THIS week’s big swells might have been heaven for board riders, but they’ve taken their toll on sections of our coast, most notably on Stockton beach from the child-care centre to the north and the surf life-saving club to the south.
Erosion has been a problem at Stockton for decades and after at least six studies of the situation since 1985, the NSW government and Newcastle City Council should have a good understanding of the prevailing forces.
The rock breakwall built in 1989 to reinforce the shore along Mitchell Street has had a stabilising effect, but a coastal processes study done in 2006 for the council found that erosion north of the breakwall had continued to be a problem.
It noted that the ocean waters off the Stockton Bight were deepening through loss of sand to the north, which tended to make for powerful swells hitting the beach.
Even so, Stockton is like most beaches in that it goes through long periods of accretion, or sand build-up, followed by short spells of erosion, such as we are experiencing now.
If enough sand is built up to compensate for the short bursts of erosion, then the beach remains more or less stable. If it doesn’t, then the coast moves inland. This time around, the damage was severe enough to wash away much of the erosion repair that the council had just finished at the SLSC.
As a long-term protection, Newcastle council had proposed a wave-calming rock groyne, but the NSW government refused to consider the $30-million proposal when it was dealing last year with the council over a new coastal management plan.
Not everyone will agree that building such a sea-wall is a good idea. The 2006 study notes that Stockton is already adversely impacted by the breakwalls at the harbour mouth, and building another one could have unintended consequences.
But as these would likely be well north of the town, in line with the prevailing northwards movement of the sand, such impacts may well be considered acceptable.
Without something to calm the waves – offshore reefs have also been suggested – the beach in front of suburban Stockton is likely to continue receding, taking man-made structures with it. In the short-term, the council will need to decide whether to protect its child-care centre building, or find somewhere else on the peninsula.