The Wānaka Yacht Club is concerned collisions will be inevitable on the lake this summer if there is not decent water safety oversight.
Wānaka harbourmaster Jeff Donaldson has resigned after raising safety concerns with the Queenstown Lakes District Council and council contractor, Cougar Security Group, without success.
Cougar Security Group were appointed to oversee navigational safety on all of the district's waterways earlier this year.
Wānaka Yacht Club commodore Graham Berry said he was disappointed Donaldson felt compelled to resign, but he understood why when faced with a lack of support, particularly with a lot more motorised crafts on the lake.
"With the conflict in Roy's Bay - it's everywhere but it's concentrated here because you've got so many users in one place that the Harbourmaster has to step up. I feel sorry for Jeff, thrown under a bus to some extent," Berry said.
"We met with the harbourmaster and [Cougar Security Group] about three months ago ... Something's fallen between the cracks."
He was particularly concerned about the lack of visibility on the lake in the lead up to summer - he has not seen them since that meeting.
A visible presence helped people to remember the rules and meant they had someone to deal with situations where rules were broken or to educate people, he said.
While there was about 20 trailers on the lake shore on Tuesday, Berry said that would likely get to 300 within a couple of days and could get up to 1000 boats on the lake over peak summer.
"New people, new crafts, younger people combine that with not enough adult supervision, chuck in a bit of alcohol, then you've got conflict," he said.
"We've got away with it so far out of luck ... it's inevitable that we're going to have a bit of drama."
When asked what that could entail, Berry said "boats going too fast and hitting each other or a swimmer or a kayaker. Lots of near misses and so without policing, increases the probability of something bad happening."
People needed to remember to stick to five knots within 50 metres of the shore or another vessel, he said.
The club's safety boats were already picking up the slack and might need to ramp up its efforts this summer to fill a gap unless the issue was sorted, he said.
"Last Thursday night, our safety crew had to go and chase down a family and remind them politely that he's doing about 15 knots really close - actually to my boat ... that's how accidents happen and the guy had no idea. Didn't know the rules.
"Where we haven't got the service we thought we were going to get, we'll just have to step up. We do anyway. [The] Harbourmaster can't be everywhere but they need to be somewhere and around regularly."
He hoped Cougar Security Group would be able to attract their former harbourmaster back and provide enough support around him so he felt safe, Berry said.
When asked for comment, Cougar Security Group declined, instead referring all questions to the Queenstown Lakes District Council.
In a statement, Queenstown Lakes District Council regulatory manager Anthony Hall acknowledged the concerns of community members about the resignation.
"Not having a locally-based harbourmaster in the Upper Clutha at the present time is obviously disappointing, especially as we approach the holidays, but we have deliberately built resilience and capacity into the wider team for any unforeseen staff issues, particularly with the potential effects of Covid-19 in mind," Hall said.
"Public safety remains our priority and you can expect to see waterways officers out and about this summer, both at boat ramps sharing information to assist with self-compliance and handing out new information guides, as well as out on the water with jet skis.
"Deployment is always influenced by the weather and local demand but there will be the same level of service expected by the local community and visitors across Lakes Wānaka and Hāwea as well as Lake Whakatipu and all their associated rivers."
The council and its contractor, Cougar Security Group, worked closely with Maritime NZ on education and enforcement as well as certification of the contractor's vessels and staff training plans, he said.
Hall reminded boaties that there were various services overseeing waterways, including Maritime NZ, Coastguard, police and the harbourmasters, especially during emergency situations.
"With the busy holiday season about to begin it's a good opportunity to remind everyone that in any emergency situation people should first call 111 and ask for the police," he said.
"Boaties with a VHF radio should also know how to put out a mayday call on specific channels relating to their location. For non-emergencies, such as a broken-down vessel, Coastguard should be called on *500.
"The role of the harbourmaster and other council-managed waterways officers is education and ensuring users of lakes and rivers adhere to relevant water safety rules and bylaws such as the mandatory wearing of lifejackets on all vessels under six metres, speed limits in different waterways and so on.
"Any concerns about these can be reported to council by phoning 03 441 0499 or lodging a Request for Service via our website."
Jeff Donaldson has been contacted for comment.