The Slug

lom's picture
lom started the topic in Wednesday, 6 Jul 2011 at 9:14pm

Approval has been given for an artificial reef (sea slug) to be placed at North Cronulla. Is it possible Sydney could have it's own "superbank" with all it's pros and cons?
Here is the story from the St George Leader-
"Sand slug to aid waves
BY JIM GAINSFORD
07 Jul, 2011 04:00 AM
SURFING conditions will soon change at North Cronulla, after the green light was given to build an underwater sandbank, or ‘‘sea slug’’, to improve wave formation off the Prince Street seawall.
The sea slug will be created from 45,000 cubic metres of sand dredged from the Hacking River to clear navigation channels.

In what is believed to be a first for a Sydney beach, the sand will be strategically placed about 250 metres offshore in up to eight metres

of water to form a two-hectare rectangular mound.

And while the sandbank will break waves, it won’t break the bank, with construction to be carried out at no cost to Sutherland Shire Council.

The sea slug was designed by reef architect Andrew Pitt to influence the breaking patterns of waves along North Cronulla.

The decision to proceed comes after months of negotiation between the council, the dredging contractor McQuade Marine, the surfing community and the Bate Bay Sand Placement Committee, chaired by Leader chief photographer John Veage.

Previously, sand dredged from the Hacking River was dumped along the coast, Mr Veage said.

The committee believed that a strategically placed sand slug could be beneficial at North Cronulla.

‘‘We asked the council and the contractor if it was possible to strategically place it at a point that helps surfers and the beach,’’ Mr Veage said.

‘‘It will create a bombora which will bend the swell to create better breaking waves along the shoreline.’’

Historically, waves have broken in a straight line from North Cronulla to Elouera.

Mr Pitt, a design and landscape architect and researcher with Sydney University’s Coastal Study Unit, researched reefs on Australia’s east coast.

‘‘I looked at similar projects in the Netherlands and came up with case studies to see how it was configured to get improved surfing conditions and felt something similar could be done at Cronulla,’’ he said.

‘‘We are calling it a wave focusing sand slug. It will act like an antenna, but instead of attracting wave frequencies it will attract waves.’’

The dredging and sand placement is scheduled to take place in August."