Using Mass Flow Analysis (MFA) to estimate the performance of scenarios for a rainwater harvesting system in Tyseley, Bi...Published: 27 June 2016 by WITPRESS LTD. in Urban Water III
Highlights•A sustainable underground use resilience evaluation (SUURE) framework is presented.•Geoscientific information is presented through fuzzy logic analysis using ARCGIS.•Quantification of spatial and temporal impacts of a Multi Utility Tunnel is assessed.•Flush-fitting MUT was found to be having the highest resilience index ratio (0.739). AbstractUrban sub-surface environments have consistently been used to house a wide variety of urban infrastructure, but often developed in a relatively haphazard way. An important aspect to overcome this is an enriched understanding of the current and potential future uses. Therein Geoscientific information should be considered indispensable, if this space is to be developed in a resilient and sustainable way. This will require a clear understanding of what is or could be located within underground space, together with its properties, in order to assess its true potential as an urban resource. This information will inform urban developmental choices allowing sustainable and resilient development of underground space use to take place regardless of what the future may hold. However, such information needs to be integrated into decision support systems for conventional types of underground construction, in order for any development to occur in a consistent and manageable way.This paper presents the development of a new sustainable underground use resilience evaluation (SUURE) framework that will allow the quantification of both spatial and temporal impacts of today’s underground urban (re)development solutions, in light of future economic, environmental and social changes. The framework uses a broad range of plausible, yet divergent future scenarios in order to ensure core objectives of sustainability and resilience are met. Within this paper it is used to evaluate the utilisation of Multi-Utility-Tunnels – MUT’s (i.e. flush-fitting, shallow and deep) in Birmingham Eastside, UK, as an alternative utility placement technique to traditional (open-cut) trenching. The flush-fitting MUT was found to be having the highest overall baseline (i.e. present-day) performance with a resilience index ratio of 0.739 (mean value), the shallow MUT came second at 0.656, and the deep MUT came last at 0.212.
The challenge of feeding nine billion people by 2050, in a context of constrained resources and growing environmental pressures posed by current food production methods on one side, and changing lifestyles and consequent shifts in dietary patterns on the other, exacerbated by the effects of climate change, has been defined as one of the biggest challenges of the 21st century. The first step to achieve food security is to find a balance between the growing demand for food, and the limited production capacity. In order to do this three main pathways have been identified: employing sustainable production methods in agriculture, changing diets, and reducing waste in all stages of the food chain. The application of an energy, water and food nexus (EWFN) approach, which takes into account the interactions and connections between these three resources, and the synergies and trade-offs that arise from the way they are managed, is a prerequisite for the correct application of these pathways. This work discusses how Life Cycle Assessment (LCA) might be applicable for creating the evidence-base to foster such desired shifts in food production and consumption patterns.
A Novel Methodology for the Application of Middle-Out, Model-Based Systems Engineering Techniques for City Waste Managem...Published: 29 October 2015 by Wiley in INCOSE International Symposium
A holistic approach to urban development is required to meet global sustainability goals. Part of the challenge involves finding an effective response to the increasing volumes of solid waste being generated in cities. The European Commission has developed a thematic strategy, and issued directives, on the prevention and recycling of waste. The United Kingdom has introduced legislation in line with these, and is working to develop its own waste management strategies against a very complex background. This paper describes a novel methodology for the application of middle-out, model-based systems engineering techniques to help with this, using the city of Birmingham in the United Kingdom as an example. The methodology creates repeatable and objective models of existing waste management systems and links them to city management accounts to provide a foundation for the design of new and improved systems and business models.
Well-functioning 'liveable' cities should be sustainable and their consumption of natural resources and production of waste must fit within the capacities of the local, regional and global ecosystems. It is increasingly becoming suggested that an Urban Metabolism (UM), approach could help city decision-makers (e.g. planners) take account of numerous critical influencing factors related to the inward outward flow(s) of natural resources (e.g. food, water and energy) and accumulation of waste. The paper identifies the precursory step for any UM study (Mass Flow Analysis - MFA) and applies it to a case study (Birmingham, UK) in order to show how it could contribute to the measurement, assessment and understanding of liveability, defined as 80% reduction in carbon (from 1990 levels); resource secure (an ethos of One planet living); with maintained or enhanced wellbeing. By provided focus upon an individual resource stream (i.e. water) at multiple scales (city to individual) it is shown that MFA can be used as a starting point to develop realistic and radical engineering solutions. However further work is required for it to be truly reflective of broader aspects of urban liveability.
The food/water/energy nexus is the study of the interactions and connections between these three resources, the synergies and tradeoffs that arise from the way they are managed, and the potential areas of conflict. The core of nexus thinking is that no good results can be achieved from considering these resources independently, which means that food security cannot be achieved in a context of either/both water or/and energy insecurity. All three elements have to be assured to foster sustainability, resilience, prosperity and peace. In this paper attention is focused on the challenges posed by this nexus on achieving food security, which is embodied in the first Millennium Development Goal (MDG), which seeks to halve the number of hungry people in the world between 1990 and 2015. The primary aim of the paper is to identify how the nexus mentality underlies most of the pathways that have been proposed to achieve this goal. It argues that significant shortfalls exist and need to be addressed: there is still no generally accepted definition, and identifiable metrics for assessing the extent to which a food system fosters food security are lacking. Such metrics are necessary when evaluating alternative strategies and negotiating trade-offs therein.
Rainwater Harvesting: Trade-offs Between Pluvial Flood Risk Alleviation and Mains Water Resource SavingsPublished: 31 October 2014 by MDPI AG in The 4th World Sustainability Forum
Stormwater run-off generally refers to pluvial, i.e. rainfall related, water that does not soak into the ground at the point at which it falls. The volume and timing of stormwater run-off, specifically from roof tops is highly important to urban flood control and its capture has the potential for non-potable uses within (e.g. for WC flushing and for washing machines) and outside the home (e.g. car washing and garden watering). The former runs a risk of flash floods where local and downstream stormwater (or combined sewer) systems become overburdened in times of extreme rainfall events. The later will influence potential future urban water supplies, which is particularly important at time(s) where mains water availability is scarce (e.g. times of drought or when the national demand for water in the UK increases beyond supply capabilities) population. Rainwater harvesting (RWH) systems can benefit flood risk and water supply however their ability to do either / both is dependent on the subtleties of filling and emptying (i.e. stored water volume or spare storage capacity) which are not fully understood, particularly in peak flow events. Through the use of five years worth of daily rainfall data for Birmingham (2007 - a record breaking year for UK flooding, to 2011) these subtleties are investigated through a sensitivity type analysis of tank size, occupancy rates and technology efficiency. The results show that RWH tanks sized according to BS8515 would not have been capable of capturing rainfall that fell in peak flow events. Moreover not all yearly non-potable demands would have been met. If tanks were over-sized by a factor of 3.0 (i.e. use the larger of 15% yearly non-potable demands or rainfall) this would have been sufficient to meet all demands and eliminate roof-top run-off.
The national demand for water in the UK is predicted to increase, exacerbated by a growing UK population, and home-grown demands for energy and food. When set against the context of overstretched existing supply sources vulnerable to droughts, particularly in increasingly dense city centres, the delicate balance of matching minimal demands with resource secure supplies becomes critical. When making changes to "internal" demands the role of technological efficiency and user behaviour cannot be ignored, yet existing benchmarking systems traditionally do not consider the latter. This paper investigates the practicalities of adopting a domestic benchmarking system (using a band rating) that allows individual users to assess their current water use performance against what is possible. The benchmarking system allows users to achieve higher benchmarks through any approach that reduces water consumption. The sensitivity of water use benchmarks are investigated by making changes to user behaviour and technology. The impact of adopting localised supplies (i.e., Rainwater harvesting—RWH and Grey water—GW) and including "external" gardening demands are investigated. This includes the impacts (in isolation and combination) of the following: occupancy rates (1 to 4); roof size (12.5 m2 to 100 m2); garden size (25 m2 to 100 m2) and geographical location (North West, Midlands and South East, UK) with yearly temporal effects (i.e., rainfall and temperature). Lessons learnt from analysis of the proposed benchmarking system are made throughout this paper, in particular its compatibility with the existing Code for Sustainable Homes (CSH) accreditation system. Conclusions are subsequently drawn for the robustness of the proposed system.
Due to the adoption of short-term planning cycles and the requirement for lowest initial construction costs, the conventional method for utility installation and maintenance in the UK is via open-cut. When taking a long-term sustainability perspective there is a growing body of evidence which indicates that this method is socially disruptive, environmentally damaging and significantly more expensive, i.e. unsustainable. One long-term solution to this problem could be the adoption of Multi-Utility Tunnels (MUTs); a tunnel that co-locates more than one utility underground facilitating their subsequent repair and renewal while eliminating the need for continuous surface excavation. Unfortunately considerably higher short-term direct costs remain a significant barrier to adoption of MUTs. However, there is a lack of research to show where the economic tipping point between the two methods occurs and how it might be influenced by utility type, pipe number (i.e. density), pipe diameter, number of excavation and reinstatement (E&R) procedures avoided, location (i.e. undeveloped, suburban and urban areas), and the choice of MUT being adopted (i.e. flush-fitting, shallow and deep). This paper aims to fulfil this research need by investigating the effect of these influences on the economic viability of various types of MUTs. The results indicate that MUTs can provide a more economically sustainable method of utility placement in all three local contexts, with the tipping points occurring where street works are likely more frequent and/or where utility density is high.
The traditional water supply management approach focuses on (perceived) community requirements that must be met, but not on community demands, which are variable. Therefore a paradigm-shift is required to the way water is considered. In this paper the impact of two distinct approaches for managing the urban water demand, thus daily water consumption, within residential and office buildings are examined through a futures framework. The two fundamental management measures to influence water demand are: 1) structural and technical measures (via adopting water-saving devices); and 2) socio-political measure (via changing users’ behaviour). Both align well with UK policy drivers and results show each in isolation has similar impacts (i.e. 55% reduction) on domestic water consumption per capita, although the ranges over which user behaviour can operate appears to be far more diverse. Most strikingly, when these measures are considered in combination greater impact (i.e. 80% reduction) could be achieved. Conclusions are drawn as to how far water demand management, through a dual track approach, can go in terms of reducing indoor water consumption of both residential and office users and discusses what else is needed in this respect to help contribute to securing sufficient, sustainable supplies within a ‘liveable’ future.
The national demand for water in the UK is predicted to increase, exacerbated by a growing UK population, and home-grown demands for energy and food. When set against the context of overstretched existing supply sources vulnerable to droughts, particularly in the SE of the UK, the delicate balance of matching minimal demands with resource secure supplies becomes critical. Whilst demands can be decreased through changes in user behaviour and adoption of technological efficiency and supplies can be supplemented with additional local sources (e.g. rainwater harvesting – RWH and greywater – GW), careful consideration of future water use performance, particularly in increasingly dense city centres needs to be considered. For this purpose indicators and benchmarks are particularly useful, although any system, once adopted, must be robust and fully understood in terms of its sensitivity to future changes. This paper presents a new benchmarking system for measuring the water using performance of domestic dwellings and considers the impact(s) therein when making changes to ‘internal’ demands either through technological efficiency or user behaviour alone. The sensitivity of water performance is then tested further when combining these changes with additional localised supplies (i.e. RWH and GW) and ‘external’ gardening demands. Therein the impacts (in isolation and combination) of the following are considered: occupancy rates (1 to 4); roof size (12.5 m<sup>2</sup> to 100m<sup>2</sup>); garden size (25 m<sup>2</sup> to 100m<sup>2</sup>); geographical location (NW, Midlands, SE) and yearly temporal effects. Lessons learnt from analysis of the proposed benchmarking system are made throughout this paper, in particular its compatibility with the existing code for sustainable homes accreditation system. Conclusions are subsequently drawn for the robustness of the proposed system.
Projecting the UK’s Future Electricity Supply Mix: A Tool for Generating Sustainable Future Energy ScenariosPublished: 31 October 2013 by MDPI AG in The 3rd World Sustainability Forum
Growing energy demands and climatic changes, exacerbated through rapid increases in CO<sub>2</sub> emissions, are two major global issues facing nations. Therefore ongoing research is being conducted on projecting supply / demand scenarios that look to match future energy demands against energy supply mixes. This requires energy providers to foresee the impact of various electricity generation scenarios on CO<sub>2</sub> emissions and to assess the sustainability of, and risks involved with each so that an attitude of energy provision ‘whatever the cost’ does not prevail decision-making in the face of a plethora of electricity supply mixes and/or energy demand predictions is a complicated procedure which requires in depth consideration of the various scenarios that are being developed. This requires a high level of knowledge that is available only within a team of experts. Furthermore forecasting the possible impacts of various electricity scenarios on climate change as well as considering the associated cost just adds more complexity. This paper explores the features and choices available to decision-makers through the development of an Excel-based tool. The tool acts as a database for existing energy supply/demand scenarios and allows the user to look up existing scenarios or mix and match existing scenarios for the UK leading to a range of new possibilities. The benefits of creating and using the developed tool are explored within the paper and it is concluded that the tool begins to address the complex issues of projecting the most appropriate electricity supply mix and electricity demand by using a range of existing energy studies. In so doing it facilitates greatly decision-makers in beginning the process of further assessing the risks that might be involved. An example of using tool for developing three very different supply mix scenarios for the UK (including one with high share of interconnections) is provided.
The water industry is becoming increasingly aware of the risks associated with urban supplies not meeting demands by 2050. Greywater (GW) recycling for non-potable uses (e.g., urinal and toilet flushing) provides an urban water management strategy to help alleviate this risk by reducing main water demands. This paper proposes an innovative cross connected system that collects GW from residential buildings and recycles it for toilet/urinal flushing in both residential and office buildings. The capital cost (CAPEX), operational cost (OPEX) and water saving potential are calculated for individual and shared residential and office buildings in an urban mixed-use regeneration area in the UK, assuming two different treatment processes; a membrane bioreactor (MBR) and a vertical flow constructed wetland (VFCW). The Net Present Value (NPV) method was used to compare the financial performance of each considered scenario, from where it was found that a shared GW recycling system (MBR) was the most economically viable option. The sensitivity of this financial model was assessed, considering four parameters (i.e., water supply and sewerage charges, discount rate(s), service life and improved technological efficiency, e.g., low flush toilets, low shower heads, etc.), from where it was found that shared GW systems performed best in the long-term.
Future scenarios provide challenging, plausible and relevant stories about how the future could unfold. Urban Futures (UF) research has identified a substantial set (>450) of seemingly disparate scenarios published over the period 1997–2011 and within this research, a sub-set of >160 scenarios has been identified (and categorized) based on their narratives according to the structure first proposed by the Global Scenario Group (GSG) in 1997; three world types (Business as Usual, Barbarization, and Great Transitions) and six scenarios, two for each world type (Policy Reform—PR, Market Forces—MF, Breakdown—B, Fortress World—FW, Eco-Communalism—EC and New Sustainability Paradigm—NSP). It is suggested that four of these scenario archetypes (MF, PR, NSP and FW) are sufficiently distinct to facilitate active stakeholder engagement in futures thinking. Moreover they are accompanied by a well-established, internally consistent set of narratives that provide a deeper understanding of the key fundamental drivers (e.g., STEEP—Social, Technological, Economic, Environmental and Political) that could bring about realistic world changes through a push or a pull effect. This is testament to the original concept of the GSG scenarios and their development and refinement over a 16 year period.
Assessing the sustainability of underground space usage — A toolkit for testing possible urban futuresPublished: 31 March 2011 by Springer Nature in Journal of Mountain Science
A description of the future as it might be without forecasts, predictions and trend analysis can be referred to as a ‘sfuture scenario’. An abundance of scenarios literature exists in which numerous pictures have been painted of changed future worlds. However, upon closer inspection it becomes apparent that virtually all of this literature refers to changes occurring above ground, ignoring the inevitable consequences (or opportunities) for sustainable use of underground space, not least in densely populated urban areas, some of which may be underlain by complex geological conditions. This paper reports on the development (to date) of an ‘Urban Futures’ (UF) toolkit for sub-surface environments (including infrastructure and utilities) which, through use of ‘key’ questions ‘sustainable’ indicators and a ‘contextual’ narrative, allows for better definition and measured performance of underground space in the UK, both today and in the future. The toolkit explores possible uses for underground space within 4 plausible and well-cited future scenarios (i.e. New Sustainability Paradigm, Fortress World, Market Forces and Policy Reform). This forms part of a much larger generic toolkit which the UF research team are developing for exploring possible future scenarios over a range of UK urban regeneration case study areas.
Numerical simulation of the creation and performance of extruded concrete linings in microtunnellingPublished: 01 December 2010 by Elsevier BV in Tunnelling and Underground Space Technology
Electrokinetic (EK) dewatering involves the application of a (direct current) voltage across sewage sludge, driving water under an electrical gradient from the positive electrode (anode) to the negative electrode (cathode). Researchers have shown the technique to be efficient means of driving off water from the sludge, thus improving strength and reducing volume. This paper presents an integrating framework for EK dewatering under constant voltage and constant current conditions, founded on the mathematics of simple electrical circuits and demonstrated by laboratory experimentation. The derived equations and experimental results showed that electroosmotic flow rate decreases with time when dewatering with constant voltage and is constant when constant current conditions are maintained. Having a linear relationship between flow and time, EK dewatering with constant current not only enhances the sludge dewatering efficiency, but also has the advantage of simplifying design procedures.
Environmental geotechnics (EG) has the potential to make a substantial contribution to the field of sustainable construction, which in turn affects sustainable development. Indicators for measuring sustainable performance within the construction sector are well developed because the concepts have been around for many years. However, within the EG sector they are not, probably due to the combined difficulties of inherent site-specific complexity and scale. In addressing this shortfall, the aim of this paper is to present a new suite of environmental geotechnics indicators (EGIs). The new EGI system is formulated from existing construction sector indicators, from which a set of 108 separate indicators for assessing progress towards achieving greater sustainability are presented. Using a point score system (1 (harmful) to 5 (significantly improved)), the set of indicators can cover the entire timeline of a project in eight distinct stages (feasibility to long term). The set includes 76 ‘generic indicators‘ used to assess the sustainability of any geotechnical project and a set of 32 additional ‘technology-specific‘ indicators used to assess the sustainability of specific techniques for treating contaminated land. This latter indicator set can be modified, or substituted by any appropriate technology-specific indicator set, to address whatever geotechnical processes are proposed in a project. The final output of the assessment is an eight-pointed rose diagram that can be used to highlight areas of weakness within a project. The indicators within this new model are not split into various sustainability pillars (economic, social and environmental), thereby reducing the risk of an end-user focusing on the economic pillar alone. The indicators are applied to a case study site.
Eastside, a 130 ha brownfield site located to the eastern side of Birmingham's city centre, is undergoing social, economic and environmental changes, driven mainly through public and private investment estimated to be worth £6 billion. The regeneration programme is well under way and it aims to turn a once deprived inner-city area into the regions first ‘sustainability quarter’ Achieving a sustainable quarter, in terms of energy, will require reductions to be made in energy demands compared to typical practice, for example through more thermally efficient buildings and utilisation of low-energy technologies. In addition it will require these demands to be met through renewable technologies rather than fossil fuels. This paper presents estimates for the total energy demands from the various developments planned within Eastside assuming typical and good-practice scenarios. The paper then assesses the feasibility of introducing various renewable energy supply technologies and combined heat and power (CHP) technologies in order to meet these demands. Finally the paper presents a simplified costing scheme for assessing the potential of renewable technologies to secure energy supplies while limiting carbon emissions. The renewable technologies are compared directly, aiming at providing an independent viewpoint for decision makers when considering which technologies to adopt. While the study focuses on Eastside, the lessons learned from this study are vitally important for redevelopment programmes being undertaken elsewhere.
The £6 billion regeneration of the area immediately to the east of Birmingham's city centre is currently one of the largest redevelopment schemes being undertaken in the UK. The ten-year redevelopment of this 130 ha site is based upon a vision of Eastside as a sustainable exemplar of city centre regeneration. Turning this vision into reality requires both a sustainable policy to be embraced willingly, rather than reluctantly, and best practice to be adopted. This paper describes sustainable options that are essential to a good quality of life (i.e. supply of water and energy) and yet that will help Eastside on the road towards exemplary status. Some of these options are relatively well understood and practically proven (e.g. greywater recycling, rainfall harvesting, borehole abstraction and combined heat and power systems), and indeed have been adopted elsewhere in the UK, while others are closer to ‘blue skies’ concepts (e.g. fuel cells and multi-utility tunnels) and will require step changes in both attitudes and technology prior to their introduction. When assessing the feasibility of implementing these sustainable technologies within a commercial redevelopment scheme there are necessarily many barriers to be overcome. This paper highlights these barriers, some of which are specific to Eastside while others are generic to any redevelopment scheme, and aims to show how many subtle and complex arguments are involved in overcoming them. In so doing, it recommends enablers that should be considered for adoption.
Dexter Hunt participated at conference The 5th World Sustainability Forum.