Water Pollution's Early Days In Australia

Water pollution is a pressing issue in Australia, with a range of sources contributing to the contamination of water bodies. While it is challenging to pinpoint the exact timeframe when water pollution began in the country, it has likely been an ongoing issue for several decades. The diverse causes of water pollution in Australia include industrial wastewater, agricultural runoff, sewage systems, and plastic pollution. The discharge of toxic chemicals, oils, and metals from industries, as well as the improper disposal of household wastes, have all played a role in degrading water quality. Additionally, agricultural practices, such as excessive fertiliser and herbicide use, have negatively impacted waterways, particularly the iconic Great Barrier Reef. Recognising the severity of the problem, the Australian government has implemented various measures, including the National PFAS Position Statement endorsed by multiple states and the release of updated guidelines for freshwater and marine water quality in 2018.

Plastic pollution

The plastic crisis is not limited to Australia's borders, as significant volumes of plastic waste are transported across jurisdictions as waste exports and drifting ocean plastics. A notable disruption in the global plastic waste trade occurred in 2017 when China banned the import of large volumes of plastic waste, leading to neighbouring lower-middle-income countries (LMICs) receiving this rejected waste. These LMICs often lack the infrastructure to manage this influx of plastic waste, leading to an increased risk of plastic pollution.

The impact of plastic pollution on the environment is severe, with up to 145,000 tonnes of plastic entering Australia's environment each year. This pollution is found not only on beaches but also on land and in marine environments, endangering marine wildlife and even entering the food chain.

However, there are positive signs in the fight against plastic pollution in Australia. A study by Australia's national science agency, CSIRO, found that plastic pollution on Australia's coasts decreased by 29% between 2013 and 2022. This improvement is attributed to local governments' improved waste management and increased community involvement in clean-up activities and surveillance programs. Additionally, six out of eight states and territories have introduced laws banning some of the most harmful single-use plastics, with more laws in development.

To further address plastic pollution, Australia needs better governance and increased investment in reducing fossil fuel-based plastic production and improving waste management infrastructure. The CSIRO's Ending Plastic Waste Mission aims for an 80% reduction in plastic waste entering the Australian environment by 2030. Australians can also play a role by choosing products with minimal plastic packaging, using reusable items, and supporting sustainable businesses.

Agricultural runoff

Water pollution in Australia has many sources, from sewage treatment plants becoming blocked with materials flushed down the toilet by members of the public, to industrial waste and oil spills. However, agricultural runoff is a significant issue, especially for the Great Barrier Reef.

Nitrogen levels in Cattle Creek, for example, were three times above environmentally safe levels in 2018, and the creek was choked with sediment. Nearby Clairview Creek suffered the same fate after more rain, whereas photographs show that it used to remain clear after rainfall.

The average yearly inputs of nitrogen from the land have nearly doubled from 23,000 to 43,000 tonnes over the past 150 years, while phosphorus inputs have tripled from 2,400 tonnes to 7,100 tonnes. While most of this eventually gets flushed out to sea, transferred to the atmosphere, or buried in coastal sediments, net levels in reef waters may be slowly increasing.

The WWF has called for stronger laws to protect the reef from agricultural pollution, with a spokesperson saying that "the hundreds of millions invested in Reef water quality is being wasted without effective Reef pollution laws."

Industrial waste

Water pollution in Australia has been an issue for millennia, with early human settlements leading to localized water pollution. However, the Industrial Revolution marked a critical turning point in the history of water pollution, and the introduction of new technologies and large-scale coal use altered the nature and scale of human environmental impact. This period saw factories discharging untreated toxic waste into nearby rivers and other waterways, contaminating drinking water supplies and impacting human health.

The rapid growth of cities during the Industrial Revolution exacerbated the problem, as sewage treatment was often inadequate or non-existent, leading to further pollution of waterways. The scale of this pollution created lasting environmental damage that continues to impact Australia today, with many industrial sites from the 19th and 20th centuries still contaminated and posing health and environmental risks.

Untreated industrial wastewater carries excessive loads of nitrogen and phosphorus, which contribute to eutrophication, a harmful process that can kill a body of water. In addition, industrial waste contains carcinogens, such as dioxins and embalming fluids, which have been linked to various health issues, including heart disease, diabetes, and reproductive problems.

The widespread production and use of plastics have also created a new form of pollution, with plastic waste littering land and oceans, contributing to environmental degradation and harming wildlife. Microplastics, small fragments of plastic debris, are now pervasive in ecosystems, even being found in food and drinking water, highlighting the severity of this global environmental challenge.

Sewage treatment plants

Water pollution in Australia is caused by a variety of sources, including industrial waste, oil spills, plastic pollution, and sewage. While modern sewage treatment plants have improved the management of wastewater, the history of sewage treatment in Australia reveals a journey towards more efficient and sustainable practices.

One of the earliest mentions of sewage treatment in Australia dates back to the 1930s when lagoons were introduced to the Western Treatment Plant in Melbourne to treat sewage using land and grass filtration methods. This treatment plant has undergone significant upgrades over the years, including the installation of the first modern lagoon in 1986, which uses mechanical aerators to accelerate the natural sewage treatment process.

Sydney, another major Australian city, has also made substantial investments in its wastewater treatment infrastructure. By the Second World War, only half of Sydney's households were connected to the sewerage system, leading to extensive investments in the wastewater system during the second half of the 1900s. The Hawkesbury-Nepean catchment area in Sydney's west saw the construction and modification of numerous intensive treatment plants to address the issue of sewage discharge at Bondi, Malabar, and North Head, which resulted in poor beach water quality and environmental degradation.

In recent years, there has been a growing focus on improving environmental standards and reducing the impact of sewage treatment plants on the surrounding ecosystems. For instance, the Melbourne Sewerage Strategy set a 50-year vision to transform the sewerage system from mere "waste disposal" to a sustainable approach that recovers valuable resources. Similarly, Sydney Water has invested heavily in its wastewater treatment plants to reduce odours and enhance environmental outcomes, such as extracting biosolids fertiliser from the wastewater treatment process to improve soil conditions for local farmers.

While modern treatment plants are designed with backup systems to prevent major water pollution incidents, challenges still exist. For instance, treatment plants may struggle with certain types of waste that are flushed down household drains or toilets, such as feminine hygiene products, which can cause blockages in the system. Additionally, industries that are permitted to dispose of materials or chemicals into the sewerage system must do so under strict guidelines to minimise the risk of water pollution.

Oil spills

Water pollution in Australia, including oil spills, can be traced back to a variety of sources and causes. Oil spills, in particular, pose a significant threat to the country's marine environment and have multiple causes, ranging from accidental spills to intentional illegal discharges.

In Australia, the Australian Maritime Safety Authority (AMSA) is responsible for coordinating the cleanup of oil spills in coastal waters. They employ specialised equipment and techniques, such as aerial dispersant capabilities, to manage and remediate oil spills. Additionally, they work in cooperation with state and territory agencies, as well as industry stakeholders, to respond effectively to pollution incidents.

The discharge of oil by vessels at sea is a significant concern. The intentional and illegal release of bunker fuel oil and waste oils by ships is a major contributor to oil spills. These oils are often released into the sea, impacting the marine environment and the wildlife that inhabits it.

To address oil spills and water pollution, it is crucial to identify the responsible authority. This involves determining the source of the pollution, whether it be from households, industries, or maritime activities, and then taking appropriate action. Modern treatment plants play a crucial role in treating sewage to ensure it is safe to release back into the environment, and there is a growing trend of recycling sewage to further minimise environmental impact.

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