Boats in the Queenstown Lakes district cannot exceed a speed of 5 knots within 200m of the shore. However, several Wanaka locals using Penrith Beach during the peak holiday period reported boats travelling at speed among swimmers, Queenstown Lakes district harbourmaster Marty Black said.
''The beauty of Wanaka is that people can ski where they like, providing they have consideration for other users.
''It appears that a few people have abused that, as we have had a number of complaints.''
While there was nothing to stop boaties launching from the beach, they were required to wait until they are 200m from the shore before accelerating, Mr Black said.
It is the first time there has been an issue with space-sharing at Penrith Beach, an area which has been particularly popular with lake-users this summer.
Mr Black hoped the buoy would allow all swimmers and boaties to continue to use the area safely.
''We don't want to have to put ski lanes all around the lake,'' he said.
Boaties who breached the 5-knot rule could be issued with an instant $300 fine. No-one in the district had been fined yet this summer, Mr Black said.