scholarly journals Development of a process-based model to predict pathogen budgets for the Sydney drinking water catchment

2007 ◽  
Vol 5 (2) ◽  
pp. 187-208 ◽  
Author(s):  
Christobel M. Ferguson ◽  
Barry F. W. Croke ◽  
Peter J. Beatson ◽  
Nicholas J. Ashbolt ◽  
Daniel A. Deere
Keyword(s):  
Drinking Water ◽  
Sewage Treatment ◽  
Point Sources ◽  
Control Measures ◽  
Specific Information ◽  
Management Options ◽  
Weather Events ◽  
Excretion Rates ◽  
Source Water Quality ◽  
Water Catchments

In drinking water catchments, reduction of pathogen loads delivered to reservoirs is an important priority for the management of raw source water quality. To assist with the evaluation of management options, a process-based mathematical model (pathogen catchment budgets - PCB) is developed to predict Cryptosporidium, Giardia and E. coli loads generated within and exported from drinking water catchments. The model quantifies the key processes affecting the generation and transport of microorganisms from humans and animals using land use and flow data, and catchment specific information including point sources such as sewage treatment plants and on-site systems. The resultant pathogen catchment budgets (PCB) can be used to prioritize the implementation of control measures for the reduction of pathogen risks to drinking water. The model is applied in the Wingecarribee catchment and used to rank those sub-catchments that would contribute the highest pathogen loads in dry weather, and in intermediate and large wet weather events. A sensitivity analysis of the model identifies that pathogen excretion rates from animals and humans, and manure mobilization rates are significant factors determining the output of the model and thus warrant further investigation.

A deterministic model to quantify pathogen loads in drinking water catchments: pathogen budget for the Wingecarribee

2005 ◽  
Vol 52 (8) ◽  
pp. 191-197 ◽  
Author(s):  
C.M. Ferguson ◽  
B. Croke ◽  
N.J. Ashbolt ◽  
D.A. Deere
Keyword(s):  
Drinking Water ◽  
Deterministic Model ◽  
Fate And Transport ◽  
Management Options ◽  
Water Utility ◽  
Relative Significance ◽  
E Coli ◽  
Utility Managers ◽  
Different Sources ◽  
Water Catchments

This paper describes the development and testing of a mathematical model as a tool to quantify pathogen loads in Sydney's drinking water catchments. It has been used to identify, quantify and prioritise sources of Cryptosporidium, Giardia and E. coli in the Wingecarribee catchment. The pathogen model promotes understanding of the relative significance of different sources of pathogen risks as well as their fate and transport as they move through the subcatchments. This pathogen model not only enables water utility managers to identify those catchment segments that may contribute the highest load of pathogens, but also where management options will be most effective.

Centralised versus decentralised sewage systems: a comparison of pathogen and nutrient loads released into Sydney's drinking water catchments

2004 ◽  
Vol 48 (11-12) ◽  
pp. 53-60 ◽  
Author(s):  
K. Charles ◽  
N. Ashbolt ◽  
C. Ferguson ◽  
D. Roser ◽  
R. McGuinness ◽  
...  
Keyword(s):  
Drinking Water ◽  
Sewage Treatment ◽  
Enteric Viruses ◽  
Nutrient Loads ◽  
Case Scenario ◽  
Nitrogen And Phosphorus ◽  
Worst Case ◽  
Catchment Population ◽  
Decentralised Systems ◽  
Water Catchments

Data collected from centralised and decentralised sewage treatment plants throughout Sydney's drinking water catchments was used to calculate the relative catchment loads of Cryptosporidium, enteric viruses, nitrogen and phosphorus for an initial screening assessment. Loads were assessed at median and 90 percentile values for expected and worst-cases scenarios. The expected scenario in the Sydney drinking water catchments is that decentralised systems (servicing 32,800 people) provide similar total loads to centralised systems (serving 70% of the catchment population) for total phosphorus (37,090 kg.y-1), Cryptosporidium (1011 oocysts.y-1) and enteric viruses (9.1 × 1013 y-1), but higher loads of total nitrogen (237,610 vs. 136,740 kg.y-1). Decentralised systems, however, were predicted to have higher loads in the worst-case scenario with 620,620 kg.y-1 TN, 82,040 kg.y-1 TP, 7.3 × 1013Cryptosporidium oocysts.y-1 and 9 × 1015 enteric viruses per year. Greater load variability was experienced with decentralised systems, which presumably reflects less reliability in their current operation and maintenance. Overall, catchment water quality is therefore not only affected by sewage disposal methods, but also failure issues. Decentralised system disposal to land may afford a degree of mitigation that can be enhanced, if the degree of failure is reduced.

scholarly journals Constraints to Pearl Millet (Pennisetum glaucum) Production and Farmers’ Approaches to Striga hermonthica Management in Burkina Faso

2021 ◽  
Vol 13 (15) ◽  
pp. 8460
Author(s):  
Armel Rouamba ◽  
Hussein Shimelis ◽  
Inoussa Drabo ◽  
Mark Laing ◽  
Prakash Gangashetty ◽  
...  
Keyword(s):  
Burkina Faso ◽  
Pearl Millet ◽  
Management Practices ◽  
Pennisetum Glaucum ◽  
Control Measures ◽  
Striga Hermonthica ◽  
Soil Conditions ◽  
Management Options ◽  
Central Plateau ◽  
South Central

Pearl millet (Pennisetum glaucum) is a staple food crop in Burkina Faso that is widely grown in the Sahelian and Sudano-Sahelian zones, characterised by poor soil conditions and erratic rainfall, and high temperatures. The objective of this study was to document farmers’ perceptions of the prevailing constraints affecting pearl millet production and related approaches to manage the parasitic weeds S. hermonthica. The study was conducted in the Sahel, Sudano-Sahelian zones in the North, North Central, West Central, Central Plateau, and South Central of Burkina Faso. Data were collected through a structured questionnaire and focus group discussions involving 492 participant farmers. Recurrent drought, S. hermonthica infestation, shortage of labour, lack of fertilisers, lack of cash, and the use of low-yielding varieties were the main challenges hindering pearl millet production in the study areas. The majority of the respondents (40%) ranked S. hermonthica infestation as the primary constraint affecting pearl millet production. Respondent farmers reported yield losses of up to 80% due to S. hermonthica infestation. 61.4% of the respondents in the study areas had achieved a mean pearl millet yields of <1 t/ha. Poor access and the high cost of introduced seed, and a lack of farmers preferred traits in the existing introduced pearl millet varieties were the main reasons for their low adoption, as reported by 32% of respondents. S. hermonthica management options in pearl millet production fields included moisture conservation using terraces, manual hoeing, hand weeding, use of microplots locally referred to as ‘zaï’, crop rotation and mulching. These management techniques were ineffective because they do not suppress the below ground S. hermonthica seed, and they are difficult to implement. Integrated management practices employing breeding for S. hermonthica resistant varieties with the aforementioned control measures could offer a sustainable solution for S. hermonthica management and improved pearl millet productivity in Burkina Faso.

scholarly journals Prevalence and mitigation of aflatoxins in Kenya (1960-to date)

2018 ◽  
Vol 11 (3) ◽  
pp. 341-357 ◽  
Author(s):  
C.K. Mutegi ◽  
P.J. Cotty ◽  
R. Bandyopadhyay
Keyword(s):  
Public Awareness ◽  
Control Measures ◽  
Learning Networks ◽  
Management Options ◽  
Adverse Health Effects ◽  
Documented Information ◽  
Food And Feed ◽  
Safe Food ◽  
Long Term Impact ◽  
The Impact

Aflatoxins are highly toxic metabolites of several Aspergillus species widely distributed throughout the environment. These toxins have adverse effects on humans and livestock at a few micrograms per kilogram (μg/kg) concentrations. Strict regulations on the concentrations of aflatoxins allowed in food and feed exist in many nations in the developing world. Loopholes in implementing regulations result in the consumption of dangerous concentrations of aflatoxins. In Kenya, where ‘farm-to-mouth’ crops become severely contaminated, solutions to the aflatoxins problem are needed. Across the decades, aflatoxins have repeatedly caused loss of human and animal life. A prerequisite to developing viable solutions for managing aflatoxins is understanding the geographical distribution and severity of food and feed contamination, and the impact on lives. This review discusses the scope of the aflatoxins problem and management efforts by various players in Kenya. Economic drivers likely to influence the choice of aflatoxins management options include historical adverse health effects on humans and animals, cost of intervention for mitigation of aflatoxins, knowledge about aflatoxins and their impact, incentives for aflatoxins safe food and intended scope of use of interventions. It also highlights knowledge gaps that can direct future management efforts. These include: sparse documented information on human exposure; few robust tools to accurately measure economic impact in widely unstructured value chains; lack of long-term impact studies on benefits of aflatoxins mitigation; inadequate sampling mechanisms in smallholder farms and grain holding stores/containers; overlooking social learning networks in technology uptake and lack of in-depth studies on an array of aflatoxins control measures followed in households. The review proposes improved linkages between agriculture, nutrition and health sectors to address aflatoxins contamination better. Sustained public awareness at all levels, capacity building and aflatoxins related policies are necessary to support management initiatives.

Microbiological Water Methods: Quality Control Measures for Federal Clean Water Act and Safe Drinking Water Act Regulatory Compliance

2014 ◽  
Vol 97 (2) ◽  
pp. 567-572 ◽  
Author(s):  
Patsy Root ◽  
Margo Hunt ◽  
Karla Fjeld ◽  
Laurie Kundrat
Keyword(s):  
Quality Control ◽  
Drinking Water ◽  
Clean Water Act ◽  
Regulatory Compliance ◽  
Control Measures ◽  
Clean Water ◽  
Safe Drinking Water ◽  
Safe Drinking Water Act ◽  
Specificity And Sensitivity ◽  
Microbiological Methods

Abstract Quality assurance (QA) and quality control (QC) data are required in order to have confidence in the results from analytical tests and the equipment used to produce those results. Some AOAC water methods include specific QA/QC procedures, frequencies, and acceptance criteria, but these are considered to be the minimum controls needed to perform a microbiological method successfully. Some regulatory programs, such as those at Code of Federal Regulations (CFR), Title 40, Part 136.7 for chemistry methods, require additional QA/QC measures beyond those listed in the method, which can also apply to microbiological methods. Essential QA/QC measures include sterility checks, reagent specificity and sensitivity checks, assessment of each analyst's capabilities, analysis of blind check samples, and evaluation of the presence of laboratory contamination and instrument calibration and checks. The details of these procedures, their performance frequency, and expected results are set out in this report as they apply to microbiological methods. The specific regulatory requirements of CFR Title 40 Part 136.7 for the Clean Water Act, the laboratory certification requirements of CFR Title 40 Part 141 for the Safe Drinking Water Act, and the International Organization for Standardization 17025 accreditation requirements under The NELAC Institute are also discussed.

scholarly journals A Systems Analysis Approach to Identifying Critical Success Factors in Drinking Water Source Protection Programs

2019 ◽  
Author(s):  
Hew Cameron Merrett ◽  
Wei Tong Chen ◽  
Jao Jia Horng
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Critical Success Factors ◽  
Success Factors ◽  
Water Source ◽  
Control Measures ◽  
Catchment Management ◽  
Drinking Water Source ◽  
Principle Components Analysis ◽  
Critical Success

The success of source protection in ensuring safe drinking water is centered around being able to understand the hazards present in the catchment then plan and implement control measures to manage water quality risk to levels which can be controlled through downstream barriers. The programs in place to manage source protection are complex sociotechnical systems involving policy, standards, regulators, technology, human factors and so on. This study uses System Theoretic Process Analysis (STPA) to analyze the operational hazards of a typical drinking water source protection (DWSP) program and identify control measures to ensure safe operations. To validate the results a questionnaire was developed and distributed to specialists in DWSP in Taiwan, Australia and Greece. Using Principle Components Analysis (PCA) of the questionnaire responses, the study identified four critical success factors (CSFs) for DWSP. The four factors identified are ‘Policy and Government Agency Support of Source Protection’, ‘Catchment Risk Monitoring and Information’, ‘Support of Operational Field Activities’ and ‘Response to Water Quality Threats’. The results of this study provide insight into the approach of grouping of source protection measures to identify a series of targeted CSF for operational source protection programs. Using CSF can aide catchment management agencies in ensuring that the risk level in the catchment is managed effectively and that threats to public health from drinking water are managed appropriately.

scholarly journals Physicochemical and Microbiological Water Quality Assessment of Aba Waterside River, Aba, Nigeria

2019 ◽  
Vol 3 (1) ◽  
pp. 142-148
Author(s):  
L. O. Bobor ◽  
C. M. Umeh
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Management Strategies ◽  
Oxygen Demand ◽  
Water Quality Monitoring ◽  
Control Measures ◽  
Fecal Coliforms ◽  
Water Quality Control ◽  
Inorganic Substances ◽  
The Impact

The indiscriminate disposal of industrial effluents and solid wastes in surface water bodies is detrimental to humans and aquatic organisms. Water quality monitoring is critical to identify pollutants of concern and develop effective management strategies. Hence, this study was conducted to assess the impact of waste disposal on the water quality of Aba Waterside River, Ogbor hill, Aba. Grab samples were collected upstream, midstream and downstream and some physicochemical and microbiological parameters were analyzed in accordance with standard methods for the analysis of water and wastewater. The results were compared with the Nigerian standard for drinking water quality and the national environmental effluent limitation regulations. Turbidity levels (10 -31mg/l) exceeded the maximum permissible levels for drinking water (5mg/l) and may be associated with higher levels of embedded disease-causing microbes and potentially harmful organic and inorganic substances. The biological oxygen demand midstream (1960mg/l) was remarkably high due to the effluent discharged from the abattoirs at that point. Fecal coliforms (3-198MPN/100ml) were detected in all samples, indicating the presence of other potentially harmful microorganisms. The findings of this study indicate that the water is unsuitable for direct drinking water purposes and stringent water quality control measures should be implemented.

Quantitative risk assessment in the Water Safety Plan: case studies from drinking water practice

2009 ◽  
Vol 9 (2) ◽  
pp. 127-132 ◽  
Author(s):  
Gertjan Medema ◽  
Patrick Smeets
Keyword(s):  
Drinking Water ◽  
Case Studies ◽  
Level Of Detail ◽  
Specific Information ◽  
Water Safety ◽  
Site Specific ◽  
Safety Plan ◽  
Water Safety Plan ◽  
System Assessment

System assessment is the part of the Water Safety Plan that evaluates whether a water supply system is capable of producing drinking water that meets the health-based targets. System assessment can be done at increasing level of detail, requiring more site specific information as the level of detail increases. Four case studies are presented with increasing level of detail, showing the type of information that is required for each of these levels and how each level informs risk management. The first case study shows how a system assessment can be performed without other site specific information than the type of source water and the type of treatment processes. The required data for the system assessment are collected from the large body of literature available. The second case study uses site specific microbial indicator data. The third study uses pathogen data and the fourth case study combines data on pathogens, microbial indicators and process parameters. The case studies show that the level of detail required largely depends on the risk management question.

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