Dailan Pugh, Byron Bay
How can it be that 42 years after the problem was identified that there can be a panic when the coastal dunes start eroding at Clarkes Beach?
We are in a mess with coastal erosion, despite a 1978 Public Works Department Study identifying the cause as a net sand deficit, with less sand entering the bay than is being carted out of it by northwards littoral drift. After considering the full gambit of options, Council adopted the policy of planned retreat in 1986.
Since then the problem of rising sea levels and intensifying storms, owing to climate heating, have become apparent, with seas likely to rise by over a metre by the end of this century.
For each metre rise in sea levels, sandy coasts need to retreat 50–150m inland to maintain equilibrium. This has compounded the existing problem.
Since 1978 millions have been spent on coastal studies, and years spent preparing failed coastal plans, and we are still resorting to knee jerk reactions and spending fortunes undertaking temporary works. The simple truth is that if we pay a fortune putting in protection works to stop the dunes eroding, then the beach will erode in front, so we end up with just walls and no beach. In fact, the refraction of waves off the walls increases beach erosion, and the erosive force is transferred to the end of the walls (as can be seen at Belongil).
If we want beaches in the future (and Byron’s are worth millions in tourism revenue) we either have to allow the coast to retreat inland over time, or use sand replacement to maintain an artificial beach in front of them.
This is no mean feat in an era of rising sea-levels, given that if we want to raise the beach by a metre we have to raise the sea-bed by the same amount out to the limit of wave, storm, and current influences on sand movement.
Two sand replacement proposals have been advanced: A 2006 study identified that an initial volume of 2.85 million m3 could be dredged from a sand lobe in front of Cape Byron, barged to the coast and spread with bulldozers on beaches, in 2006 dollars costing $18 million and taking five months (7 days a week, 24 hours a day). They estimated this may, at best, last 25 years before having to be topped up, though it could be lost in a single cyclone.
In 2016 the proposal was to suck 50–80,000 m3 of sand per annum from Cosy Corner and pump it over to Clarkes Beach, at a cost of over $11 million for 20 years. This would rob Wategos and The Pass of sand and could alter the surf breaks. Both these options were objected to by the community and rightly rejected by Council.
So with no source of sand, in 2016 Council proposed to the government that they be allowed to build walls at Belongil, and just watch as the beach eroded from in front of them. The NSW government rejected this option.
So here we are, 42 years after the problem was identified, with no plan in sight. Rest assured that with climate heating gaining momentum and sea levels rising faster – the erosion will worsen.
Do we allow the beach to retreat inland as seas rise, or do we block it off and watch our beaches disappear, knowing that it is only a matter of time before expensive coastal protection works are overwhelmed?