Smarter Cleaner Sydney Harbour
Sydney Coastal Councils Group (SCCG) and Parramatta River Catchment Group (PRCG) are partnering with CSIRO and the Sydney Olympic Park Authority (SOPA) on an innovative project that applies smart technology to help reduce stormwater pollution entering Sydney Harbour. Five councils are involved in this trial: Northern Beaches, Woollahra, Blacktown, City of Parramatta and Canterbury-Bankstown.
Channel 7 recently featured the Smarter Cleaner Sydney Harbour. Watch it here!
Issues with stormwater pollution and its management
Stormwater pollution is a significant problem for coastal waterways and the wider marine estate. Pollutants such as litter and sediment are washed off urban areas during rainfall and conveyed via the stormwater drainage network to receiving waterways. This pollution is not only unsightly but a threat to marine life and public health.
Trapped litter in Duck Creek, Granville (Source: SCCG)
A community survey conducted as part of the development of the NSW Marine Estate Management Strategy identified stormwater as the greatest threat to the marine estate. Similarly, stormwater pollution was identified as the highest priority threat to Sydney Harbour as part of the scoping of the Greater Sydney Harbour Coastal Management Program.
This problem has long been acknowledged. In response, local councils and other stormwater managers have for many decades installed gross pollutant traps (GPTs) on the stormwater network to trap pollutants before they reach the waterways. There are several thousand GPTs now in operation across Sydney and more continue to be installed.
Trash rack style GPT (Source: Stormwater NSW (2020), Guidelines for the maintenance of stormwater treatment measures)
Stormwater treatment technology has evolved considerably in this time. GPT maintenance practices, however, continue to rely on physical inspections and fixed schedules that determine when GPTs are cleaned, irrespective of how full the GPT actually is. That is, cleaning may occur before the unit is full, leading to higher maintenance costs, or may occur after the unit is full, meaning pollution may have bypassed the GPT.
Cleaning of a below-ground GPT (Source: Stormwater NSW (2020), Guidelines for the maintenance of stormwater treatment measures)
Improving GPT maintenance practice through smart technology
There is now an opportunity to employ the use of smart technology such as smart sensors, internet of things, digital twins and artificial intelligence (AI), to improve GPT maintenance practices.
Specifically, CSIRO has developed smart, low-cost AI-connected sensors that can be installed inside GPTs to determine when GPTs are approaching capacity and require cleaning. This will help optimize GPT maintenance regimes, reduce the risk of pollution bypassing the GPT and reduce work, health and safety risks associated with physical inspection.
Sensor attached to stormwater pit insert in the Clarence Plains Rivulet, Hobart (Source: CSIRO Marine Debris Team)
Camera attached to bridge in the Northern Beaches Council
In addition, AI-connected cameras can be installed over stormwater channels to monitor and estimate the amount of floating litter conveyed to receiving waterways. This will assist in catchment-based stormwater planning by, for example, quantifying pollutant loads, identifying pollutant hotspots within the catchment and evaluating the effectiveness of existing GPTs.
A partnership approach
After a successful initial trial of smart technology in Hobart, CSIRO is partnering with SCCG and PRCG to conduct a larger trial of this technology in Sydney. This involves the installation of up to about 80 sensors and cameras on GPTs and waterways across Sydney Olympic Park and seven local government areas within the Greater Sydney Harbour catchment, as well as the development of a web-based analysis, decision support and reporting tool.
The project is supported through the NSW Smart Places Acceleration Program with a $545,000 grant provided by the NSW Digital Restart Fund. SOPA is acting as the NSW state agency co-partner on this project given Sydney Olympic Park has one of the highest concentrations of GPTs in Sydney and the use of smart technology to improve asset management and reduce environmental impact aligns well with SOPA’s strategic direction.
Rain in Sydney Olympic Park (Source: Flickr user Alexey licensed under CC by 2.0)
Project Update
The project commenced in December 2022 and is expected to be completed in early 2024. The outcomes of the project will be considered in the preparation of the Greater Sydney Harbour Coastal Management Program as well as the implementation of the Greater Sydney Harbour Regional Litter Prevention Strategy. If the trial is successful, opportunities will be explored for expanding the application of smart technologies to other councils within the Greater Sydney Harbour catchment, and beyond.
The City of Sydney partnered with The University of Sydney’s Centre for Research on Ecological Impacts of Coastal Cities and the Royal Botanic Gardens & Domains Trust to create an aquatic corridor along the seawall foreshore of the City of Sydney local government area. This project delivered 
Bush regeneration contractors were engaged to remove weed species & encourage regeneration of native species in Gore Creek Reserve, focusing on endangered Littoral Rainforest and surrounds. Weed species to be controlled in the reserve included: ground asparagus, morning glory, madeira vine, Ehrharta, Trad, Privet & Ochna. Gore Creek Reserve Bushcare group and others have worked alongside the contractors with the aim of restoring bushland adjacent to their work sites. This project has been successfully completed and the legacy of the project will be maintained in the years to come through Lane Cove Council’s commitment of ongoing designated operational budget for the area, as well as the efforts of the local BushCare groups.
The North Palm Beach Dune Rehabilitation project rehabilitated 5.9ha (50% more than target) of highly degraded coastal dune within the North Palm Beach dune system. Managing weeds in the target site was important in tackling what was a reservoir of weeds threatening other rehabilitated and remnant vegetation. Over 5,000 native tubestock were planted. Completion of this project has reconnected a well-functioning native ecosystem and improved cological linkages between remnant native vegetation. This grant project has now been successfully completed and the legacy of the project will be maintained in the years to come through Northern Beaches Council’s commitment of ongoing designated operational budget for the area, as well as the efforts of local BushCare groups.
The project addressed major weed infestations within the project area. Two EECs were targeted: Themeda Grasslands on Coastal Headlands and Littoral Rainforest & Coastal Vine Thickets. Revegetation at 3 sites controlled exotic grasses at South Bilgola Headland, providing littoral restoration of the Bilgola Creek and restoring Coastal Clay Heath within an area heavily invaded by bamboo. A 
This project has brought together 11 physically connected Councils (Bayside, Cumberland, City of Canada Bay, City of Canterbury Bankstown, Georges River, Inner West, Randwick, Strathfield, City of Sydney, Sutherland Shire & Waverley) and Royal Botanic Gardens Sydney (RBGS) to coordinate a regional approach to fox management through a Fox Control Working Committee. SSROC have taken over management of this Committee to continue its work. A web portal, 
The Waverley Council LGA has lost 99% of the remnant vegetation that was present before European Settlement. This project is part of a larger effort by Waverley Council to halt this loss and improve the condition of the remnant from the current 4% up to 40% by 2020. To implement Council’s newly adopted 
and a reduction in invasive weeds, particularly along the coastal cliff-top heath vegetation communities. In combination with revegetation plantings the outcome has been an increased in size and resilience of the remnant vegetation communities. This grant project has now been successfully completed and the legacy of the project will be maintained for at least the next five years through Waverley Council’s commitment of ongoing designated operational budget for the area, as well as through the efforts of local BushCare groups.
The project has improved connectivity between three zones located along the Lane Cove R. starting from the Fullers Rd bridge next to the Lane Cove National Park moving south through O.H. Reid Reserve, the Chatswood Golf Course and Mowbray Park. Work primarily consisted of invasive weed removal to allow natural regeneration of indigenous species and this was supplemented with some plantings of indigenous plants to strengthen connection of work zones and other saltmarsh areas along the Lane Cove R. Willoughby City Council matched the contribution from Sydney’s Salty Communities grant to deliver this important project to rehabilitate this impacted ecosystem. 2,600 native tubestock were planted (800 more than target) and 8.9ha of weed treatment was undertaken. This grant project has now been successfully completed and the legacy of the project will be maintained in the future through Willoughby Council’s commitment of ongoing designated operational budget for the area, and the ongoing relationship they have developed with Chatswood Golf Club.
Through this project, waste oyster shell collected from commercial farms were processed and arranged to protect eroding riverbanks and to stabilise riparian and coastal vegetation. For the purposes of the Salty Communities Program, erosion control and vegetation enhancement is the primary objective. The project was carried out on behalf of 4 councils – Willoughby, Lane Cove, Sutherland Shire and City of Ryde, and involves education, with community groups engaged in reef building activities. Macquarie University is currently undertaking research into the performance of different oyster reef structures, & will build these project sites into their research program. 
Located in the Woronora River valley area (Woronora to Heathcote), the project has reduced the impacts of aggressive weed species, Weeds of National Significance & Key Threatening Processes on threatened flora and fauna species & three Endangered Ecological Communities of Coastal Saltmarsh, Swamp Oak Flood Plain Forest & Swamp Sclerophyll Forest on Coastal Floodplains. The activities have enhanced the 9 sites’ native biodiversity, increase public empowerment/knowledge and ensure past inappropriate urban development is ameliorated to ensure the ecosystem health of one of Sydney’s most unique Riverine systems. The project significantly exceeded its targets: pest management was undertaken in over 200ha of bushland (44% above target); weed treatment was implemented in 85ha (21% above target), and; over 2,100 native tubestock were planted (114% above target). This grant project has now been successfully completed and the legacy of the project will be maintained for at least the next ten years through Sutherland Shire Council’s commitment of ongoing designated operational budget for the area, as well as its long-term Woronora River Management Plan.
The remnant canopy of Balls Head has been affected by termites which appears to be having a serious ring-barking effect on many of these trees. To avoid generational loss of canopy this project involved research to compare treatment of arboreal termites (Nasutitermes walkeri) with appropriate control sites to compare tree responses and determine cause and effect for poor tree health. There has been a formalised monitoring regime, implemented by the 
This project supported an ongoing whole-of-lagoon approach, by focussing on the southern area of the refuge through restoring saltmarsh, creating habitat linkages and controlling vertebrate pest animals. This project has • Reduced the spread of high priority weeds; • Promoted a backyard habitat and garden escapes program; • Promoted the DY Fauna Fair as a celebration of the Wildlife Refuge for lagoon users; • Established a native seed bank using provenance from Dee Why Lagoon and neighbouring lagoon systems; • Produced a condition map of the bushland and saltmarsh, including mapping tree hollows. This project complements the ‘Dee Why Lagoon Wildlife Refuge Habitat Restoration Project’, a three year program funded through Environmental Trust.
This project aimed to control the growth and further spread of Salvinia, a water weed currently choking Warriewood Wetlands EEC, through introduction of cyrtabagous weevil. Prior to introduction, mechanical and physical weed treatment was planned, to reduce Salvinia cover to improve the probability of successful establishment of the weevil. However due to storm events, a large amount of Salvinia was washed away, delivering considerable savings for the project in mechanical clear. Unfortunately, subsequent storms also washed away many weevils. A 
This project restored a section of coastal remnant vegetation located on the Manly Scenic Walkway in Clontarf. The project site was comprised of Littoral Rainforest, listed in NSW as an Endangered Ecological Community. The works removed invasive species and revegetated with local provenance plants. The project site also has cultural significance, with several Aboriginal middens present. This afforded the opportunity to engage with the Aboriginal Heritage Office to develop a restoration project which enables the vegetation communities to be improved, whilst protecting culturally significant sites and developing interpretive signage and other educational elements. A community engagement program built the capacity of residents to value the local biodiversity and to engage with backyard habitat and garden escapes programs and undertake voluntary restoration activities on surrounding private properties.
This project engaged and tought community members to record the attributes of hollows and trees, and to monitor wildlife use of hollows. It has deliverd 
The project has delivered an improved wildlife corridor linking Endangered Ecological Communities of Curl Curl potentially affected by climate change, to the coastal corridor of Freshwater/McKillop Park, using the assistance of community and corporate volunteers and professional workers. Over 4,000 native plants, of over 30 different species, have been established to replace areas once degraded by Weeds of National Significance (WoNS) and other environmental weeds. A percentage of plants have been propagated from flora further north of this area, to improve climate change biodiversity resilience.
For the 23 Councils within the Sydney Coastal Councils Group (SCCG) and the Southern Sydney Region of Councils (SSROC) (including Ashfield; Bankstown; Burwood; Botany Bay; Canada Bay; Canterbury; City of Sydney; Hornsby; Hurstville; Kogarah; Leichhardt; Manly; Marrickville; Mosman; North Sydney; Pittwater; Randwick; Rockdale; Sutherland; Warringah; Waverley; Willoughby; Woollahra) existing mapping of habitat corridors, have been consolidated into one GIS layer, to identify opportunities for connectivity and contiguity across Council boundaries. 
The CSIRO SCCG partnership project, the 
A reference group was convened for the program, to provide further specialist technical input, guide and/or undertake research, review prioritisation and critique/evaluate sub-projects during development and execution. Expertise in Sydney’s coastal ecosystems, ecological restoration, urban biodiversity and organisational capacity-building provides critical advice to achieve project outcomes.
