Three new signs were placed near the Hawea Whitewater Park last week warning people about the dangers of becoming stuck around Camphill Rd bridge pylons while surfing.
There have been two near-drownings in the past three years involving surfers becoming tangled in the pylons.
In April, a man needed to be rescued when he became trapped under the water with his board, still tied to his leg, on one side of a pylon and him on the other side.
A similar accident happened about two years when another surfer needed to be saved by kayakers.
The signs, installed by the Queenstown Lakes district Council, advised surfers to attach their boards to their bodies or arms instead of their legs and to wear a full wetsuit or life jacket.
Queenstown Lakes District harbourmaster Marty Black said surfers had to obey the QLDC's navigation safety bylaw, just like everyone else, which meant wearing a life jacket or a full wetsuit.
Surfers should also consider helmets, Mr Black said.
Surfing on the river posed a lot more dangers than surfing in the ocean, because of the strong currents and rocks, he said.
''It will bite you and bite you hard,'' he said.
During the summer, the harbourmaster team would check the area often to make sure people were obeying the bylaw, Mr Black said.
''It comes down to personal responsibility and people being smart about it - but we will be around more just to make sure people are being sensible''
Other options for increased safety at the bridge had been considered, such as having a ladder installed on the sides of the pylons so people in trouble could possibly climb out, but for now nothing else would be installed.
''That doesn't rule anything out in the future but for now we want to see how the sign works.''
