John Machell

• PhD
• Senior Research Fellow at The University of Sheffield

It has been widely theorized that water age may be a useful indicator of the quality of water within drinking water distribution networks. However, there is limited evidence of model simulation results being related to empirical water quality (WQ hereafter) data to substantiate the theory. This paper presents the findings of investigations designed...

This paper contemplates the future of utility infrastructure, and considers whether an “All-in-One” approach could supply all necessary utility services to tomorrow's households. The intention is not to propose infrastructure solutions that are currently technically feasible or justifiable, however; the objective is to present visions of future in...

To determine the spatial and temporal variability in the abundance, structure and composition of planktonic bacterial assemblages sampled from a small, looped water distribution system and to interpret results with respect to hydraulic conditions. Water samples were collected from five sampling points, twice a day at 06:00 h and 09:00 h on a Monday...

The spatial distribution of species can be modulated by the existence of some spatial regulatory pattern or by existence of randomization. This study aimed to determine patterns of co-occurrence of epiphytic macroalgae in eight habitats of marine shelf of Cuba. A matrix of presence and absence was made based on values assigned with 1 to the presenc...

Ecological Niche Modelling (ENM) is a tool widely used in ecology to determine environmental conditions and the potential distribution of species. In this article we assess the potential distribution, tolerance limits and similarity niche of macroalgae epiphytes and hosts from the Cuba marine shelf. Using different methods (BIOCLIM, Gower, Maxent a...

The spatial distribution of species can be modulated by the existence of some spatial regulatory pattern or by the existence of randomization. This study aims to determine patterns of co-occurrence of epiphytic macroalgae in eight habitats of marine shelf of Cuba. A matrix of presence and absence was made based on values assigned with 1 to the pres...

In the present, study the potential distribution of 10 epiphytic macroalgae and three host macroalgae of the Cuban marine shelf is modeled for the first time. These macroalgae exhibit characteristics of generalist species due to the similarity and overlap of their modeled ecological niches. Finally, a map of the potential richness of the most commo...

The following set of data provides the systematic list of epiphytic and host macroalgae reported in the scientific literature until 2019. Information is provided on the distribution and type of habitats where epiphytic macroalgae have been registered in Cuba. Finally, the richness of epiphytic macroalgae species per host is offered.

In this data set, bibliographic references that provide information on the epiphytic macroalgae of Cuba are presented. In addition, a set of variables used in the systematic review of the epiphytic macroalgae of Cuba are listed.

The taxonomic composition and diversity of host and epiphytic macroalgal species are important elements in the structure and diversity of marine ecosystems. In this paper, the current state of knowledge and diversity of epiphytic macroalgae and their hosts in Cuba are determined. A systematic review of the scientific literature published from 1900...

Kazakhstan is one of the former soviet union countries with rapidly growing economy over the last decades. It is one of the important world energy and mineral providers, and a rising Asian business and commerce hub in Central Asia. As the country continues to grow it faces serious environmental issues; in particular, poor waste management practices...

This paper is the first comprehensive study to assess public environmental awareness on environmental issues in Nursultan formerly known as Astana), the capital city of Kazakhstan. It employs a survey-based research methodology with a series of crossover assessments. Almost a quarter of the respondents stated that they have already begun waste sepa...

The assessment of the Ganga River System at Rishikesh was investigated at five different sites for three different seasons (summer, winter and monsoon) using comprehensive pollution index (CPI), considering 10 physicochemical parameters such as conductivity, turbidity, total dissolved solids, dissolved oxygen, biochemical oxygen demand, chemical ox...

Water distribution network simulation model output data

In this present study seasonal water quality of River Henwal was conducted in term of the physico-chemical parameters, heavy metals, and plankton composition at four different sites of Chamba, Distt, Tehri Garhwal to observe pollution grade of River Henwal, situated in newly carved state of Uttarakhand. One site was considered as control site out o...

Understanding and managing water quality in drinking water distribution system is essential for public health and wellbeing, but is challenging due to the number and complexity of interacting physical, chemical and biological processes occurring within vast, deteriorating pipe networks. In this paper we explore the application of Self Organising Ma...

Water purity is a vague term. Applied to drinking water, the emphasis of pure can mean ‘free from all types of bacteria and viruses’ as defined by the United States Environmental Protection Agency, or as being ‘wholesome’ when defined within Great Britain. US and British standards are based on the protection of public health. Strictly enforced valu...

Link to full text: http://pubs.rsc.org/en/Content/ArticleLanding/2015/EW/C4EW90001D#!divAbstract Requires registration to access the download Water, energy and food are the pillars upon which society can further advance. The lack of a secure and economical provision of one of these essentials could result in a breakdown of supply, affordability an...

It has been widely theorized that water age may be a useful indicator of the quality of water within drinking water distribution networks. However, there is limited evidence of model simulation results being related to empirical water quality (WQ) data to substantiate the theory. This paper presents the findings of investigations designed to determ...

The evolution of infrastructure is a long journey that requires the concomitant advancement of associated sciences and technologies. Today’s disparate utility infrastructures could be the starting point for such a journey, from where future infrastructure may develop to a degree of perfection that will enable multifunctional use; thereby removing d...

Operational benefits and efficiencies generated using prevalent water industry methods and techniques are becoming more difficult to achieve; as demonstrated by English and Welsh water companies' static position with regards the economic level of leakage. Water companies are often unaware of network incidents such as burst pipes or low pressure eve...

Written by industrial and academic experts, the report reviews the problems of sustainable water across the entire hydrological cycle. It highlighted eight key challenges, and gave recommendations to promote the delivery of technologies, infrastructure, skills and stakeholder education required to create a more sustainable water supply.

Operational benefits and efficiencies generated using prevalent water industry methods and techniques are becoming more difficult to achieve; as demonstrated by English and Welsh water companies’ static position with regards the economic level of leakage. Water companies are often unaware of network incidents such as burst pipes or low pressure eve...

Choice Architecture, Socialisation and Gamification offer tools for cooperative modification of consumption behaviours. The ethics of consumption behaviour modification must be considered in great detail.

The application of complexity science to policy for critical infrastructure systems has never been more important. A number of issues highlight the need for policy to match the complexity of the co-evolving environment: increasing interdependency between utilities, uncontrolled demand leading to over use of diminishing resources, diverse technologi...

Safe, clean drinking water is a foundation of society and water quality monitoring can contribute to ensuring this. A case study application of the CANARY software to historic data from a UK drinking water distribution system is described. Sensitivity studies explored appropriate choice of algorithmic parameter settings for a baseline site, perform...

Presentation to the University of Cranfield Imagination workshop to answer the question: Can a single utility infrastructure deliver all our energy, water and communication needs and wants ? This presentation describes how solar power may be used to meet this challenge.

This paper presents the findings of an investigation into predicted/modeled water age and the associated quality characteristics within a UK drinking water distribution network to determine if there is a discernable link. The hydraulic and water quality software Aquis was used to identify water volumes of different ages, generated by localized dema...

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Sequences were screened for chimeras by the submitter using Bellerophon NA. ##Assembly-Data-START## Assembly Method :: Bioedit v. Version 7.0 Sequencing Technology :: Sanger dideoxy sequencing ##Assembly-Data-END##

Water Distribution Systems is a comprehensive introduction to the topic, covering fundamental concepts and exploring the latest ideas of good practice. Water industry professionals have to address, not only classic design and management problems but also, increasingly, environmental and sustainability requirements and concerns. Drawing together inf...

Water lost through leakage from water distribution networks is often appreciable. As pressure increases on water resources, there is a growing emphasis for water service providers to minimize this loss. The objective of the work presented in this paper was to assess the online application and resulting benefits of an artificial intelligence system...

Hydraulic simulation models of water distribution networks are routinely used for operational investigations and network design purposes. However, their full potential is often never realised because, in the majority of cases, they have been calibrated with data collected manually from the field during a single historic time period and, as such, re...

Hydraulic simulation models of water distribution networks are routinely used for operational investigations and network design purposes. However, their full potential is often never realised because, in the majority of cases, they have been calibrated with data collected manually from the field during a single historic time period and, as such, re...

Mathematical simulation models that are used to provide information about the age of water in potable water distribution networks usually represent the age of water as the flow weighted average age value of the merged flows at a particular location. This approach is questioned and it is argued that age values should not be averaged in this way. Thi...

The implications of water saving initiatives on sewerage & waste water treatment and disposal

Minimising the loss of treated water from water supply systems due to burst and leakage is an ongoing issue for water service providers around the world. Flow monitoring techniques are currently used by the water industry to monitor leakage, generally offline through the application of mass balance type calculations or through observations of chang...

Mapping The Underworld is an EPSRC funded programme consisting of 4 projects and a dissemination network, which was originally initiated by UKWIR under the 'Minimising Street works Disruption' programme. One of the projects, running for a year, investigated the feasibility of new approaches to locating buried assets. These approaches included diffe...

A major UK initiative, entitled Mapping the Underworld (MTU), is seeking to address the serious social, environmental and economic consequences arising from an inability to locate accurately and completely the buried utility service infrastructure without resorting to excavations. One of the four MTU projects aims to develop and prove the efficacy...

In 1997, the Government introduced mandatory leakage targets for water companies, which were designed to (a) preserve water resources, (b) guarantee security of supply, and (c) promote efficiency within the water industry. It is intended that each target should reflect the individual situation of the company and that the targets should be achievabl...

This research demonstrates the application of Artificial Neural Networks (ANNs) and Fuzzy Logic for the detection and classification (leakage rate) of pipe bursts from DMA flow data. In contrast to existing methodologies that are reliant on human data analysis and interpretation, this automated approach is able to provide efficient and consistent a...

Changes and deterioration in water quality occur during the passage of potable water through distribution systems. Resulting issues include taste and odour, high corrosion rates, precipitation, discolouration, disinfection by-product formation, and biological activity. While the direct simulation of the behaviour, reactions and interaction leading...

Current practice for the management and extraction of meaningful information from available data, to inform understanding of water supply system performance, is limited, time consuming and of inadequate accuracy. This is primarily due to reliance on human data analysis and interpretation, which is unfeasible for the volume and complexity of data in...

Yes This paper describes the design, development, deployment and performance assessment of a prototype system for monitoring the “health” of a water distribution network based on the temperature distribution and time-dependent variations in temperature across the network. It has been found that the water temperature can reveal unusual events in a w...

Thesis (Ph.D.)--University of Sheffield, 2003.

This paper presents research into the application of artificial neural networks (ANNs) for analysis of data from sensors measuring hydraulic parameters (flow and pressure) of the water flow in treated water distribution systems. Two neural architectures (static and time delay) are applied for time series pattern classification from the perspective...

Current practice for the management and extraction of meaningful information from available data, to inform understanding of water supply system performance, is limited, time consuming and of inadequate accuracy. This is primarily due to reliance on human data analysis and interpretation, which is unfeasible for the volume and complexity of data in...

This paper presents a performance assessment of two failure sensors for the detection of events in a pipeline distribution system. These sensors identify abnormal events on the basis of water opacity and differential temperature. The opacity sensor measures the cloudiness of the water, which is assumed to be dependent on water flow rate and turbule...

Yes This paper describes an automated event detection and location system for water distribution pipelines which is based upon low-cost sensor technology and signature analysis by an Artificial Neural Network (ANN). The development of a low cost failure sensor which measures the opacity or cloudiness of the local water flow has been designed, devel...

This paper presents research into analysis and data fusion for sensors measuring hydraulic parameters (flow and pressure) of the pipeline water flow in treated water distribution systems. An artificial neural network (ANN) based system is used on time series data produced by sensors to construct an empirical model for the prediction and classificat...

This paper describes the design and development of a new sensor which is low cost to manufacture and install and is reliable in operation with sufficient accuracy, resolution and repeatability for use in newly developed systems for pipeline monitoring and leakage detection. To provide an appropriate signal, the concept of a "failure" sensor is intr...

This paper describes how hydraulic and water quality data from a distribution network may be used to provide a more efficient leakage management capability for the water industry. The research presented concerns the application of artificial neural networks to the issue of detection and location of leakage in treated water distribution systems. An...

In the calibration procedure adopted for most hydraulic network models, parameters are adjusted to ensure that measured and computed pressures are approximately equal. Little emphasis is placed on confirmation of a correct flow rate distribution. Such procedures can therefore promote erroneous flow rate solutions. However, it is becoming increasing...

Water colour is a problem in the upland water-gathering grounds of the UK. It has shown considerable variation over recent years and this needs to be put into the longer-term context. In order to do this, factors to convert water colour measured in absorbance units per metre (Au/m) to Hazen units are presented for ten sites in the Yorkshire region...

Distribution network models are commonly calibrated based on the agreement between computed pressures and pressures measured during field surveys. Other than via a global flow rate balance, little consideration is given to the accuracy of the temporal and spatial distribution of flow rate. However, the use of water quality models is becoming more w...

The possible role of artificial neural networks to model the impact of the distribution network on water quality under different patterns of demand and for different source water qualities is considered and contrasted against a deterministic approach. To investigate the feasibility of this technique, a case study is presented of the prediction of o...

The modelling of water distribution networks has, traditionally, been either a System Engineering exercise or a Post Analysis function carried out in an off-line environment. This form of system modelling is essentially steady state in nature, a condition not normally experienced in water distribution systems which are dynamic under normal operatin...