This source is from LostAllHope, so take it with a grain of salt: "The most important factor in suicide by jumping is height. Stone states that jumping from 150 feet (46 metres) or higher on land, and 250 feet (76 metres) or more on water, is 95% to 98% fatal."
Either way, 80m should be more than enough, even if you land on a grassy field. That's over 25 storys. The fact that it is called a suicide bridge and has no survivors you know of should tell you enough.