Wastewater disposal into the marine environment is one of the main factors leading to the deterioration of coastal water quality. Poorly managed disposal can lead to increased concentrations of nutrients, organic and inorganic pollutants, as well as alter levels of turbidity, pH and bacteria (Carey and Migliaccio, 2009; Beck and Birch, 2012; Cheung et al., 2015). An increase in the level of pollutants can have an impact on coastal ecology and biodiversity and affect the health of recreational users (Schwarzenbach et al., 2010; Burd et al., 2012; Eugenia et al., 2016; Boehm et al., 2017).

The Australia State of Environment Report (2016) identified a significant deterioration in a number of components of the coastal environment (Clark and Johnston, 2017). A key finding of the Coasts chapter highlights that the current degradation of the coastal environment is “tightly correlated” with human population, and agriculture or industrial development. These stressors may impact coastal systems in complex and synergistic ways across a variety of temporal and spatial scales. In addition, other key findings state that, “data are insufficient to assess many aspects of the state of the environment of the coast.” The “Coastal Waters” section of the chapter highlighted the two pathways for nutrients to enter the coastal waters. These were sewage outfalls and the diffuse sources, such as runoff. These inputs can lead to degraded states in the coastal environment such as eutrophication, harmful algal blooms, low-oxygen dead zones, the disruption of biogeochemical cycling and disturbance of the ecological balance of marine ecosystems (e.g. crown-of-thorns) (Clark and Johnston, 2017).

Providing a comprehensive understanding of nutrient and pollutant loads into the marine environment around Australia is difficult given the different sampling and reporting requirements. The lack of consistency across reporting methods exemplifies the lack of transparency or openness in governance, which can have negative consequences on Australia’s coastal environment. Australia is obligated to manage resources of National Interest and as a signatory to the Convention on Biological Diversity, is required to safeguard its biological diversity, as well as manage the impacts of nutrients on ecosystem function and structure (Aichi Biodiversity Targets (8)) (NRMMC, 2010). An improvement in reporting requirements that aligns with national and regional interests, MNES, transboundary pollution and environmental concerns is warranted.

In order to reduce water quality degradation, there is a need to increase communication between the relevant stakeholders and the general community. The effectiveness of science communication will enable the general public to make a sound choice regarding the environmental issues as well as helping the decision makers to improve the marine environment management (Mea et al., 2016). Public notifications, particularly in relation to water quality events, play an active role in managing health risks for both humans and the environment. However, public notification or mis-notification can be fraught with errors (Thoe et al., 2014). For instance, clean beaches can be closed inadvertently because managers may feel unsure of the spatial extent of water contamination. On the other hand, contaminated beaches may remain open, due to the time mismatch between sampling and notification (Pendleton, 2008). Around the world, programs have been developed to notify the public about water quality issues, for instance, the Beachwatch monitoring program in NSW, which was started in 1989 in response to community concern about sewage pollution washing up on Sydney’s beaches (Beder, 1991; OEH, 2019). However, communication practices among the programs are variable and lack formal evaluation of their effectiveness (Pratap et al., 2011).

The National Outfall Database (NOD), developed by the Clean Ocean Foundation (COF) in collaboration with States and Territories Governments, provides policy makers with a guide to help prioritise outfall reform and identify public and private sector opportunities for wastewater recycling (Marine Biodiversity Hub, 2015). In collaboration with the National Environmental Science Programme – Marine Biodiversity Hub, the NOD also provides Australian water authorities and the public an accessible database to help identify pollutant loads and assess any potential health and environmental impact risks of sewerage outfalls on the marine environment and surrounding communities. The NOD provides an unprecedented national collection of water quality data, collected by water authorities and Local Governments according to guidelines set out in Environmental Protection Authority (EPA) licenses. Given the NOD’s centralized collection of national scale water quality data, the opportunity to examine the comprehensive impacts of sewerage outfalls at regional scales becomes possible. The aim of the NOD was to facilitate cross-institutional data sharing among federal, state, local governments and the community to promote transparency and openness of governance for managing pollutants from WWTPs. The NOD also provides data and information that could be helpful for integrating infrastructure planning and decision making of sewage effluent impacts on marine environment.