Main and Clarkes Beach Dune Recovery Project

The aim of this project is the rebuilding of the Main and Clarkes beach dunes between Byron Bay Surf Life Saving Club and the Byron Beach Café

The work to take place is beach scraping, also known as sand harvesting. This process supports mother nature by speeding up the movement of sand from the intertidal zone to rebuild the dune face, which creates habitat for native plants and animals. Dune revegetation, fencing and public accessway management will be completed after the sand harvesting to support this work. 

Works will take 10 days during November 2022, pending finalisation of permits as well as natural processes such as tides, weather, swell and beach profile condition. This has been scheduled to best align with weather and nesting seasons as well as busy seasons for amenity use.

Beach scraping is the movement of small to medium quantities of sand from the lower part of the beach system to the dune, using mechanical means. Beach scraping does not introduce new sand to the system, but redistributes sand within the system, and can artificially speed up dune building (volume and height). The scope of the works is to gather sand from elsewhere on the beach to assist with the stabilisation and restoration of the dune system.

Beach ‘scraping’ is a very useful and cost effective technique for rebuilding dunes or restoring beaches. Over the years there have been many names for the beach ‘scraping’ technique, but the more descriptive term for the methodology is “Nature Assisted Beach Enhancement"(PDF, 95KB) .

Scraping accelerates the natural process of dune re-building by moving sand from the intertidal area of the beach and placing it on the dunes.

Council has undertaken beach scraping programs at New Brighton Beach north of Byron Bay on three formal occasions. Numerous historical scraping activities have also been completed in the past. Scraping works have been deemed a success, with the 2017 sand volumes still within the system and almost completely covered in vegetation.

The beaches further west in the embayment, of Cavvanbah and Belongil, have also experienced recent erosion as a result of storm events and natural sediment transport processes. There are steep dune escarpments in places, fallen trees, and loss or crumbling of coffee rock which is very similar to that experienced at Main and Clarkes Beach.

A significant volume of sand has recently entered the embayment, having bypassed Cape Byron. As this large pulse of sand moves through the embayment from east to west, the preceding erosion cell may temporarily make erosion worse at these beaches.

Council is monitoring the situation closely. However, there needs to be further build-up of sand reserves along this stretch of beach before dune management can be considered. As the sand within the embayment moves onshore during calmer wave conditions and the current and significant pulse of sand continues to move north westwards, Council may then consider replicating a similar beach scraping and dune restoration campaign in the future.

Beach scraping works with the natural coastal processes that redistribute sand within a sediment compartment through the action of waves, tides, and wind. Sand is transported onshore faster under calmer ‘beach rebuilding’ conditions, as small volumes of sand are removed from a shallow scrape zone within the intertidal zone. The volumes of sand being moved from the intertidal zone onto the upper beach are minimal in comparison to the amount of sand located within the surf zone, which moves freely via cross-shore and longshore sediment transport as a result of tides, wind and waves.

There are no immediate or long-term negative impacts expected to the beaches further west which are down-drift from this project. This is because of

• the small sand volumes being moved,
• the significant volumes of sand that have returned to the embayment,
• the natural beach rebuilding processes currently underway, and
• the natural onshore movement of sand anticipated as a result of the minor scraping works.

The currently reduced beach profiles of the western beaches of the bay are influenced by larger scale sediment transport processes, which are primarily driven by the function of headland bypassing around Cape Byron.

It is expected that the significant pulse of sand currently moving through the embayment will continue to migrate north westwards and contribute to the natural beach recovery in these areas.

The stretch of beach from Main Beach to The Pass is managed by several different agencies.  For more information download the map showing the area from Main Beach to the Pass: Main Beach to The Pass - Who Manages What(PDF, 277KB)

The persistent erosion trend experienced at Clarkes and Main Beach during 2020/21 is thought to be due to a general reduction in the littoral transport regime which transports sand in the zone close to shore from south to north around Cape Byron. This slowing of sand transport is from a possible reduction in frequency of moderate to large south to southeast swell events over the past few years up until winter 2020. While the sand supply remained semi-stationary at The Pass, there was a significant lack of sand levels at Main and Clarkes Beach during the December 2020 storm event.

Further detail and imagery can be found at Insights into erosion at Byron Bay, Australia by Bluecoast Consulting 

Coastal erosion is the wearing away of land by the action of natural forces. On a beach, this is the carrying away of beach material by wave action, tidal currents, littoral currents, or by deflation.

The landward limit of erosion in the dune system caused by storm waves is called the erosion escarpment. At the end of a storm the escarpment may be nearly vertical.

Coastal erosion usually occurs after one event and over a short period of time.

Coastal recession differs from erosion as it is the continuing landward movement of the shoreline over a specified period of time (i.e. years).

Beach scraping does not address long-term erosion (i.e. shoreline recession) and is not seeking to restore or reinstate the original pre-storm dune volumes. Beach scraping will rehabilitate the dune system through restoring only a small percentage of the original sand volumes to assist in the recovery of its form and function.

An apparent increase in sand supply around Cape Byron into the Bay has been observed since winter 2020.

Council has commenced preparation of Coastal Management Programs (CMPs) for its coastline. CMPs are a long-term strategy to guide Council and other stakeholders in the management of the coast. A CMP is an action plan to

• address coastal hazard risks,
• preserve habitats and cultural uses,
• encourage sustainable agricultural, economic and built development in the coastal zone,
• maintain or improve recreational amenity and resilience, and
• adapt to emerging issues such as population growth and climate change.