How are organisations incorporating water security and reuse in water-stressed environments?

By applying a combined approach of technical, compliance and social solutions, organisations are responding to water stress by aligning with best practices, such as strategic investment and collaboration, policy alignment with UN Sustainable Development Goals and public engagement and education. Technical solutions point to water treatment technologies, decentralised and centralised systems, emerging technologies and monitoring and managing emerging contaminants.

Although each water-stressed environment and community may face specific threats, there are some common challenges:

• Public perception: Building trust in water reuse is critical. Organisations invest in public outreach and education, using positive terminology (like “pure water”) to improve acceptance, as seen in the United States and Australia.
• Technical barriers: Implementing advanced treatment technologies can be costly and complex, especially in regions with limited resources or technical expertise.
• Regulatory compliance: Monitoring for emerging contaminants (e.g., pharmaceuticals, PFAS) and meeting evolving regulations is a growing challenge.

Despite these challenges, organisations are investing in education and public outreach to engage communities and stakeholders and raise awareness about water’s finite nature. Investment in water reuse infrastructure is also critical yet it requires global dialogue, sharing of data and collaboration to accelerate implementation at scale.

Many organisations are also aligning their water security strategies with the UN’s Sustainable Development Goal 6, which targets water recycling, sustainable withdrawals and international cooperation. This allows efforts to be globally recognised and measurable.

These challenges, along with the context and resources available, are critical to determining a suitable solution for each water-stressed community.

Along with public outreach and heightened awareness about water’s importance, technical solutions are at the heart of disarming the threats to water resources. At GHD, we have identified four different approaches to solving the most common challenges water-stressed environments are facing today.

1. Advanced water treatment technologies

• Multi-barrier treatment trains: These combine ultrafiltration, reverse osmosis (RO), advanced oxidation processes (AOP) and chemical disinfection to achieve extremely high levels of pathogen and contaminant removal.
• Membrane bioreactors (MBR): Increasingly used for both indirect and direct potable reuse, MBRs offer efficient treatment and are being piloted in large-scale projects in Southern California.
• Carbon-based advanced treatment: In some regions, carbon-based processes (ozonation, biofiltration, GAC) are used where RO concentrate disposal is challenging, still achieving high pathogen and chemical control.

2. Decentralised and centralised systems

• While centralised systems dominate in many regions, there is growing interest in decentralised solutions, especially in Asia Pacific. These systems are tailored to local needs — often using smaller-scale versions of advanced treatment technologies — and require careful consideration of economics and stakeholder engagement.

3. Emerging technologies

• Organisations are exploring new technologies such as algal turf scrubbers, nano bubbles, zero liquid discharge (ZLD), thermal hydrolysis and AI-driven treatment optimisation. These innovations aim to improve efficiency, decentralise treatment and recover resources from waste streams.

4. Monitoring and managing emerging contaminants

• Facilities increasingly monitor for contaminants of emerging concern (CECs), pharmaceuticals and PFAS compounds. Advanced treatment steps and critical control point monitoring are used to maintain regulatory compliance and public safety.

What worked for others may not be a perfect fit for you, but it’s a valuable starting point for shaping your own approach. Blended approaches from experiences that have proven successful in regions such as Australia, California and Singapore combine robust policy frameworks, advanced technologies and strong public engagement.

Keep an open mind to applying both centralised and decentralised systems depending on context and invest in research and piloting new technologies to stay ahead of emerging challenges.