Almost a dozen reports have been compiled in the past 20 years canvassing sea walls, marinas and boat ramps in a bid to create a safer and more vibrant area – all seemingly gathering dust in the city council offices. 

But the lack of progress has not been such a bad thing, according to Dr John Sherwood, who is charged with heading a technical reference group, which has developed three options. 

“People have said ‘they wasted money’, I don’t think they have,” he said.

“Without those reports you wouldn't be making informed decisions. Now we are, we are making decisions you can justify with data and that’s really important.”

Changing the breakwater area is a complex and emotive issue. Balancing environmental consequences with users’ expectations is difficult. Understanding the science of nature is critical.

Dr Sherwood said swell waves and long waves impacted the harbour. 

“Swell waves are the ones you see breaking on the shore,” he said. 

“They cause water to build up over in the Granny’s Grave area until its height is too great. It collapses creating what is called a long wave which is like a mini tide. 

“The swell waves, plus long waves, mean we exceed the Australian standard wave height for safe boat launching, of 0.2 metres, 45 per cent of the time.” 

Dr Sherwood said no real management options existed for long waves meaning upgrade options had to reduce swell waves’ impacts.  

He said waves hitting the existing boat ramp created a shoaling effect, which created a major hazard.

“The recommendation in option A is deepen the water around the ramp and to remove the shoaling effect with an open, mesh style structure, allowing the wave to pass through it,” he said. 

“That would allow safe launching 90 per cent of the time. The other 10 per cent of the time, the sea state outside may not be good enough to allow any type of boating.”

The concept would also include amenity upgrades, like floating pontoons and widening the ramp. 

Dr Sherwood said the other two options, a spur breakwater or a fully enclosed harbour, would significantly reduce the effect of swell waves, allowing safe launching 100 per cent of the time. 

“They would also include some upgrades to the boat ramp, more for amenity than anything else,” he said. 

“There could also be some other benefits, you could create some fixed moorings while not impeding on the existing swing moorings.

“With the enclosed marina we have to be mindful of seiching, which is where water starts slopping backwards and forwards within the harbour. That’s a design issue and something we need to be mindful of.”

Dr Sherwood said each of the options were not mutually exclusive, and elements from one could be added to the other at a later date. 

“What we need to understand is there will never be completely still water, we are on such a high energy coast with strange geography,” he said. “Still water is never going to be achieved.”