Background - Tweed River Entrance Sand By-Passing
The Tweed River Entrance Sand By-Passing Project (TRESBP) is a joint scheme
by the New South Wales (NSW) and Queensland Governments, to intercept coastal
sand moving towards the entrance of the Tweed River in northern NSW and southern
Queensland, Australia and move it up the coast in order to meet the following
project objectives:
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To establish and maintain a clear navigation channel at the entrance to the Tweed River.
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To achieve a continuing supply of sand to the placement areas (southern Gold Coast beaches) at a rate consistent with natural drift rates.
The sand by-passing
system comprises of a sand collection jetty with an overall length of 450
metres constructed perpendicular to Letitia Spit beach. The system
has been designed to operate with up to five jet pumps working together at
the same time. The sand slurry produced is transported through a flume to
a slurry pit located on shore, which is then pumped through a 400 mm steel
pipeline under the Tweed River, to one of two fixed and two temporary outlets
in northern New South Wales and southern Queensland beaches. An excellent overivew of the sand by-passing project, including current
information about operatin of the system, is provided at the TRESBP
web site.
The Water Research
Laboratory (WRL) is undertaking this coastal imaging project to assist
the TRESBP Team to monitor and manage the beaches in the vicinity of the
Tweed River Entrance. Digital images of the coastline are being captured
every daylight hour by a total of sixteen cameras, mounted on the roof of
three apartment buildings, and a fourth site atop the Captain Cook Memorial
Lighthouse, Point Danger. These images are analysed at WRL, to monitor
and quantify beaches changes.
