THE CHALLENGE:
Noosa Springs Golf Course identified water quality concerns in one of their 5,500m2 Golf course waterbodies. Laboratory analysis revealed elevated cyanobacteria levels that required intervention under National Health and Medical Research Council recreational water guidelines.
The water body receives treated effluent from a local WWTP. This treated water is then reused for irrigation across the golf course. While this approach supports sustainable water management, the nutrient-rich effluent can create conditions favourable to algal growth.
The 4m deep waterbody exhibited cyanobacterial contamination, with total cyanobacteria concentration of 96,410 cells per millilitre and biovolume of 22.85 cubic millimetres per litre. The potentially toxic species Dolichospermum circinale dominated at 89,300 cells per millilitre, comprising 93% of total cyanobacteria present.
Golf course waterbodies present unique management challenges. They must simultaneously serve aesthetic, irrigation, and ecological functions while remaining safe for patrons, staff, and neighbouring residents who interact with them daily. The course management sought a solution that would restore water quality and maintain the waterbody as a landscape asset.
OUR SOLUTION:
BioRemedy developed a combined mechanical and biological treatment strategy to address both the immediate bloom and the underlying conditions favouring cyanobacterial dominance.
Mechanical Treatment
Rio AG20 Circulator: Installed to address thermal stratification and promote water movement throughout the waterbody. The low-speed, twin-propeller system generates high flow rates while minimising disturbance to aquatic life, preventing stagnant zones and disrupting the stable surface conditions that allow cyanobacteria to outcompete other phytoplankton groups.
Force 7 Subsurface Aerator: Deployed to enhance dissolved oxygen levels throughout the 4m water column. Increased oxygen supports aerobic microbial activity, suppresses phosphorus release from sediments, and creates conditions less favourable to cyanobacterial growth.
Chemical Intervention
Agritec Algaecide: Applied during the first week of treatment (10 litres in two doses) to suppress the active bloom and reduce the immediate cyanobacterial load.
Biological Treatment
EcoShock Beneficial Bacteria: Weekly applications of seven sachets (each 250 grams) introduced bacterial populations that compete with cyanobacteria for available nutrients. By reducing the nitrogen and phosphorus pool, biological treatment helps prevent bloom recurrence following initial control measures.
This approach addressed both the existing contamination and the physical and biological conditions that had allowed the bloom to develop.
THE RESULTS:
Follow-up laboratory analysis after 8 weeks of treatment demonstrated a transformation in water quality.
Cyanobacteria Reduction
Total cyanobacteria fell from 96,410 to 3,840 cells per millilitre, a 96% reduction. The potentially toxic Dolichospermum circinale was reduced from 89,300 to just 410 cells per millilitre, a 99.5% reduction. Cyanobacteria biovolume dropped from 22.85 to 0.16 cubic millimetres per litre, a 99.3% reduction.
Alert Level Status
The waterbody’s classification improved to Green Alert under NHMRC recreational water guidelines, indicating it was now suitable for continued monitoring rather than requiring restrictions on use.
Ecological Rebalancing
Beyond cyanobacteria reduction, the phytoplankton community showed signs of healthy ecological recovery. Diatom populations increased from 4,760 to 27,170 cells per millilitre a 471% increase. Green algae rose from 1,920 to 8,520 cells per millilitre a 344% increase. Both groups showed increased species diversity.
This shift from cyanobacterial dominance toward a more diverse algal community indicates the treatment approach addressed underlying conditions rather than simply eliminating all algae indiscriminately.
WHY THIS MATTERS:
This project demonstrates the effectiveness of combining mechanical and biological treatment approaches for remediating cyanobacterial contamination in recreational water settings. The successful intervention offers several key insights for golf course managers and water quality professionals.
- Water quality was restored to Green Alert status within eight weeks, a timeframe measured in weeks rather than months or years.
- The 99.5% reduction in the potentially toxic Dolichospermum circinale significantly improved the safety profile of a waterbody used daily by patrons, staff, and neighbouring residents.
- Rather than simply killing all algae, the treatment approach promoted a shift toward a diverse phytoplankton community dominated by non-harmful diatoms and green algae.
- Initial algaecide application was followed by ongoing biological treatment, reducing reliance on repeated chemical applications.
- Mechanical circulation and aeration modified the physical conditions that favour cyanobacterial growth, providing ongoing suppression rather than temporary symptom relief.
- The successful treatment of a waterbody fed by treated effluent demonstrates that combined mechanical and biological approaches can manage water quality even when nutrient inputs are ongoing. This is particularly relevant for golf courses and facilities using reclaimed water for irrigation.
For managers of Class B recreational waters across Australia, including ornamental lakes, irrigation storages, constructed wetlands, and facilities using treated effluent systems, this project offers a proven template for restoring waterbodies affected by harmful algal blooms.
ABOUT THE TECHNOLOGY:
Rio AG20 Circulator
The Rio AG series is designed for waterbodies up to 10,000 square metres. The low-speed, twin-propeller gearbox system generates high flow rates while minimising disturbance to aquatic life. By mixing the water column, the circulator breaks down thermal stratification, distributes oxygen and nutrients evenly, and eliminates the stable surface conditions that allow buoyancy-regulating cyanobacteria to maintain optimal positioning for light capture.
Force 7 Subsurface Aerator
The Force 7 is an aeration and mixing system designed for high-capacity water treatment applications. It delivers oxygen transfer through subsurface injection, increasing dissolved oxygen levels throughout the water column. Elevated oxygen supports aerobic microbial processes and suppresses the release of phosphorus from sediments that occurs under anoxic conditions, a significant internal nutrient source that can sustain cyanobacterial blooms even when external inputs are controlled.
Agritec Algaecide
Agritec is formulated to control and eliminate algae in aquatic environments including ponds, lakes, and reservoirs. It is designed to be safe for use in settings where water quality is important for plant and animal health, providing rapid knockdown of existing bloom populations.
EcoShock Beneficial Bacteria
EcoShock sachets contain a high concentration of bacteria designed to oxygenate water, neutralise harmful acids, and promote aerobic digestion of organic waste. The bacteria compete with cyanobacteria for available nutrients, reducing the pool of nitrogen and phosphorus available to support future bloom development.
IMPLEMENTATION APPROACH:
The treatment was implemented in a staged sequence to maximise effectiveness.
The BioRemedy project team conducted initial site assessment in September 2025. Visual inspection revealed characteristics consistent with cyanobacterial bloom conditions, and water samples were submitted to Ecoscope Environmental Laboratory for NATA-accredited phytoplankton analysis. Laboratory results confirmed elevated cyanobacteria levels, with the potentially toxic Dolichospermum circinale dominating the cyanobacterial population. This baseline data informed the treatment strategy development.
The Rio AG20 circulator and Force 7 aerator were then installed to provide continuous circulation and aeration of the four-metre water column. During the first week, Agritec algaecide was applied in two doses totalling 10 litres to suppress the active bloom and reduce the immediate cyanobacterial load.
Following initial bloom suppression, weekly applications of EcoShock beneficial bacteria commenced, with seven sachets at 250 grams each applied throughout the monitoring period. Follow-up sampling was conducted in November 2025, with laboratory analysis confirming the improvement to Green Alert status.
This systematic approach ensured mechanical treatment addressed underlying conditions while chemical and biological components targeted existing contamination and ongoing nutrient availability.
PROJECT TEAM:
The success of this project reflects the expertise and collaboration of:
BioRemedy Project Team: Conducted site assessments, equipment installation, and ongoing treatment applications throughout this project. Their practical expertise and commitment to achieving water quality improvements were essential to the successful outcomes documented in this study.
Ecoscope Environmental Laboratory: Provided NATA-accredited phytoplankton identification, enumeration, and biovolume analysis services under the direction of Howard Howell, Principal Biologist. The laboratory’s rigorous analytical work provided the quantitative foundation for assessing treatment effectiveness.
Greenshed/Living Turf: Supplied the Rio AG20 circulator and Force 7 aerator for this installation, providing essential equipment and support for the mechanical treatment components.
Noosa Springs Golf Course: Their willingness to participate in this case study and support for water quality monitoring activities enabled the documentation of outcomes that may benefit other recreational water managers facing similar challenges.
For golf course managers and water quality professionals facing cyanobacterial challenges in recreational waterbodies, this project offers a proven pathway for rapid remediation. The combination of mechanical circulation, aeration, and biological treatment can restore water quality within weeks, protecting patrons, staff, and neighbouring communities while preserving the aesthetic and functional value of these important landscape assets.
Contact our team today to learn how a combined treatment approach might benefit your water management challenges.