This project determined the ecological effect of coastal wastewater treatment plant (WWTP) outfalls in two different coastal settings. Treated effluent, seawater, and marine sediments were collected from two WWTP outfalls located in South Australia (Glenelg & St Kilda). This is a shallow and retentive receiving environment and may accumulate effluent contaminants. Additionally, sediments were collected from another WWTP outfall in New South Wales (Malabar). This deep-water outfall discharges into a highly dispersive environment and offers a point of comparison for contaminant retention with the outfalls located in South Australia. Work focused on five contaminants that water quality managers had identified in previous NESP MaC work (Project 1.16) as being highly important: nutrients and metals (traditional effluent pollutants); and antibiotics, per- and poly-fluoroalkyl substances (PFAS), and microplastics (contaminants of emerging concern). This record describes the results from the sediment sampling component of this study. Results from the effluent and seawater sampling are described separately by the record 'Effluent and seawater sampling data from wastewater treatment plant outfalls' (https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/00c3e9a2-5d2f-44de-9c30-00f4af385b6a). Data is currently under embargo, to be released in January 2026.

This project determined the ecological effect of coastal wastewater treatment plant (WWTP) outfalls in two different coastal settings. Treated effluent, seawater, and marine sediments were collected from two WWTP outfalls located in South Australia (Glenelg & St Kilda). This is a shallow and retentive receiving environment and may accumulate effluent contaminants. Additionally, sediments were collected from another WWTP outfall in New South Wales (Malabar). This deep-water outfall discharges into a highly dispersive environment and offers a point of comparison for contaminant retention with the outfalls located in South Australia. Work focused on five contaminants that water quality managers had identified in previous NESP MaC work (Project 1.16) as being highly important: nutrients and metals (traditional effluent pollutants); and antibiotics, per- and poly-fluoroalkyl substances (PFAS), and microplastics (contaminants of emerging concern). This record describes the results from the wastewater (effluent) and sea water sampling component of this study. Results from the sediment sampling are described separately by the record 'Sediment sampling data from wastewater treatment plant outfalls' (https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/7130f946-c629-416e-99be-66ab53e885d7). Data is currently under embargo, to be released in January 2026.