Compared to many parts of the world, the UK has under-invested in its infrastructure in recent decades. It now faces many challenges in upgrading its infrastructure so that it is appropriate for the social, economic and environmental challenges it will face in the remainder of the 21st century. A key challenge involves taking into account the ways in which infrastructure systems in one sector increasingly rely on other infrastructure systems in other sectors in order to operate. These interdependencies mean failures in one system can cause follow-on failures in other systems. For example, failures in the water system might knock out electricity supplies, which disrupt communications, and therefore transportation, which prevent engineers getting to the original problem in the water infrastructure. These problems now generate major economic and social costs. Unfortunately they are difficult to manage because the UK infrastructure system has historically been built, and is currently operated and managed, around individual infrastructure sectors. Because many privatised utilities have focused on operating infrastructure assets, they have limited experience in producing new ones or of understanding these interdependencies. Many of the old national R&D laboratories have been shut down and there is a lack of capability in the UK to procure and deliver the modern infrastructure the UK requires. On the one hand, this makes innovation risky. On the other hand, it creates significant commercial opportunities for firms that can improve their understanding of infrastructure interdependencies and speed up how they develop and test their new business models. This learning is difficult because infrastructure innovation is undertaken in complex networks of firms, rather than in an individual firm, and typically has to address a wide range of stakeholders, regulators, customers, users and suppliers. Currently, the UK lacks a shared learning environment where these different actors can come together and explore the strengths and weaknesses of different options. This makes innovation more difficult and costly, as firms are forced to 'learn by doing' and find it difficult to anticipate technical, economic, legal and societal constraints on their activity before they embark on costly development projects. The Centre will create a shared, facilitated learning environment in which social scientists, engineers, industrialists, policy makers and other stakeholders can research and learn together to understand how better to exploit the technical and market opportunities that emerge from the increased interdependence of infrastructure systems. The Centre will focus on the development and implementation of innovative business models and aims to support UK firms wishing to exploit them in international markets. The Centre will undertake a wide range of research activities on infrastructure interdependencies with users, which will allow problems to be discovered and addressed earlier and at lower cost. Because infrastructure innovations alter the social distribution of risks and rewards, the public needs to be involved in decision making to ensure business models and forms of regulation are socially robust. As a consequence, the Centre has a major focus on using its research to catalyse a broader national debate about the future of the UK's infrastructure, and how it might contribute towards a more sustainable, economically vibrant, and fair society. Beneficiaries from the Centre's activities include existing utility businesses, entrepreneurs wishing to enter the infrastructure sector, regulators, government and, perhaps most importantly, our communities who will benefit from more efficient and less vulnerable infrastructure based services.

The quality of potable water is of vital importance to public health. However, contamination events are observed to occur even in the tiny volume (relative to total supply volume) of the samples collected for regulatory purposes. These events are often unexplained. A possible source of such contamination is pollutant ingress into the distribution system from the surrounding soil and water. Such ingress can occur through the many apertures normally associated with leakage, at times when low or negative pressure conditions occur such as due to hydraulic transients (water hammer).This project will investigate the currently unknown potential for such contaminant ingress into potable water distribution systems by direct measurement utilising a specially developed laboratory facility. Laboratory studies are necessary to address difficulties associated with the short response duration of transient events and the costs, complexity and regulatory unacceptability of field studies. The experimental set up will be full scale and include surrounding ground conditions and a contaminant flow field (for example, an adjacent leaky sewer). Initial studies will investigate the influence of the characteristics of the transients (magnitude, duration etc.) while further studies will investigate the influence of aperture shape, geometry and location.The experiments will provide quantitative evidence of the conditions causing ingress which will be used to develop a new ingress model which, together with existing modelling tools, will enable quantification of the potential for contaminant ingress. The outputs from the new modelling approach will inform improvements to distribution system design, operation and maintenance, management of pollution incidents and ultimately result in improved drinking water quality.The project will be undertaken at the University of Sheffield, with advice and support from Professor Bryan Karney of Toronto University, an international expert in transient analysis and in collaboration with Ecole Polytechnique de Montreal for access to the best currently available relevant field data.

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.

The water industry faces intensifying risks to its water treatment systems through rising dissolved organic matter (DOM) concentrations, especially in upland raw water supplies which provide 70% of the UK's drinking water. Rain and meltwater percolating through soils transports DOM to reservoirs. The water industry has to restrict DOM concentrations to minimise taste and odour problems, reduce the potential for algal growth, and prevent the generation of potentially harmful levels of disinfection bi-products, formed from reactions between DOM and chemical disinfectants. DOM concentrations are increasing primarily as a result of an increase in soil organic matter solubility in response to regional reductions in atmospheric pollutants to soils. However, DOM levels in upland waters are also sensitive to variation, and long-term change, in soil temperatures, amounts and intensity of precipitation, the ionic strength of soil waters, the residence time of reservoirs, and seasalt deposition events during winter storms. The influence of these climate-related effects is increasing as organic matter continues to become more soluble. Currently, the primary industry approach to reduce DOM concentrations is the application of coagulant to precipitate the organic matter from the water, but additional filtration may also be required to remove DOM compounds that are less sensitive to this chemical effect. Both processes have a significant carbon footprint and are estimated to have already cost the industry hundreds of millions of pounds through the installation of new equipment where existing infrastructure was no longer able to deal with rising DOM concentrations. There is a pressing need, therefore, to foster a Climate Change Resilience Community that will combine the extensive expertise of the research and industry communities in the UK in order to address this challenge. FREEDOM-BCCR will develop an entirely new approach to understanding, managing, and planning responses to DOM increases in response to climate change. The community will provide the basis of support for decision making and will deliver adaptive (e.g. infrastructure investment) and mitigative (e.g. land-use interventions) approaches with which to build resilience in the upland water supply. We will augment the capability of a prototype Decision Support tool (DSt), developed by the current NERC FREEDOM Project with support from for Scottish Water, by incorporating catchment-specific climate change projections, predictive models and industry knowledge. This development of the FREEDOM DSt will fill critical knowledge gaps in model functionality including climate change impacts on soil and in-reservoir processing of DOM. We will define operational thresholds for DOM quantity and quality across the treatment chain and combine these to produce forecasts, at a UK scale, of DOM risk to drinking water supply. Proposed activities and respective Work Packages include: generation of UKCP18-based climate change projections using Hydro-JULES downscaled to specific catchments (WP1); Coupling of downscaled climate predictions with catchment and lake/reservoir models to explore the potential impact of climate change in influencing seasonal variation in DOM quantity, quality and vertical distribution in priority intensively monitored drinking water reservoirs and their catchments (WP2); validation of predictions of DOM quantity and quality produced by the FREEDOM DSt, beyond the parameterisation data set from Scottish Water, using hind-casting informed by wider UK industry data (WP3); upscaling application of the FREEDOM-UK DSt to provide predictions of the effects of climate change, land-use change and air pollution scenarios on DOM quantity and quality in other regions of the UK (WP4); and, foster the FREEDOM Climate Change Resilience Community focussing on co-development, application, and show-casing the FREEDOM-UK DSt through a programme of knowledge exchange activities (WP5).

Agricultural practices contribute a significant amount of faecal material onto pasture via direct defecation by grazing livestock and through applications of solid and liquid manures. Managing the spatial and temporal input of this faecal loading to pasture is important in order to minimise the proportion of faecal microorganisms, e.g. E. coli, that may be washed from faecal sources and transferred in runoff to nearby watercourses following rainfall. Contaminated runoff can lead to microbial pollution of our streams, rivers and seas. Scientists, environmental regulators, catchment managers and policy-makers are therefore keen to understand how E. coli survives and moves in the environment with a view that better knowledge and data on the behavioural characteristics of these microorganisms will improve our ability to model and predict their interactions with, and responses to, the world around us. The NERC-funded project ReMOFIO (NE/J004456/1) developed one such model to improve our understanding of the magnitude and spatial distribution of microbial risks in the landscape. The resulting ReMOFIO model predicts levels of microbial risk on agricultural land, based on livestock numbers, farming practices and E. coli survival patterns under environmental conditions (e.g. rainfall and temperature fluctuations). While the model is structurally simple its operation & functionality was not originally designed to maximise uptake by those who would benefit most from its use. In response, the original ViPER project used a participatory approach to bring together a range of stakeholders (regulators, catchment managers, scientists and farm networks) to promote engagement, deliberation and joint decision-making. Through a structured process of knowledge exchange the project team developed a freely-available prototype decision support tool (DST) called ViPER. The ViPER DST provides a user-friendly interface and allows end-users without specific modelling skills or knowledge of a modelling system to take advantage of existing NERC science and modelling capability (e.g. the ReMOFIO model) to understand how, when and where E. coli risks accumulate on agricultural land. However, in its current form, ViPER is unable to evaluate what proportion of that E. coli source on agricultural land will actually end up in rivers and streams following rainfall. In response, the aim of ViPER II is to now transition our prototype DST, which maps E. coli risks at the field, farm and catchment scale, into a user-ready toolkit for providing on-farm advice and guidance in the real world. To do this we will combine the ViPER DST with another freely-available NERC-funded hydrological risk-mapping tool called SCIMAP (NE/C508850/1). SCIMAP was designed to identify the origins of sediment and nutrient pollutants in the landscape and importantly, it maps how runoff can transfer sediment and nutrients across the soil surface and into watercourses. However, SCIMAP currently does not map microbial risks in the landscape because, unlike sediment and nutrients, bacteria such as E. coli accommodate a complex life-cycle and will die-off over time. By contrast, ViPER is able to account for the die-off of E. coli but lacks the capacity to predict E. coli transfer with runoff. An opportunity now exists to integrate two NERC-funded outputs (ViPER & SCIMAP) to deliver an innovative DST for mapping microbial pollution risks in catchment systems and to produce a DST that is greater than the sum of its individual parts. The resulting toolkit will provide added value both to land based assessment of microbial risks, and to the applied interests of environmental regulators and the water industry in the UK (& further afield). This represents the next critical step in ensuring that NERC funded models and data deliver real-world impact through innovative conversion of the underpinning evidence-base into a format that is widely accessible by relevant end-users.