Tweed River dredging begins
On the weekend, dredging of the Tweed River entrance began once again. Intermittent dredging of the entrance is part of the sand bypass project as not all the sand moving northward is captured by the sand pumps at Letitia Spit. During storm events, sand can settle as a bar at the entrance to the Tweed River impeding safe navigation.
Every few years the Tweed entrance gets dredged and the spoil dumped north of the Tweed. In the early years of operation, large volumes of dredged sand were used to restore the severely eroded southern Gold Coast beaches. Much of it was dumped into Coolangatta Bay, reducing its depth and also the wave energy reaching the bank.
Prolonged calm weather over the early to mid 2000's resulted in slower than predicted sand movement along the southern Gold Coast beaches, factors that contributed to the formation of wide beaches in Coolangatta Bay and at Kirra, plus accumulation of sand around Kirra Reef.
While recent studies have shown that the excess sand volumes are naturally dispersing from Coolangatta Bay, the concerns of surfers have led to changes in the operation.
The spoil from the current operation will be dumped in three, or potentially four, targetted locations:
- Offshore from Duranbah (36,000 cubic metres)
- Snapper Rocks east (54,000)
- Bilinga/Tugun (30,000)
- Fingal (30,000) - though it's subject to approval
In all, 150,000 cubic metres will be dredged. If Fingal doesn't meet approval the 30,000 will be spread evenly among the other three locations.
The operators aren't dumping any spoil within the bay, and they're also trying to avoid excess sand settling on the bank at Kirra, hence the offshore dumping at D'bah and bypassed load at Bilinga, while the Snapper east sand should smooth out recent corrugations in the Superbank.
Also, the sand dumped at Bilinga/Tugun will help with sand build up on the upstream side of the Palm Beach artifical reef, which is 40% complete.
The dredging will continue for approximately two months.