Emerging industries are changing the nature of trade waste. Aquamation is also known as alkaline hydrolysis or water cremation.
Aquamation is promoted as a lower-emissions alternative to traditional cremation because it uses water, heat and alkaline chemicals to break down human remains, leaving bone fragments and a liquid by-product. Some providers promote the process as using less energy than flame cremation and avoiding direct air emissions. However, for councils and utility providers, the key issue is not only whether aquamation has environmental benefits, it is whether the resulting liquid by-product can be safely and lawfully accepted into the sewerage network.
Trade waste management often has a focus largely on pH, grease, suspended solids and conventional industrial pollutants. Today, councils are increasingly expected to manage more complex waste streams, including emerging contaminants, pharmaceuticals, microplastics, industrial chemicals and high-strength organic loads.
Aquamation captures the broader challenge. A process may be marketed as “green”, but that does not mean it is low risk for sewerage infrastructure, treatment plant performance, biosolids, recycled water or environmental authority compliance.
Approvals matter
Under the Water Supply (Safety and Reliability) Act 2008 (Qld), a person must not discharge trade waste into a sewerage service provider’s infrastructure without approval. Before granting an approval, the provider must be satisfied that the proposed discharge is not a ‘prohibited substance’ and will not harm the sewerage system, endanger workers, or exceed the treatment plant’s capacity to treat the discharge to an acceptable standard. The provider must also consider the effect of the discharge on any existing or potential reuse of wastewater or sludge.
For new or unusual industries, the approval process should not be treated as a routine administrative step. It is the key mechanism for defining what is authorised, what limits apply, what pre-treatment is required and what monitoring must occur.
For aquamation and similar waste streams, councils and utility providers should be asking:
- What is the volume, strength, pH and temperature of the discharge?
- What chemicals or contaminants may be present?
- Is neutralisation or pre-treatment required before discharge?
- Could the discharge affect biological treatment processes?
- Could it affect biosolids, recycled water or effluent reuse?
- What sampling, reporting and record-keeping is needed?
- Who bears the cost if the discharge causes network or treatment plant impacts?
The operator remains exposed
Councils and utility providers are not only approval-makers. They are also operators of sewerage networks and sewage treatment plants.
The Environmental Protection Act 1994 imposes a General Environmental Duty requiring Council’s and utility providers to take all reasonable and practicable measures to prevent or minimise environmental harm. A duty to restore may also apply where contamination causes unlawful environmental harm.
This means that even where a trade waste customer generates the waste, the sewerage service provider may still face regulatory action if the discharge contributes to treatment failure, environmental authority non-compliance, contamination or an unlawful release.
The regulatory gap problem
A key difficulty with aquamation and other emerging industries is that existing trade waste approvals, trade waste plans and environmental authority conditions may not have been drafted with these waste streams in mind.
Environmental authority conditions may also be silent on emerging contaminants or changing industrial activities. That silence is not permission to ignore the risk. Sewerage service providers should regularly review their trade waste approval frameworks, monitoring programs and management plans to ensure they remain fit for purpose to protect the sewerage network and meet environmental standards.
If a provider does not understand a proposed discharge, it should require the information, technical assessment and approval conditions needed to manage that risk before accepting it into the network.
What councils and utilities should do now
Councils and utility providers should consider a trade waste program health check, particularly where new or unusual waste streams are emerging.
State guidance would assist consistency, but councils and utility providers still need local policies that reflect their own network capacity, treatment plant limits, environmental authority conditions and reuse pathways. Waiting for a State-wide position may leave providers exposed if a novel discharge causes infrastructure damage, treatment failure or environmental non-compliance.
Councils and utilities should:
- map high-risk customers and emerging industries;
- set clear local policy requirements for novel or high-risk discharges, particularly where State guidance is limited;
- modernise approval conditions;
- require pre-treatment, sampling and reporting;
- assess impacts on treatment plants, biosolids and recycled water;
- engage early with the State regulator where environmental authority compliance may be affected;
- preserve evidence of non-compliance;
- escalate enforcement where risks are not managed;
- recover costs from risk-generating customers; and
- document decisions and mitigation measures.
Key takeaways
Aquamation may have environmental advantages over traditional cremation, but councils should not assume that “green” means “low risk” for sewerage infrastructure.
For utility providers, the critical issue is whether the discharge can be accepted without harming the sewerage network, treatment plant performance, workers, biosolids, recycled water outcomes or environmental authority compliance.
Emerging industries require current, risk-based and enforceable trade waste approvals. Providers that review their approval frameworks early will be better placed to support innovation while protecting infrastructure, the environment and customers.