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The potential to reduce the risks posed by tailings dams using satellite-based information
Get PDFThe failures of tailings dams, used to store waste from mining operations, pose a significant risk to the health of people and the environment, especially in many low income countries where the extractive industry makes a significant contribution to the nation's wealth. Recently the rate of failure of tailings dams has increased. The demand for raw materials and increases in intense rainfall as a result of climate change will exacerbate this issue in the future. The monitoring of tailings dams is essential to reduce their probability of failure. Virtually all the recent tailings dams failures were preventable. However, there is generally a lack of transparency and accountability for these structures by mining companies. In the past 10 years an increase in the global coverage and accuracy of Earth Observation (EO) based information has made it technically possible to use EO-based data to remotely monitor critical aspects of tailings dams, such as their deformation and the leakage of pollutants. This paper describes the development of an EO-based service, being piloted in Peru, which would allow tailings dams to be monitored cost effectively, and also help to forecast any potentially risk inducing behaviour from tailings dams several weeks in advance. Many regulatory bodies in low income countries do not have the resources to adequately monitor mining operations. A low cost EO-based system could improve the transparency and safety of tailings dams, allowing timely preventative interventions to be made where the probability of failure is found to be high
Evolution of joint probability methods in coastal engineering practice in the UK
No full textThis paper outlines the evolution of joint probability methods in the design and assessment of sea defence structures in the UK, together with the key drivers for these different methods. It highlights why and how the joint exceedance curve techniques were developed initially from the late 1980s and early 1990s, as well as the reasons for the later development of the Join-Sea software system in the mid-1990s, as well as more recently, the implementation of more robust multivariate statistical approaches. The differences between these techniques are outlined, as well as potential errors accounting for how these different techniques are applied to assess different sea defence response functions
Barchan vs Monopile: what happens when a barchan dune finds an obstacle in its path?
No full textThe impact of barchan dunes colliding with one another has been well observed, understood and modelled. But what happens when there is an immobile obstacle, an Offshore Wind Farm (OWF) monopile foundation, in one’s path? At the case study OWF a monopile was installed ~45 m downstream of the slip-face of an approaching barchan dune. Six bathymetric surveys, over a 20 year period, are analysed capturing the impact of the monopile on the dune’s evolution. The dune migrated relatively consistently, at a rate of 20 to 25 m/year. The re-appearance of the jack-up rig spudcan footprints in the wake of the barchan indicates that the dune does not exchange material with the seafloor and that the sedimentary composition of the two must be distinct
Minimising the risks of tailings dams with remote sensing data
Get PDFTailings dams are used to store toxic mine waste and effluent. Their failure rate is estimated to be more than two orders of magnitude greater than that of conventional water retention dams, causing loss of lives, irreversible damages to ecosystems and large economic damages.
There is a need for a cost effective service to monitor operational, closed and abandoned tailings dams, especially those in remote locations, to help forecast potentially catastrophic failures
Using spatio-temporal feature type structures for coupling environmental numerical models to each other and to data sources
Get PDFThe European Marine Observation and Data Network (EMODnet): Visions and Roles of the Gateway to Marine Data in Europe
No full textMarine data are needed for many purposes: for acquiring a better scientific understanding of the marine environment, but also, increasingly, as marine knowledge for decision making as well as developing products and services supporting economic growth. Data must be of sufficient quality to meet the specific users' needs. It must also be accessible in a timely manner. And yet, despite being critical, this timely access to known-quality data proves challenging. Europe's marine data have traditionally been collected by a myriad of entities with the result that much of our data are scattered throughout unconnected databases and repositories. Even when data are available, they are often not compatible, making the sharing of the information and data aggregation particularly challenging. In this paper, we present how the European Marine Observation and Data network (EMODnet) has developed over the last decade to tackle these issues. Today, EMODnet is comprised of more than 150 organizations which gather marine data, metadata, and data products and make them more easily accessible for a wider range of users. EMODnet currently consists of seven sub-portals: bathymetry, geology, physics, chemistry, biology, seabed habitats, and human activities. In addition, Sea-basin Checkpoints have been established to assess the observation capacity in the North Sea, Mediterranean, Atlantic, Baltic, Artic, and Black Sea. The Checkpoints identify whether the observation infrastructure in Europe meets the needs of users by undertaking a number of challenges. To complement this, a Data Ingestion Service has been set up to tackle the problem of the wealth of marine data that remain unavailable, by reaching out to data holders, explaining the benefits of sharing their data and offering a support service to assist them in releasing their data and making them available through EMODnet. The EMODnet Central Portal (www.emodnet.eu) provides a single point of access to these services, which are free to access and use. The strategic vision of EMODnet in the next decade is also presented, together with key focal areas toward a more user-oriented service, including EMODnet for business, internationalization for global users, and stakeholder engagement to connect the diverse communities across the marine knowledge value chain
Exploring regional water transfers to secure future water supply: a case study from the UK
No full textWater companies in the UK are required to produce long-term plans of water resources for their supply area every five years, detailing how they will maintain secure and sustainable supplies, taking account of social and environmental impacts as well as economic costs. As a result, the water environment is highly regulated to ensure competing demands are satisfied.
Approximately a quarter of the UK population lives in the south-east of the country where six separate water companies supply water. The population of this region is projected to grow at a rate exceeding the national average, with some areas predicted to face water supply deficits in the near future. Therefore, should no action be taken, the demand for water is forecast to increase whilst the availability of water resources decreases due to climate change and the reduction of some licences to improve the freshwater environment. A recent exercise highlighted the very real difficulties that would be faced in implementing existing severe drought response and mitigation measures in practice in response to a drought affecting the south-east.
A key conclusion from the WaterUK long term planning framework report was that large-scale inter-regional transfers of water could offer the best value for money. Strategic schemes to transfer water from areas of projected water security to those of projected water scarcity are actively being explored. OFWAT, the financial regulator of the UK water industry, expects a fully informed decision to be made on which scheme, if any, to progress with, by 2022. These potential transfers pose several regulatory, environmental, and operational challenges. For example: How can water companies be confident that the water will be available when they need it?; How can regulators test the scheme without damaging the environment?; How can all stakeholders agree to the data and analytical approaches being used to assess the scheme?.
We have undertaken several studies to support the assessment of the feasibility of a transfer of water from reservoirs in the upper reaches of the River Severn in Wales to the south-east via the River Severn and the River Thames. As part of this work, hydrological and water resources models of both catchments were developed for the study area exceeding 20,000 km2. These models brought to light uncertainties across key flow gauging stations and the challenges of operating a scheme in a highly regulated river network.
Using these models, and a series of drought libraries developed using both synthetic and stochastic time series, an assessment of the likelihood of coincident drought in both catchments was undertaken. Drought events in the River Thames which would trigger the need requirement for additional resources via a strategic scheme were mapped to the River Severn. The assessment highlighted conditions under which a water supply system with several sources of supply could increase its resilience to drought.
To understand the net gain of the scheme, the catchments were divided into key reaches and factors such as attenuation, groundwater-surface water interactions, and travel time were systematically assessed. The results of this study concluded that the key source of uncertainty associated with this strategic scheme were not physical processes, but rather were attributed to how the scheme would be operated and regulated.
A scoping phase of work is currently being planned with regulators across the two catchments, water companies, and stakeholders to physically test the scheme. Our presentation will discuss the technical approach, challenges, and results of these studies, as well as an overview of the perspectives of water companies, regulators, and stakeholders
Integrating climate resilience in the water sector in the Caribbean: Moving from regional to national action
Get PDFClimate-sensitive sectors such as water are central to sustainable development in the Caribbean. Strengthening regional and national capacity to respond to climate change, to mainstream climate resilience, and to design transformative sector- wide interventions is therefore a key priority under the ACP-EU-CDB National Disaster Risk Management (NDRM) programme.
As part of this initiative, Phase I of the “Planning for the Integration of Climate Resilience in the Water Sector in the Caribbean project” (The Project) produced a package of training materials, tools, guidelines and technical notes to help water professionals and other practitioners mainstream climate resilience in the water sector. The training materials provide a framework to strengthen water sector resilience across multiple facets including assets and infrastructure, policies, plans, strategies and institutions. The training materials were developed and refined through country case study applications in Grenada and St. Kitts & Nevis. A regional Training of Trainers event bringing together representatives from the borrowing member countries (BMCs) of the Caribbean Development Bank (CDB) was subsequently held to improve the capacity of national professionals and practitioners to identify, plan and implement climate resilient development pathways in the water sector. Phase II of The Project subsequently applied the training materials, tools, guidelines and technical notes to two new case study countries, Dominica and Antigua & Barbuda. These additional pilot applications further demonstrated the applicability of the approaches in countries where the water supply and services were severely affected by Hurricanes Maria (Dominica) and Irma (Antigua & Barbuda) in September 2017.
This paper showcases the outcomes and deliverables of The Project, highlights lessons learned during applications in the case study countries and takes a critical look at actions required to support the shift from regional to national actions to accelerate the integration of climate resilience across CDB’s BMCs
International examples of private funding and financing of FCERM
No full textDEFRA commissioned a Quick Scoping Review (QSR) addressing the question of what international examples there might be of private funding of FCERM management measures. The QSR required a literature and web search coupled with interviews with relevant professionals. Our QSR revealed that while there is a significant body of evidence that shows a widespread aspiration to have private funding of such defences and measures there are only limited examples where this had been put into practice. Where international examples were found they were often found to be either site specific or a function of the capacity of local authorities to obtain private funding. This presentation will describe the methodology used, the context of the QSR, drawing on the work of other researchers in developing the aspiration for shared funding of FCERM, and will examine UK examples. The primary focus will be on examples of private funding from the United States, Australia, Malaysia and Spain. Some conclusions are drawn as to what has enabled the success of private funding of FCERM and what inhibits the uptake of private funding. Finally there is a discussion of the applicability of the methods and approaches in the discussed examples to the United Kingdom context
Active System Management for drainage networks and river systems (Case studies of Flow and Flood forecasting systems around the world)
No full textUptake of Active System Management (ASM) has been slow despite increasing evidence of the potential benefits that it can bring to water decision makers.
ASM has been in various stages of implementation for a number of years, with a number of utilities (water companies) performing pilot studies to assess their benefits. However, the slowness in the uptake of ASM techniques is the result of a number of ‘blockers’, including, limited awareness of the potential benefits, the perception that its implementation is complex and risky, the perceived cost of its implementation, and the data requirements for the system.
While coming from a UK perspective this paper will address typical blockers, using illustrations of available ASM techniques and examples of their use and demonstrate their applicability in a global context. It will describe a road map explaining the development process for ASM, which can be applied to help address a range of operational problems and customer requirements. The paper will present a balanced view of the available tools for system development. Data requirements will be discussed, in considering the types of observed and forecast data needed to support ASM, and the methods of enabling reliable and high quality live data feeds.
A significant advantage of ASM is its trend for using continuous and spatial rainfall records rather than using design rainfall when developing system models. Continuous rainfall records permit a better understanding of the catchment as they allow for antecedent conditions to be used as well as acknowledging that a defined return period event does not necessarily sit in isolation from other events; spatial rainfall data present a clear picture of the variability of rainfall across the catchment. ASM models are implicitly continuous simulations with each forecast run saving a state that it used to initialise subsequent forecast runs.
Some examples that demonstrate the key applications and benefits of ASM will be presented (including real cases studies in countries like USA, UK, Malaysia and China): Forecasting and mitigation of CSOs; Forecasting and mitigation of flooding (for both urban and rural catchments); Safe management of multi-purpose spaces (which will be flooding during extreme events); Water resources applications (Flow forecasting systems for dam releases); Managing flows to WWTW through better use of inherent network capacity rather than costly development of new infrastructure; Identifying locations where system performance is suboptimal, such as blockages, sedimentation, and cross connections.
This presentation will argue that actively managing systems in this way can offer significant positive operational, financial, environmental, customer service and planning outcomes