Protecting the marine environment
The Upper Spencer Gulf is home to important and unique aquaculture areas, fisheries and marine nurseries .
Northern Water is being designed to avoid potential impacts where possible, and to mitigate, manage or offset impacts in line with regulatory requirements. This includes:
- positioning the seawater desalination plant inland and using underground tunnel boring to protect sand dunes and the unique coastal environment
- locating the seawater intake in sufficiently deep water to allow safe vessel passage and avoid mangroves, reducing impacts on valuable habitats
- designing the seawater intake to allow marine life to swim in, out and around the structure
- undertaking marine hydrodynamic modelling to understand water movement and inform the design of the outfall diffuser. Modelling shows the return water will disperse well before it reaches the Giant Australian Cuttlefish breeding area (35km north of Mullaquana Station).
Key marine investigations
We have engaged technical specialists across a range of key disciplines to undertake the following seasonal marine environmental studies, including:
- marine/intertidal investigations to collect baseline information on marine communities within the intertidal zone
- mangrove condition surveys to assess the mangrove forest health and structure
- benthic habitat and seagrass health surveys to study the health and location of seagrass and seabeds
- prawn, fish and crab larval surveys to understand their habitats, abundance and breeding patterns
- prawn recruitment survey to assess the abundance and size of young prawns in the area
- epibenthic fish, invertebrate and infauna surveys to identify bottom dwelling or sediment dwelling fish and invertebrates
- sea water quality monitoring to test site specific water quality
- vertical water profiling to measure water characterised at various depths and to understand the aquatic ecosystems
- marine hydrodynamic modelling (near-, mid- and far-field) to understand how the return water moves and disperses in the Upper Spencer Gulf informing diffuser design and impact assessments
- desktop ecotoxicity assessment to evaluate the return water
- ongoing risk assessments to further review the potential impact to the Cuttlefish Coast Sanctury Zone.