BBuried infrastructure systems are vulnerable to meteorological shocks or extreme weather events, such as floods and droughts due to extreme precipitation, as well as extreme temperatures. Such events can lead to soil movement, thermal contraction and expansion, and sinkholes, among other problems. Despite the urgency, our society is not well prepared for the impacts of these shocks on buried infrastructure. Our understanding of where the risk is and how much it is remains poor, because existing risk assessment tools do not comprehensively consider impacts from both flood water and subsurface moisture/temperature variations. The extent to which the UK's buried infrastructure can cope with a significant weather event, or 'shock', is unclear. Such understanding is crucial for developing effective resilience strategies. This project aims to develop a comprehensive weather-related risk assessment framework for buried infrastructure, which include cables and pipes vital to cities and urban lives. The framework will be applied to understand the potential impacts of weather events and climate change on these infrastructures. The project team will also co-develop adaptation measures with stakeholders to increase resilience to these extreme events. The aim will be accomplished through five interrelated work packages. This includes 1) creating a broad-scale modelling methodology for hydrological conditions; 2) identifying current and future hydrological and meteorological scenarios posing risks to buried infrastructure; 3) employing advanced hydrodynamic modelling and vulnerability analysis to understand how buried pipes and cables respond to varying conditions; 4) integrating the developed models and datasets for a comprehensive risk assessment, and 5) co-developing resilience and adaptation strategies with stakeholders. The project is expected to deliver significant societal and economic impacts. By enhancing decision-making capabilities among infrastructure operators and utility companies, the research can lead to fewer service disruptions, potential cost savings, and increased resilience of infrastructure systems in the face of meteorological shocks and climate change. The project leverages expertise across multiple institutions, including the University of Birmingham, UK Centre for Ecology and Hydrology, and British Geological Survey, to address a critical challenge - the resilience of buried infrastructure to meteorological shocks, demonstrating excellent value for money by capitalising on significant investments in models, facilities, and national datasets. The anticipated outcome of this research program, including the tools and data that will be made available on the DAFNI platform, promises long-term value.

During the last two winters, and that of 2000-01, Chalk catchments of southern England experienced severe groundwater flooding. Rising groundwater tables caused rivers to flow high up-catchment in normally dry valleys, flooding homes and businesses in these locations and further downstream. Groundwater ingress into the sewer network led to restricted toilet use and the overflow of diluted, but untreated sewage to road surfaces, rivers and water courses. Increased sewer flows reaching sewage treatment works caused overspills and the contamination of water flowing into rivers. The water and sewerage company Thames Water Utilities Ltd (TWUL) estimate that they spent in the region of £19m responding to the extreme wet weather of 2013-14 and used a fleet of over 100 tankers. However, the magnitude of the event was so large that these efforts could not stop the discharge of sewage to the environment. A particular challenge in managing groundwater flooding in Chalk catchments is that it can last for weeks to months as they are slow to drain after rainfall stops. In response to these groundwater flooding events TWUL are working to reduce the infiltration of groundwater from the Chalk into sewers, and to understand the risk of groundwater flooding to the network. This involves the development of "Infiltration Reduction Plans", which will be submitted to the Environment Agency, and strategic planning of investment in their infrastructure. This project brings together researchers from the British Geological Survey and Imperial College London, to work in partnership with TWUL infrastructure managers and technical specialists to support this investment planning. The overarching aim of the work is to quantify the scale of the risk of groundwater-induced flooding to the sewer network in a Chalk catchment and to translate this knowledge into options for investment planning. The project builds on recent NERC funded research involving the partners that has developed a series of highly relevant datasets, tools and models. Specifically, we will: (i) quantify the risk of groundwater flooding under current climate using an ensemble of weather sequences generated using the state-of-the art weather generator, GlimClim; (ii) assess changes in the likelihood of flooding under future climate using new probabilistic climate projections; (iii) investigate the propagation, in space and time, of the interaction of groundwater flooding with the sewer network, and where investment should be targeted first to minimise sewer overloading; and (iv) translate this improved understanding into TWUL's investment planning, for example, as part of Ofwat's Asset Management Planning 5-year cycle. The project will use the River Lambourn, Berkshire, which has been impacted by these issues, as a case-study catchment.

The resilience of water systems in the context of climate change, weather extremes, planning and operational decisions is crucial for water infrastructure service delivery and environmental management. In the UK, water systems are under extreme pressure from exceptional droughts like in the summer of 2022, or challenges to manage sewage spills. At the same time, the latest report on river water quality shows that only 14% of rivers in England meet good ecological status. Thus, there is a need to develop resilience assessments to address interlinked challenges of water systems and the environment. This project addresses a critical knowledge gap: What are resilience scenarios for integrated water systems (RIWS) that can be used to evaluate resilience metrics for various stressors, across system components and to inform adaptive planning? The development of RIWS will be supported by the novel Water System Integration Modelling Framework (WSIMOD) developed at the Imperial College London that will be integrated with the DAFNI platform. WSIMOD's flexibility in integrating numerous water system interactions (rural-urban, water supply-wastewater and flow-water quality) and representing a range of water management options with fast simulations times using primarily publicly available data outstand it as an ideal modelling tool for assessing the resilience of integrated water systems. Novel resilience metrics that combine concepts of a critical threshold in performance data with performance metrics evaluation will be informed by Greater London Authority, Thames and Affinity Water and Environment Agency's engagement through participatory workshops. Stressors will be defined as acute (e.g., component failure) and chronic (e.g., climate change) disruptions. The RIWS project aims to develop scenarios that can provide evidence for water companies, planning authorities and environmental regulators on the feasibility of water systems adaptive planning when assessed by resilience metrics, such as structural options (e.g., wastewater treatment plant upgrade) or coordinated operational decisions (e.g., water supply and wastewater systems information exchange to manage river water quality). The project directly contributes to the 'Building a secure and resilient world' strategy focus on 'adaptation to change and robust decision making' and place-based resilience of integrated rural-urban water systems.

The amount of plastic litter in in the environment is growing rapidly. Its presence poses a severe threat to marine and freshwater life. However, at the heart of our knowledge of plastic litter lies a black hole. The location of 99% or more of the plastic litter thought to be in the ocean is unknown. This makes it difficult to propose effective solutions for the problems associated with plastic litter. The main goal of this project is to predict what happens to different types of plastic litter in the environment. To achieve this, the degradation of commonly used plastics will be monitored under controlled laboratory conditions. Experimental methods to produce tiny fragments of plastics made from different polymers will be developed. These will be used to simulate their behaviour in the environment. For example, how quickly they fragment and sink under different conditions and how easily they transfer from water to river sediments. For comparison, plastics which are thought to degrade in a more environmentally-sustainable fashion will also be monitored. Results from these tests will be used to predict the fate of different types of plastics in the environment. They will also allow an assessment of the contribution that promoting sustainable types of plastics can make to solving the problem of plastic litter in the environment.

Manufactured chemicals are essential for the maintenance of public health, food production, and quality of life, including a diverse range of pharmaceuticals, pesticides, and personal care products. The use of these compounds throughout society has led to increasing concentrations and chemodiversity in the environment. Whilst there has been a focus on understanding the impacts of chemicals on a subset of freshwater biodiversity (particularly invertebrates and fish), we understand less about how chemical pollution impacts freshwater microbes. These microbial communities (the 'microbiome') number in the millions to billions of cells per milliliter of water or gram of sediment and form the most biodiverse and functionally important component of freshwater ecosystems. The biogeochemical and ecological functions delivered by freshwater microbes are essential to wider freshwater ecosystem health. The PAthways of Chemicals Into Freshwaters and their ecological ImpaCts (PACIFIC) project will focus on understanding the link between sources of anthropogenic chemicals and their pathways, fate and ecological impacts in freshwater ecosystems, with an emphasis on freshwater microbial ecosystems and the functions they perform. We will investigate the relationship between predicted diffuse and point source chemical pathways and measured chemical concentrations in water and sediments at locations across the Thames and Bristol Avon catchments, chosen to represent gradients of diffuse pollution sources. These locations will be chosen to coincide with Wastewater Treatment Works (WwTWs) to understand how sewage effluent contributes to chemical burden across these gradients. Liquid chromatography coupled with (high resolution) tandem mass spectrometry and QTOF (quadrupole Time-of-Flight) mass spectrometry will be used to perform targeted and untargeted profiling of chemical groups proven and suspected to impact freshwater ecology. A range of microbial community ecosystem endpoints will also be measured at each location to identify the impact of chemical exposure, including bacterial and fungal community composition via DNA sequencing, the expression of nutrient cycling and chemical stress and resistance genes, the production of extracellular enzymes involved with biogeochemical cycling, and the functional gene repertoire of whole microbial communities. We will perform experimental microcosm exposures on freshwater microbial communities, with increasing complexity and realism, deploying high-throughput screening to identify novel chemical groups (and their structural features) with the capacity to restructure these communities. Exemplar microbial community modifying chemicals will be investigated in more detail by applying cutting-edge molecular techniques to determine ecological exposure thresholds that represent different taxonomic and functional aspects of freshwater microbial ecosystems. Novel field-based mesocosms will be used to explore wastewater exposures in more realistic, but controlled settings, allowing us to explore how chemical pollution may interact with other ecological drivers such as nutrients and temperature, and how microbial responses scale up to higher trophic levels and alter ecosystem functioning. Spatially and temporally up-scaled models of diffuse and point source chemical pollution pathways will be combined with novel thresholds developed from the lab and field exposures, to determine chemical threats to freshwater microbes, supporting the development of tools for the better management of the risks of chemical pollution to freshwater ecosystem health. These will be combined with future hydrological, climate, and socio-economic scenarios, informed by responses in our experiments and co-developed with project collaborators, the Environment Agency, to explore future threats to microbial freshwater ecosystems and wider ecosystem health.