Take Utah Highway 9 to Sheeps Bridge Road at mile 17. At that milepost Mesa Road, which is signed, goes north, while Sheeps Bridge Road, which is unsigned, goes south. The government has just completed a new bridge over the Virgin River on Sheeps Bridge Road, and right after it you'll turn right on a double-track and park 0.2 miles (~320m) down it at the rim of the Virgin River. Jumping spots abound.
I do not know of anyone jumping from the bridge itself. The spot simply has the name bridge in it because it is near a bridge. The bridge itself is not from where the jumps are made, rather from rocks nearby. I don't know if the bridge is ideal for jumping as the water level here often fluctuates. I think I should mention this , as the water level here is not always high enough for safe jumping into it.
The picture is very legitimate. I got it from a close friend of mine. Without getting into too much detail, I can assure you that it is authentic.