3 Projects, page 1 of 1
The majority of countries around the world maintain a disinfectant residual to control planktonic microbial contamination and/or regrowth within Drinking Water Distribution Systems (DWDS). Conversely, some European countries prohibit this practice because the residuals react to create disinfection by-products, which are regulated toxins with carcinogenic effects. Critically, the impact of disinfectant residuals on biofilms is unknown, including their role in creating a preferential environment for pathogens. Biofilms grow on all surfaces; they are a matrix of microbial cells embedded in extracellular polymeric substances. With biofilms massively dominating the organic content of DWDS, there is a need for a definitive investigation of the processes and impacts underlying DWDS disinfection and biofilm interactions such that all the risks and benefits of disinfection residual strategies can be understood and balanced. This balance is essential for the continued supply of safe drinking water, but with minimal use of energy and chemicals. The central provocative proposition is that disinfectant residuals promote a resistant biofilm that serves as a beneficial habitat for pathogens, allowing pathogens to proliferate and be sporadically mobilised into the water column where they then pose a risk to public health. This project will, for the first time, study and model the impact of disinfectant residual strategies on biofilms including pathogen sheltering, proliferation, and mobilisation to fill this important gap in DWDS knowledge. The potential sources of pathogens in our DWDS are increasing due to the ageing nature of this infrastructure, for example, via ingress at leaks during depressurisation events. Volumes of ingress and hence direct exposure risks are small but could seed pathogens into biofilm, with potential for proliferation and subsequent release. An integrated, iterative continuum of physical experiments and modelling is essential to deliver the ambition of the proposed research. We will make use of the latest developments in microbiology, internationally unique pilot scale experimental facilities, population biology and microbial risk assessment modelling to understand the interactions between the disinfection residuals, biofilms, pathogens and hydraulics of drinking water distribution systems. This research will combine globally renowned expertise in mathematical modelling, drinking water engineering, quantitative microbial risk assessment, and molecular microbial ecology to deliver this ambitious and transformative project. If the central proposition is proven, then current practice in the UK and the majority of the developed world could be increasing health risks through the use of disinfectant residuals. The evidence generated from this research will be central to comprehensive risk assessment. A likely outcome is that by testing the hypothesis, we will prove under what conditions the selective pressures on biofilms are unacceptable, and in so doing understand and enable optimisation of disinfection residuals types and concentrations for different treated water characteristics. Although focused on the impacts of disinfectant residuals and pathogens, the research will also generate wider knowledge of biofilm behaviour, interactions and impacts between biofilms and water quality within drinking water distribution systems in general and relevant to other domains. The impact of this research will be to deliver a step change in protecting public health whilst minimising chemical and energy use through well informed trade-offs between acute drinking water pathogen (currently unknown) and chronic disinfectant by-product (known and increasing) exposure. The ultimate beneficiaries will be the public, society and economy due to the intrinsic link between water quality and public health.
Globally, one in four cities is facing water stress, and the projected demand for water in 2050 is set to increase by 55%. These are significant and difficult problems to overcome, however this also provides huge opportunity for us to reconsider how our water systems are built, operated and governed. Placing an inspirational student experience at the centre of our delivery model, the Water Resilience for Infrastructure and Cities (WRIC) Centre for Doctoral Training (CDT) will nurture a new generation of research leaders to provide the multi-disciplinary, disruptive thinking to enhance the resilience of new and existing water infrastructure. In this context the WRIC CDT will seek to improve the resilience of water infrastructure which conveys and treats water and wastewater as well as the impacts of water on other infrastructure systems which provide vital public services in urban environments. The need for the CDT is simple: Water infrastructure is fundamental to our society and economy in providing benefit from water as a vital resource and in managing risks from water hazards, such as wastewater, floods, droughts, and environmental pollution. Recent water infrastructure failures caused by climate change have provided strong reminders of our need to manage these assets against the forces of nature. The need for resilient water systems has never been greater and more recognised in the context of our industrial infrastructure networks and facilities for water supply, wastewater treatment and urban drainage. Similarly, safeguarding critical infrastructure in key sectors such as transport, energy and waste from the impacts of water has never been more important. Combined, resilience in these systems is vitally important for public health and safety. Industry, regulators and government all recognise the huge skills gap. Therefore there is an imperative need for highly skilled graduates who can transcend disciplines and deliver innovative solutions to contemporary water infrastructure challenges. Centred around unique and world leading water infrastructure facilities, and building on an internationally renowned research consortium (Cranfield University, The University of Sheffield and Newcastle University), this CDT will produce scientists and engineers to deliver the innovative and disruptive thinking for a resilient water infrastructure future. This will be achieved through delivery of an inspirational and relevant and end user-led training programme for researchers. The CDT will be delivered in cohorts, with deeply embedded horizontal and vertical training and integration within, and between, cohorts to provide a common learning and skills development environment. Enhanced training will be spread across the consortium, using integrated delivery, bespoke training and giving students a set of unique experiences and skills. Our partners are drawn from a range of leading sector and professional organisations and have been selected to provide targeted contributions and added value to the CDT. Together we have worked with our project partners to co-create the strategic vision for WRIC, particularly with respect to the training needs and challenges to be addressed for development of resilience engineers. Their commitment is evidenced by significant financial backing with direct (>£2.4million) and indirect (>£1.6million) monetary contributions, agreement to sit on advisory boards, access to facilities and data, and contributions on our taught programme.
The surface urban transport infrastructures - our roads, cycle ways, pedestrian areas, tramways and railways - are supported by the ground, and hence the properties of the ground must control to a significant degree their structural performance. The utility services infrastructure - the pipes and cables that deliver utility services to our homes and which supports urban living - is usually buried beneath our urban streets, that is it lies below the surface transport infrastructure (usually roads and paved pedestrian areas). It follows that streetworks to install, replace, repair or maintain these utility service pipes or cables using traditional trench excavations will disrupt traffic and people movement, and will often significantly damage the surface transport infrastructure and the ground on which it bears. It is clear, therefore, that the ground and physical (i.e. utility service and surface transport) infrastructures exist according to a symbiotic relationship: intervene physically in one, and the others are almost inevitably affected in some way, either immediately or in the future. Moreover the physical condition of the pipes and cables, of the ground and of the overlying road structure, is consequently of crucial importance in determining the nature and severity of the impacts that streetworks cause. Assessing the Underworld (ATU) aims to use geophysical sensors deployed both on the surface and inside water pipes to determine remotely (that is, without excavation) the condition of these urban assets. ATU builds on the highly successful Mapping the Underworld (MTU) project funded by EPSRC's first IDEAS Factory (or sandpit) and supported by many industry partners. The MTU sandpit brought together a team that has grown to be acknowledged as international leaders in this field. ATU introduces leaders in climate change, infrastructure policy, engineering sustainability and pipeline systems to the MTU team to take the research into a new sphere of influence as part of a 25-year vision to make streetworks more sustainable. ATU proposes to develop the geophysical sensors created in MTU to look for different targets: indications that the buried pipes and cables are showing signs of degradation or failure, indications that the road structure is showing signs of degradation (e.g. cracking, delamination or wetting) and indications that the ground has properties different to unaltered ground (e.g. wetted or eroded by leaking pipes, loosened by local trench excavations, wetted by water ingress through cracked road structures). For example, a deteriorated (fractured, laterally displaced, corroded or holed) pipe will give a different response to the geophysical sensors than a pristine pipe, while wetting of the adjacent soil or voids created by local erosion due to leakage from a water-bearing pipe will result in a different ground response to unaltered natural soil or fill. Similarly a deteriorated road (with vertical cracks, or with a wetted foundation) will give a different response to intact, coherent bound layers sitting on a properly drained foundation. Taking the information provided by the geophysical sensors and combining it with records for the pipes, cables and roads, and introducing deterioration models for these physical infrastructures knowing their age and recorded condition (where this information is available), will allow a means of predicting how they will react if a trench is dug in a particular road. In some cases alternative construction techniques could avert serious damage (e.g. water pipe bursts, road structural failure requiring complete reconstruction) or injury (gas pipe busts). Making this information available will be achieved by creating a Decision Support System for streetworks engineers. Finally, the full impacts to the economy, society and environment of streetworks will be modelled in a sustainability assessment framework so that the wider impacts of the works are made clear.