speed relative to the current. In desperation the captain ordered 'full speed astern', at which point all control was lost. The vessel drifted towards the bridge midway between the central navigation span and the eastern shore, crashing into the pile capping of piers 18 and 19, bringing three unsupported spans and a 127 m section of roadway crashing into the river and onto the vessel's deck. The ship listed to starboard and sank within minutes in 35 m of water a short distance to the south. Seven crew members on the "Lake Illawarra" were trapped and drowned. The subsequent marine court of inquiry found that the captain had not handled the ship in a proper and seamanlike manner, and his certificate was suspended for six months.