The shifting sands of North Creek

The dynamic sand shoals of lower North Creek are a key topic being considered in Ballina Shire Council’s Coastal Management Plan (CMP) for the estuary.

The development of a CMP is a five-stage process supported by the State Government. Stage 2 investigations are currently underway and include an investigation into the sources of poor water quality and drainage issues in the North Creek catchment. This involves a water quality monitoring program and hydrological modelling.

As part of these detailed studies it is also important to evaluate the build-up of sand in the lower reaches of North Creek. The biggest change to the shoals occurred in the early 1980s when the main tidal channel swapped from the eastern side of the shoals towards the centre, and later to the western side where it flows today.

A detailed survey of the shoals was undertaken in early 2018. This survey has recently been repeated (mid-2022), and the results have confirmed what many people suspect: the amount of sand is increasing.

Although the configuration of the sand shoals remains similar, the extent of sand exposed by a typical low tide has increased by around 10 per cent at the central sand flats compared with 2018, while the volume of exposed sand has grown by 45,000m³, nearly 50 per cent more than what was present in 2018.

Key changes over this time include the widening and build-up of the beach at The Serpentine, in-filling of the central shoals with higher sand banks, and the continued upstream progression of sand ‘waves’ as marine sand is pushed into the estuary by waves and tidal currents.

The case for dredging and other options, including the benefits and impacts of such activities, will be undertaken in Stages 3 and 4 of the CMP.

Community consultation will be carried out to compare historical observations, provide technical information, and determine the community’s aspirations and priorities for the management of North Creek. Stage 3 is anticipated to commence in 2023.

For more information visit ballina.nsw.gov.au/north-creek

Image: Mick Howland, Hydrosphere Consulting (c)