A look at the green alternatives that might just revolutionise water treatment. 

The water treatment industry has long had an uncomfortable truth: many of our most effective methods for controlling Legionella rely on chemical treatments that, while keeping people safe, aren’t exactly winning environmental awards. It’s the classic safety versus sustainability dilemma. 

At HCS Water Treatment, part of Premier Technical Services Group Ltd (PTSG), we’re increasingly hearing from clients who want both, effective Legionella control that doesn’t come with an environmental cost. The good news? Green water treatment isn’t just a pipe dream anymore. Innovative approaches are emerging that promise to protect both people and planet. 

The Chemical Conundrum 

Before we explore the alternatives, let’s acknowledge why chemical treatments became the industry standard in the first place: 

• They’re highly effective at killing bacteria 

• They provide residual protection throughout water systems 

• They’re well-understood, with decades of performance data 

• They’re generally cost-effective 

• They’re explicitly recognised in regulatory frameworks 

Traditional biocides like chlorine, chlorine dioxide, and various proprietary formulations have been the backbone of Legionella control for decades. They work, and in an industry where failure can mean fatal disease outbreaks, “it works” has understandably been the primary consideration. 

But this effectiveness comes with environmental baggage: 

• Chemical manufacturing processes with substantial carbon footprints 

• Potential for harmful disinfection by-products 

• Discharge of treated water into the environment 

• Impact on beneficial microorganisms in natural water systems 

• Chemical transportation and handling risks 

As one of our clients, a major hospitality provider, put it: “We’re spending enormous resources reducing single-use plastics and installing energy-efficient systems, yet we’re still putting chemicals down our drains every day. It feels inconsistent with our sustainability goals.” 

The Green Revolution: Alternative Approaches 

The good news is that the water treatment industry is in the midst of a green revolution, with several promising approaches emerging: 

1. Physical Water Treatment Systems 

Physical treatment methods use non-chemical mechanisms to control bacterial growth: 

Ultraviolet (UV) Disinfection 

UV systems use specific wavelengths of light to disrupt bacteria’s DNA, preventing reproduction: 

Advantages: 

• No chemicals required 

• No harmful by-products 

• Effective against a wide range of microorganisms 

• Low maintenance requirements 

Limitations: 

• No residual protection downstream 

• Requires clear water for effective penetration 

• Less effective against established biofilms 

• Energy consumption considerations 

Filtration Technologies 

Advanced filtration systems physically remove bacteria and their nutrients: 

Advantages: 

• Chemical-free operation 

• Can remove multiple contaminants simultaneously 

• No disinfection by-products 

• Can be combined with other treatment methods 

Limitations: 

• Regular replacement or cleaning required 

• Potential for bacterial growth on filter media 

• Pressure drop considerations 

• Not all filtration is fine enough to capture bacteria directly 

2. Temperature Optimisation 

Perhaps the original “green” control method, proper temperature management remains one of the most environmentally friendly approaches: 

Advantages: 

• No chemicals required 

• Highly effective when properly maintained 

• Aligns with energy efficiency when well-designed 

• Well-established in regulatory frameworks 

Limitations: 

• Energy considerations for maintaining temperatures 

• May require system modifications for effectiveness 

• Scalding risk management needed 

• Relies on consistent implementation 

3. Copper-Silver Ionisation 

While technically introducing substances into water, copper-silver ionisation uses natural elements rather than synthetic chemicals: 

Advantages: 

• Minimal environmental impact 

• Long-lasting residual effect 

• Effective against biofilm 

• Reduced chemical handling and storage 

Limitations: 

• Initial equipment investment 

• Requires monitoring of ion concentrations 

• Potential for staining in certain water chemistry 

• Metal discharge considerations 

4. Hydrodynamic Cavitation 

This emerging technology uses physical forces to disrupt bacterial cells: 

Advantages: 

• Chemical-free operation 

• Low energy consumption 

• No disinfection by-products 

• Minimal maintenance requirements 

Limitations: 

• Less established performance history 

• May require complementary treatments 

• System design considerations 

• Limited regulatory recognition 

5. Photocatalytic Oxidation 

This innovative approach uses light-activated catalysts to generate disinfecting agents from within the water itself: 

Advantages: 

• Minimal chemical additions 

• Effective against biofilms 

• Reduced environmental impact 

• Multiple treatment mechanisms 

Limitations: 

• Relatively new technology 

• Specific design requirements 

• Variable effectiveness in different water conditions 

• Initial cost considerations 

The Hydrosphere Solution: Leading the Green Revolution 

At HCS Water Treatment, we’re particularly excited about our Hydrosphere Dramatic Cleaning service, a standout eco-friendly solution that’s already delivering impressive results. 

This innovative cleaning method offers several key environmental benefits: 

• Zero chemicals used in the cleaning process 

• No wastewater discharged to drains during the procedure 

• Extended system lifecycle, reducing resource consumption 

• Minimised disruption, eliminating the need for system shutdown 

This eco-friendly approach aligns perfectly with our ARMOR service suite, designed to revolutionise water treatment where cooling efficiency is critical and environmental considerations are increasingly important. 

Real-World Success: Green Control in Action 

The transition to greener Legionella control isn’t theoretical it’s happening right now across the UK with clients we work with every day: 

Case Study: Healthcare Facilities 

Glasgow Royal Infirmary faced the complex challenge of maintaining water safety for vulnerable patients while minimising environmental impact. Working collaboratively, we implemented a solution that: 

• Utilised the latest smart technology to assess TMVs within the site 

• Created a digital asset list and condition report 

• Delivered compliant service without unnecessary disruption to vulnerable patients 

• Reduced chemical usage through optimised system design 

Our engineers were able to verify and diagnose fault conditions from readings of tests conducted, completing all certificates and record sheets while causing minimal disruption to ward or clinic protocols. 

Case Study: Hospitality Sector 

Across Whitbred’s portfolio of 1320+ buildings including hotels, bars and restaurants, we faced varied and fluid levels of occupation requiring a flexible approach. Our solution involved: 

• Collaborating to formulate a robust water risk assessment project plan and programme 

• Completing all required site risk assessments and remedial works 

• Implementing more sustainable treatment options where feasible 

• Maintaining compliance while reducing environmental impact 

By understanding the unique needs of the hospitality sector, including the varied occupancy patterns, we were able to develop solutions that maintained safety while progressively reducing chemical dependency. 

The Hybrid Approach: Pragmatic Sustainability 

While completely chemical-free systems are increasingly viable, many organisations benefit from a hybrid approach, drastically reducing chemical usage while maintaining robust protection: 

• Targeted application of chemicals only where alternatives aren’t viable 

• Lower concentration treatments supported by complementary methods 

• Green chemistry approaches using less harmful formulations 

• Optimised dosing through smart monitoring to minimise usage 

This balanced approach has proven particularly effective in complex environments like The Glasgow Academy, where our team collaborated to formulate a robust water management plan while being mindful of the presence of young pupils and the need for minimum disruption to daily operations. 

Making the Transition: Practical Steps 

Ready to green your Legionella control programme? Here’s how to begin the journey: 

1. Conduct an Environmental Impact Assessment 

Start by understanding your current environmental footprint: 

• Quantify chemical usage in your water systems 

• Identify high-impact areas for priority action 

• Establish baseline metrics for measuring improvement 

• Consider both direct and indirect environmental impacts 

2. Explore System Optimisation First 

Before investing in new technologies, optimise your existing systems: 

• Address hydraulic issues that might necessitate chemical treatment 

• Improve temperature control to reduce reliance on biocides 

• Eliminate redundant pipework that creates treatment challenges 

• Implement water efficiency measures that naturally reduce risks 

3. Consider a Phased Approach 

Transitioning to greener methods doesn’t have to happen overnight: 

• Begin with pilot programmes in defined areas 

• Demonstrate success before wider implementation 

• Gradually reduce chemical dependency as alternatives prove effective 

• Combine approaches to create robust, multi-barrier systems 

4. Focus on Outcomes, Not Methods 

Remember that the goal is safe water, not any old treatment approach: 

• Monitor results rigorously during transition periods 

• Be prepared to adjust strategies based on performance data 

• Maintain compliance as the non-negotiable priority 

• Document your approach for regulatory transparency 

The Future Is Green (And Safe) 

The water treatment industry is at an exciting crossroads. For decades, we’ve relied on chemical approaches because they were the best tools available. Today, technological innovations are creating new possibilities that don’t force us to choose between safety and sustainability. 

At HCS Water Treatment, our formula for water safety success has always included innovation and today that means embracing green technologies that deliver both compliance and environmental responsibility. 

The evidence increasingly shows that eco-friendly Legionella control isn’t just possible in many cases, it’s actually more effective than traditional approaches. By addressing the root causes of bacterial growth rather than simply applying chemical solutions, these methods often deliver more sustainable results in every sense of the word. 

As we found when working with the City of Edinburgh Council across their 418 properties, introducing more sustainable approaches alongside our ZetaSafe legionella risk assessments not only improved productivity but also reduced environmental impact significantly. 

Ready to explore how your organisation can transition to more environmentally responsible water treatment without compromising on safety? Contact HCS Water Treatment today on 0141 212 7247 or email us at hello@hcsuk.org to discuss how our specialist team can help you develop a water safety strategy that protects both people and planet. The green revolution in Legionella control is here and it’s safer than ever.