Unexpected taste and odour (T&O) in drinking water is an emerging issue for the Australian water industry as it undermines customers’ trust in drinking water suppliers. Most water utilities monitor only cyanobacterial and microalgal populations, and measure only geosmin and MIB concentrations in raw water, which is likely to overlook the full extent of biogenic T&O challenges in the supply of drinking water. Conventional coagulation/flocculation/filtration are often adopted for T&O removal. The project intends to identify key producers in source water and determine the treatability of unknown T&O for the proactive management of drinking water.

PhD Thesis underway by Jin Zhu.

The Australian water industry is currently focused on two VOCs, namely geosmin and MIB, which release an earthy-musty smell. Microorganisms that live in source water or within water distribution pipes are known to produce other unpleasant VOCs. This project intends to detect and quantify taste and odour (T&O) chemicals beyond geosmin and MIB in source water through chemical and sensory analysis. Project aims to identify and/or semi-quantify these unknown VOCs in source water and develop T&O wheel specific to NSW source water. The project also anticipates developing a risk indicator database for different T&O chemicals.

Thesis underway.

To face the mounting pressures of increasing demands on depleting fresh water supplies, the water industries are compelled to explore alternative water supplies such as desalination, water recycling (Indirect and Direct Potable Reuse), and storm water reuse, among others. However, community attitudes to such alternative sources and technologies remain a critical barrier to be overcome in most contexts.  This research will explore community attitudes to different sources of water, particularly in relation to trust (both in the relevant technology, and trust in the administrating water utility), the perceived need for alternatives in light of climate change, and the so-called ‘yuck factor’, which is often cited in the water literature as a key cause of negative attitudes to alternative water sources.

PhD Thesis underway by Christina Semasingha.

Cyanobacterial blooms are a concern for water utilities due to the potential production of cyanotoxins and taste and odours. Current detection methods are slow and may not capture changes in bloom density which can prevent utilities in rapidly adjusting their treatment process. This project investigated using in situ fluorometers as a tool for real-time cyanobacteria monitoring an treatment adjustment.

PhD Thesis completed by Florence Choo in 2019.

Detection of Algal and Cyanobacterial blooms have increased in lakes, rivers and reservoirs over the last two decades. This hampers drinking water treatment processes due to the high cell numbers and the release of algal organic matter that comprises toxins and taste and odour compounds. This project examined the in-depth potential of in situ fluorometers to improve early warning of bloom development via the analysis of fluorescent cell pigments to give an estimate of cell biovolume.

PhD Thesis completed by Sara Imran Khan in March 2019.

The presence of taste and odour (T&O) is a growing concern for the water industry due to negative associations with unsafe drinking water. Although consumers primarily judge water quality by its aesthetic properties, T&O compounds are usually present in trace concentrations. This project investigated current complaint management processes and evaluated analytical techniques for detecting T&O compounds.

Honours Thesis completed by Lily Liu in June 2015.

This project revised operational methodologies in all systems from catchment to tap providing an improved understanding of the resource and cost implications.  The research informed the development of future water plans providing improved aesthetic impact for customers.

Honours Thesis completed by Tara Callingham in August 2017.

This project will use granular activated carbon to remove algal metabolites. Adsorption and biodegradation of algal metabolites will be monitored and modelled in the laboratory and at pilot scales, with the aim of guaranteeing safe and cost-effective drinking water treatment.

The environmental conditions which cause blue-green algae (cyanobacteria) blooms vary according to location, the climate, and other attributes of aquatic ecosystems. This variety has made it difficult to develop one broadly applicable predictive model for cyanobacterial blooms. Water utilities monitor source waters to implement cyanobacterial risk management programmes but there are no standard protocols while limited information transfer between utilities has prevented the identification of management strategies that do or do not work. This research reviewed literature about early warning systems (Almuhtaram et al., 2021) and source control strategies, conducted a survey of 35 utilities in America and Canada (74%) and Australia (Kibuye et al., 2021) and evaluated selected control strategies. These different types of information were synthesised into decision trees within an overarching guidance document. It was concluded that a 3-tier framework to detect algal blooms which monitored biological activity, then confirmed the identification of cyanobacterial genes and associated metabolites gave sufficient early warning, while multi-barrier control strategies gave field-scale efficacy and enabled timely responses.

Blue-green algae (cyanobacteria) can bloom in marine and freshwater and cause additional problems for water utilities when they produce toxins and taste and odour compounds. This project consolidated a wealth of knowledge and experience in the management of cyanobacteria into an electronic / online international, practical, and user-friendly manual. It includes information about conducting risk assessments, developing monitoring programmes and incident management strategies, and management procedures to mitigate the risk posed by cyanotoxins.