Harbourmasters say they support a call for a blood alcohol limit for boaties, but it will be very difficult to enforce.
The Transport Accident Investigation Commission has made the recommendation in a report on a collision between a jetboat and a jet ski that killed two people on a Queenstown river in 2009.
The agency ruled alcohol was not a factor, but it was found on the jetboat and had been consumed in small quantities.
Tasman harbourmaster Steve Hainstock says a limit is a good idea, but testing would be hard to carry out.
Wellington harbourmaster Mike Pryce says a national pleasure boat safety forum lobbied the Ministry of Transport for a limit to be set about three or four years ago and the Government needs to hurry up and do it.