Howard Fallowfield

Flinders University · College of Science and Engineering

Over the last 20 years, there has been a growing requirement by governments around the world for organisations to adopt more sustainable practices. Wastewater treatment is no exception, with many currently used systems requiring large capital investment, land area and power consumption. High rate algal ponds offer a sustainable, efficient and lower...

Despite the many recognised benefits, the application of high rate algal ponds (HRAP) to manage wastewater treatment in small communities has been limited. To be incorporated into the South Australian Community Wastewater Management Scheme (CWMS), new wastewater treatment systems are required to undergo validation and obtain regulatory approval fro...

A high rate algal pond (HRAP) incorporated into a community wastewater management scheme was operated over two years in the Mediterranean climate of Kingston on Murray, South Australia. Uniquely, the study evaluated the performance of the HRAP when fed (12 m³ day⁻¹) either treated effluent from on-site septic tanks or a facultative pond further tre...

Microalgae grown in high rate algal ponds (HRAP) treating wastewater are considered a promising feed for biofuel production. Biomass productivity is often considered to be limited by carbon availability, with the addition of CO2 being the proposed solution. Biogas from anaerobic wastewater treatment potentially provides a cheap, co-located CO2 sour...

Wastewater-based epidemiology (WBE) is a surveillance approach used to examine chemical and biological targets within a population. Historically, the most common approaches to wastewater sampling include grab sampling and composite sampling, which can be performed manually or using an automated sampler. However, there are inherent flaws with these...

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) have been identified as emerging contaminants of public health concern. With PFAS now detected globally in a wide range of environments, there is an urgent need for effective remedial treatment solutions at the field scale. Phytoremediation presents a potential remediation strategy for PFAS that...

Constructed wetlands (CW) are implemented to improve water quality through filtration by plants (macrophytes), which sequester nutrients and contaminants. Macrophyte beds in CWs reduce the speed of water flow, aiming to improve the water quality by sedimentation and filtration with increasing distance from the inflow. Few studies have assessed spat...

High rate algal ponds (HRAPs) used for wastewater treatment typically are mixed continuously. This increases capital and operating costs, particularly for remote communities considering utilising solar power with battery storage....

High rate algal ponds (HRAP) are considered a promising system for coupling wastewater treatment with the growth of microalgae biomass. However, the absence of a cost-effective harvesting method limits this application. In this study, in situ autoflocculation, via magnesium hydroxide precipitation, was assessed in a HRAP containing 33 m³ of HRAP tr...

Worldwide, foodborne illness is a significant public health issue in both developed and developing countries. Salmonellosis, campylobacteriosis and shigellosis are common foodborne gastrointestinal illnesses caused by the bacteria Salmonella spp., Campylobacter spp. and Shigella spp. respectively. These zoonotic diseases are frequently linked to eg...

There is a paucity of information regarding the interaction between GONPs and natural aquifer sediments. Therefore, batch and column experiments were carried out to determine the transport, retention and attachment behavior of GONPs with the surfaces of native aquifer sediments. The experiments were performed with sediments comprising contrasting m...

https://futurewater.partica.online/future-water/future-water-2020/flipbook/59/ Future Water Magazine 2020

High rate algal ponds (HRAP's) are shallow, mixed systems for wastewater treatment, which use sunlight exposure for disinfection. Little is known regarding the relationships between the bacteria and viruses within HRAP systems. Uniquely, flow cytometry permitted the rapid identification of bacterial and viral populations in wastewater samples, sepa...

This research was conducted to evaluate the effect of co-transport of different-sized microorganisms on graphene oxide nanoparticles (GONPs) transport and retention in saturated pristine and biofilm-conditioned limestone columns. The transport and retention behavior of GONPs was studied in columns in the presence of MS2 -as a nano-sized- and Escher...

In recent years, treated wastewater has been widely used in managed aquifer recharge sites (MAR) for compensation of groundwater shortage in arid and semi-arid areas. However, the presence of suspended solids, microorganisms and pathogenic agents has led to different problems such as aquifer clogging and groundwater contamination. In this study, th...

Background Virus, as nano-sized microorganisms are prevalent in aquifers, which threaten groundwater quality and human health wellbeing. Virus inactivation by attachment onto the limestone surfaces is a determining factor in the transport and retention behavior of virus in carbonaceous aquifers. Methods In the present study, the inactivation of MS...

Eggs are a highly nutritious food source used in a wide range of food products. In Australia, eggs are a frequent source of foodborne salmonellosis outbreaks, associated with eggshell contamination with Salmonella enterica serovar Typhimurium (ST). Despite their potentially hazardous nature, raw eggs are often used and consumed in mayonnaise, mouss...

Raw egg products are often associated with salmonellosis. The Australian guidelines recommend raw egg mayonnaise to be prepared and stored under 5 °C and adjusted to a pH less than 4.6 or 4.2. Despite these guidelines, a significant amount of salmonellosis outbreaks are recorded annually in Australia. The aim of this study was to investigate the ef...

Nitrifying trickling filters (NTFs) are often introduced to pre-treat waters before chlorination process, to reduce the ammonia-driven chlorine consumption in wastewater treatment. As a passive aerated system, the only power needed is to transport the water to the top of the filter for distribution. Thus, understanding the role of filter aspect rat...

http://apri.com.au/wp-content/uploads/2020/08/4A-110-Final-Report.pdf

Natural ultraviolet irradiance disinfection is known to play a significant role in both natural wastewater treatment systems and drinking water disinfection processes, while the influence of ultraviolet B (UVB) delivering method on sunlight disinfection outcome is still unclear. This study aims to determine the effects of environmentally relevant t...

http://porkcrc.com.au/wp-content/uploads/2019/01/4A-105-AEROBIC-AND-ALGAL-31Jan19.pdf

Abstract Salmonellosis is a foodborne illness of public health significance. In Australia the incidence of salmonellosis has been significantly increasing over the last decade with eggs and raw egg products identified as the main source of outbreaks. The primary cause of salmonellosis in Australia is S. typhimurium. This study investigated the effe...

Attenuation of sunlight in wastewater treatment ponds reduces the depth of the water exposed to disinfecting irradiances. Shallow pond depth with paddlewheel rotation increases exposure of pathogens to sunlight in high rate algal ponds. Generation of thin films, using pond walls as inclined planes, may increase inactivation of pathogens by increasi...

In Australia the incidence of salmonellosis is increasing with Salmonella Typhimurium linked to eggs and raw egg products identified as the main cause. Australian guidelines recommend raw egg mayonnaise is prepared and stored under 5 0 C and adjusted to a pH of 4.6. This study investigated the combined effect of pH and temperature on the survival o...

South Australian community wastewater management schemes (CWMS) treat wastewater using waste stabilisation ponds before disposal or reuse. This study compared the performance of a facultative pond, 6,300 m2, 27.5 d theoretical hydraulic retention time (THRT), with a high rate algal pond (HRAP) operated at depths of 0.32, 0.43 and 0.55 m with THRT e...

The objective of this review is to highlight the need for further investigation of microbial toxicity caused by desorption of surfactant from Surfactant Modified Zeolite (SMZ). SMZ is a low cost, versatile permeable reactive media which has the potential to treat multiple classes of contaminants. With this combination of characteristics, SMZ has si...

Surfactant Modified Zeolite (SMZ) represents a versatile, cost-effective permeable reactive material, capable of treating multiple classes of contaminants. The potential for HDTMA-Br, a cationic surfactant commonly used to modify zeolite, to desorb from the zeolite surface has been identified as a potential issue for the ongoing use of SMZ in water...

The cultivation of microalgae within municipal and agricultural wastewater offers the opportunity to treat the water and partition nutrients into valuable biomass. Harvesting of those algae is a challenge, as conventional coagulants (iron and aluminum salts) contaminate algae and lock up phosphorus preventing beneficial reuse. We show that floccula...

Eggs have a high nutritional value and are an important ingredient in many food products. Worldwide foodborne illnesses, such as salmonellosis linked to the consumption of eggs and raw egg products, are a major public health concern. This review focuses on previous studies that have investigated the procedures for the production of microbiologicall...

http://www.publish.csiro.au/an/pdf/ANv57n12abs

Salmonellosis is one of the main causes of foodborne illnesses worldwide, with outbreaks predominately linked to contamination of eggs and raw egg products, such as mayonnaise. This review explores previous studies that have investigated Salmonella control mechanisms utilized in the production of raw egg mayonnaise and other food products. Apart fr...

This study investigated the volume of wastewater retained on the surface of three different varieties of lettuce, Iceberg, Cos, and Oak leaf, following submersion in wastewater of different microbial qualities (10, 10², 10³, and 10⁴ E. coli MPN/100 mL) as a surrogate method for estimation of contamination of spray-irrigated lettuce. Uniquely, Esche...

Presentation describing the adoption of high rate algal ponds as an alternative wastewater treatment system for communities in rural South Australia

Foodborne salmonellosis is a major public health concern, with contaminated eggs identified as a significant source of infection. In Australia, the most prevalent cause of salmonellosis from eggs is Salmonella enterica subsp. enterica serovar Typhimurium. This study explored the effect of temperature after 1, 7, 14, 21, and 28 days of storage on co...

This study assessed the contamination of Escherichia coli, in lettuce grown with treated domestic wastewater in four different irrigation configurations: open spray, spray under plastic sheet cover, open drip and drip under plastic sheet cover. Samples of lettuce from each irrigation configuration and irrigating wastewater were collected during the...

Aims: High rate algal ponds (HRAPs) have been suggested as replacements for waste stabilisation ponds (WSPs) in Community Wastewater Management Systems (CWMS) used in rural South Australian (SA) towns. Treated effluent from CWMS is reused for irrigation. To manage the risk of human exposure to pathogens, the disinfection performance of HRAPs was v...

Pathogen removal in wastewater treatment ponds is limited by poor light penetration in the water column. Solar exposure is increased in high rate algal ponds through paddlewheel mixing and shallow pond depths however; insufficiently exposed areas remain. To address this inclusion of an inclined plane to these treatment ponds was considered to incre...

The nitrifying trickling filter (NTF) is a process commonly used in wastewater treatment to remove ammonia. What is less clear is its ability to remove emerging organic contaminants. This study evaluated the potential of NTF to remove eight trace organic chemicals of concern (CoCs), with initial concentration of caffeine, bisphenol A, benzotriazole...

Oral presentation in Australasian Pig Science Association Inc (APSA)

Animal Production Science, 55, 11-12, pp1347-1575 http://www.publish.csiro.au/an/anv55n12ab092

Oral presentation in 2nd Annual RHD Conference, School of the Environment, Flinders University

Oral presentation in Water Research Australia SA Node Meeting https://www.waterra.com.au/publications/document-search/?download=1176

Water reuse has become increasingly important for sustainable water management. Currently, its application is primarily constrained by the potential health risks. Presently there is limited knowledge regarding the presence and fate of opportunistic pathogens along reuse water distribution pipelines. In this study opportunistic human pathogens Legio...

The authors wish to add the following amendments and corrections to their paper published in IJERPH [1].[...].

Legionella is an opportunistic pathogen of public health concern. Current regulatory and management guidelines for the control of this organism are informed by risk assessments. However, there are many unanswered questions and uncertainties regarding Legionella epidemiology, strain infectivity, infectious dose, and detection methods. This review fo...

A novel heterotrophic-autotrophic denitrification (HAD) approach supported by granulated spongy iron, pine bark and mixed bacteria was proposed for remediation of nitrate contaminated groundwater in an aerobic environment. The HAD involves biological deoxygenation, chemical reduction (CR) of nitrate and dissolved oxygen (DO), heterotrophic denitrif...

Although our previous studies indicated the two heterotrophic-autotrophic denitrification permeable reactive barriers (HAD PRBs) contained heterotrophic and autotrophic denitrifying bacteria and aerobic heterotrophs, convincing molecular and biochemical evidence for their existence is lacking and the bacterial communities remain largely unknown. Us...

Two potential heterotrophic-autotrophic denitrification permeable reactive barriers (HAD PRBs) were evaluated to remediate groundwater in situ. The first HAD PRB (Column 1) was packed with a mixture of spongy iron, pine bark and sand between 5 and 145 cm from bottom. The second HAD PRB (Column 2) was filled with a spongy iron and sand mixture layer...

Inhalation of potable water presents a potential route of exposure to opportunistic pathogens and hence warrants significant public health concern. This study used qPCR to detect opportunistic pathogens Legionella spp., L. pneumophila and MAC at multiple points along two potable water distribution pipelines. One used chlorine disinfection and the o...

High concentration of nitrate in drinking water is thought to be related to methemoglobinemia, cancers and even death. Due to the increasing anthropogenic activities, nitrate in groundwater is increasing in many areas of the world. Nitrate contamination is caused by nitrogenous fertilizers, livestock manures, agricultural irrigation, etc. This stud...

A novel heterotrophic-autotrophic denitrification (HAD) approach supported by mixing granulated spongy iron, methanol, and mixed bacteria was proposed for the remediation of nitrate-nitrogen (NO3-N) contaminated groundwater in a dissolved oxygen (DO)-rich environment. The HAD process involves biological deoxygenation, chemical reduction (CR) of NO3...

: Microbiologically influenced corrosion (MIC) is a mechanism increasingly being implicated in the corrosion of metals. Biofilms were detected in both copper and galvanised steel pipe and organisms which enhance corrosion or protect metal from corrosion were isolated. Representatives of 16 genera of microorganisms were isolated from copper and galv...

This study examined the composition and structure of nitrifying biofilms sampled from a high-rate nitrifying trickling filter which was designed to pre-treat raw surface water for potable supply. The filter was operated under a range of feed water ammonia and organic carbon concentrations that mimicked the raw water quality of poorly protected catc...

Waste stabilization ponds are an effective and inexpensive method for treating wastewater for re-use in agricultural and industrial processes. Carbon in the environment in recent years has become of increasing concern due to the threat of global climate change. The potential for algal–bacterial wastewater treatment systems to recycle carbon via pho...

The potential use of yellow velvetleaf (Limnocharis flava (L.) Buch) for remediation of lead (Pb) polluted water was studied in Green house experiment. The study was also investigated the distribution of lead in plant tissue. Plants of equal size was grown hydroponically and exposed to 0, 1, 5, 10 mgL -1 of Pb concentration for 10 days, 20 days, an...

The specific nature of fluid dynamics within waste stabilisation ponds can have a determining influence on their functional treatment performance. This paper presents the results of hydraulic tracer experiments undertaken to characterise the hydrodynamic behaviour of several pilot-scale advanced pond treatment systems (a duckweed-based pond, a conv...

To investigate the role of heterotrophic bacteria in the corrosion of galvanized steel in the presence of water. Samples were taken from corroding galvanized steel pipes conveying water for specialist applications, and heterotrophic bacteria were isolated and cultured. The majority of bacteria were Gram-negative aerobes and included Pseudomonas sp....

The interference of ammonia with the chlorination process is a problem for many reclaimed water treatment plant operators. This paper presents the findings from a series of pilot experiments that investigated the efficacy of high flow rate nitrifying trickling filters (NTFs) for the removal of low concentrations of ammonia (0.5-3.0 mg N L(-1)) from...

The application of nitrifying trickling filters (NTFs) to potable water treatment is less well understood than their application to wastewater treatment, particularly regarding the effect of low ammonia substrate concentrations and organic carbon loading on filter performance. A large pilot-scale NTF was operated under conditions that simulated the...

This study compared the nitrification potential of two separate Waste Stabilisation Ponds (WSPs) operating under differing physical and chemical conditions. In order to probe the nitrification potential of each system, the oxidation of ammonium and also the intermediate product nitrite was assessed using both in situ and laboratory micro-scale incu...

Waste stabilisation ponds (WSP) are efficient, cost-effective methods of treating wastewater in rural and remote communities in Australia. It is recognised that sunlight plays a significant role in their disinfection, however, due to the poor penetration of light in turbid waters it has been hypothesised that other mechanisms may also contribute to...

Instances of accelerated corrosion of galvanized pipe conveying water through specialist systems have been reported in the literature. The nature and speed at which corrosion has occurred suggests that microbially influenced corrosion (MIC) may be one of the causes. Bacteria were isolated from a previously failed pipe and assessed for their influen...