Sustainable Drainage Systems Research Articles

The potential to retrofit sustainable drainage systems to address combined sewer overflow discharges in the Thames Tideway catchment

AbstractExperience of retrofitting sustainable drainage systems (SuDS) in the United Kingdom is limited, and there are no well‐established procedures for evaluating the feasibility, value or cost‐effectiveness of doing this, particularly at the catchment scale. This paper demonstrates a two‐phase process for evaluating the potential to retrofit SuDS to address combined sewer discharges in three subcatchments within the Thames Tideway catchment of London. The first phase evaluates what might be achieved with various levels of disconnection (‘global’ disconnection scenarios) using hydraulic models, while the second phase considers how disconnection might practically be achieved. High levels of disconnection are technically possible but practicably difficult. In selected cases, and with aggressive implementation of SuDS, combined sewer overflow CSO discharges could potentially be eliminated or reduced to acceptable levels without the need for any modifications to underground assets. However, retrofit SuDS could not eliminate the requirement for some form of sewer modification in any subcatchments.

A proposed decision‐making framework for a national infiltration SuDS map

PurposeThe purpose of this paper is to describe the decision‐making framework and datasets behind a national geographical information system (GIS) map that assesses the suitability of the subsurface for infiltration sustainable drainage systems (SuDS). In combination they provide geoenvironmental information on the necessary geological and hydrogeological considerations to facilitate preliminary site assessment.Design/methodology/approachThe national suitability map comprises four parts, each of which considers a geoenvironmental factor essential to SuDS planning, installation and performance. The first three comprise: drainage; ground stability; and pollutant attenuation potential. The final map highlights those areas where infiltration may result in negative consequences such as the initiation or exacerbation of flooding or ground instability.FindingsThe application of the suitability map is demonstrated for an urban setting, showing its relevance to both planning for wide spatial‐assessment and site‐scale assessment.Research limitations/implicationsThe suitability map aims to provide the data necessary for the assessment of subsurface suitability, rather than a recommendation on the type of infiltration system appropriate to the ground conditions. Future research could address this limitation by incorporating the use of quantitative site‐scale information, although it is unlikely that this would be possible at a national scale.Practical implicationsThe suitability map is valid for use by developers and planners for the preliminary assessment of sites, but also by unitary authorities for the consideration of planning applications.Originality/valueThe paper introduces an innovative decision‐making framework to enable preliminary site assessment for infiltration SuDS and demonstrates the feasibility of the approach through an urban case study.

Research finds that kitchen and garden waste could be ideal for making Suds

New research has shown that large volumes of garden and kitchen waste collected from homes could be beneficially re-used in sustainable drainage systems rather than sent to landfill. Sue Charlesworth of Coventry University reports.

‘New Water Architecture’: an integrated water management model

An integrated framework for the management of water in England and Wales is proposed that optimises the organisation of service infrastructure, customers and stakeholders to derive optimal social, economic and environmental health. ‘New Water Architecture’ recognises the intrinsic links between water stakeholders, and between water and other essential resources, particularly food, energy and biodiversity. A systems-based approach strengthens integration of physical infrastructure, controlling institutions, and the overarching society consensus. Consideration is also given to future pressures with resilience to climate change strengthened by initiatives that slow water passage across the landscape. Implementation of the framework requires coordinated water policy across traditionally discrete resource sectors. This need is investigated alongside specific initiatives related to system management, abstraction licensing and pricing. Capital investment should be targeted towards ‘low-regret’ infrastructure argued to be high flow storage, aquifer storage and recovery, sustainable drainage systems and water transfers. These examples deliver multiple benefits and can be further optimised if existing networks, particularly inland waterways, are revitalised to enable regional integration of water sources.

A GIS-based methodology for selecting stormwater disconnection opportunities

The purpose of this paper is to introduce a geographic information system (GIS)-based decision support tool that assists the user to select not only areas where (retrofit) sustainable drainage systems (SuDS) could be implemented within a large catchment (>100 ha), but also to allow discrimination between suitable SuDS techniques based on their likely feasibility and effectiveness. The tool is applied to a case study catchment within London, UK, with the aim of increasing receiving water quality by reducing combined sewer overflow (CSO) spill frequency and volume. The key benefit of the tool presented is to allow rapid assessment of the retrofit SuDS potential of large catchments. It is not intended to replace detailed site investigations, but may help to direct attention to sites that have the greatest potential for retrofit SuDS implementation. Preliminary InfoWorks CS modelling of 'global disconnections' within the case study catchment, e.g. the removal of 50% of the total impervious area, showed that CSO spill volume could be reduced by 55 to 78% during a typical year. Using the disconnection hierarchy developed by the authors, the feasibility of retrofit SuDS deployment within the case study catchment is assessed, and the implications discussed.

A planning framework for sustainable urban drainage systems

Sustainable urban drainage systems (SUDS) call for collaborative and interdisciplinary practices. The problem with this is the social and technical complexities involved, and the absence of a shared understanding of the challenge and the scope of integrated solutions. It is necessary to clarify the contributions and interactions between disciplines in order to achieve integrated planning and design of SUDS. This paper reviews the literature across disciplinary fields and outlines key messages and uncertainties within each discipline. The outcome is a framework comprising time, space and human values, as well as biophysical processes (e.g. engineering), spatial strategies (e.g. urban design) and adaptive strategies (e.g. management). It identifies the planning of SUDS as a collective learning process with continuous iterations between disciplines, while also reflecting the past, present and future of a specific site.

Decision support for sustainable urban drainage system management: A case study of Jijel, Algeria

This paper aims to develop a methodology to support the sustainable management of Urban Drainage Systems (UDSs) in Algeria. This research is motivated by the various difficulties that the National Sanitation Office (ONA) has in managing this complex infrastructure. The method mainly consists of two approaches: the top-down approach and the bottom-up approach. The former facilitates the identification of factors related to a sustainable UDS, the development priorities and the criteria available to managers. The latter assesses UDS performance using the weighted sum method to aggregate indicators or criteria weighted using the Analytical Hierarchy Process (AHP). The method is demonstrated through its application to the UDS in the city of Jijel, Algeria.

Selecting SUDS in the Valencia Region of Spain

This paper reports on a study of the implementation of sustainable urban drainage systems (SUDS) in two Spanish towns (Xàtiva and Benaguasil) as part of the EU LIFE+ Project AQUAVAL, which has been conceived to introduce examples of sustainable drainage to the Valencia Region of Spain. Six sites in a range of common urban spaces and land uses are selected and appropriate SUDS techniques proposed by means of a decision-support process. This primarily consisted of the systematic application of key selection criteria through matrices and scores, followed by a brief sustainability analysis. Stakeholders' preferences and opinions as well as educational and social opportunities are highly considered throughout the process. General monitoring requirements and major limitations in using the methodology are outlined, stressing the need for improvement of four main aspects: local data regarding SUDS performance, detail of the sustainability analysis, support through comprehensive modelling tools, and level of stakeholder engagement. The importance of creating showcases for SUDS in Mediterranean Regions, thus adapting key selection criteria as to foster sustainable drainage understanding and expertise is highlighted.

Assessing the combined benefits of water recycling technologies by modelling the total urban water cycle

This study investigates the potential benefits of new technologies, modern appliances, and innovative techniques that help to improve the performance of the urban water cycle. Urbanisation is a major source of additional pressures (both qualitative and quantitative) on the environment. For example abstractions to cover the increased demands for water supply or alterations of the topographic and geomorphologic properties of the land cover result in considerable changes to the dynamics of the hydrosystem (change of average and maximum values of flows). Sustainable, water-aware technologies, like SUstainable Drainage Systems (SUDS) and rainwater harvesting schemes, can be implemented to reduce these adverse effects. These technologies introduce interactions between the components of the urban water cycle. Rainwater harvesting for example, apart from the potable water demand reduction, may have a significant influence on the generated runoff. Consequently, an integrated modelling of the urban water cycle is necessary for the simulation of the water-aware technologies and the identification of their combined benefits. In this study, two hypothetical developments implement rainwater harvesting schemes and SUDS and are simulated using the Urban Water Optioneering Tool (UWOT), which is capable of using rainfall time series of arbitrary time steps. The two hypothetical developments were studied to investigate the contribution of the water-aware technologies to the minimisation of the environmental pressures. Significantly different urban density was assigned to these developments to highlight the influence of urban density on the efficiency and reliability of the water-aware technologies. The results indicate that: (a) water-saving schemes like rainwater harvesting and greywater treatment can reduce significantly the pressures of new developments (e.g., reduction of potable water demand by 27%); (b) the reliability of the water-aware technologies decreases with urban density; and (c) if localised rainwater harvesting is implemented then the efficiency of the water appliances influences considerably the generated runoff.

Building the evidence base for ecological impact assessment and mitigation

Building the evidence base for ecological impact assessment and mitigation

An impact assessment methodology for urban surface runoff quality following best practice treatment

The paper develops an easy to apply desk-based semi-quantitative approach for the assessment of residual receiving water quality risks associated with urban surface runoff following its conveyance through best practice sustainable drainage systems (SUDS). The innovative procedure utilises an integrated geographical information system (GIS)-based pollution index approach based on surface area impermeability, runoff concentrations/loadings and individual SUDS treatment performance potential to evaluate the level of risk mitigation achievable by SUDS drainage infrastructure. The residual impact is assessed through comparison of the determined pollution index with regulatory receiving water quality standards and objectives. The methodology provides an original theoretically based procedure which complements the current acute risk assessment approaches being widely applied within pluvial flood risk management.

Analyzing the first loop design process for large-scale sustainable urban drainage system retrofits in Copenhagen, Denmark

Sustainable urban drainage systems (SUDS) receive much attention as a means to adapt urban environments to a changing climate. Yet little knowledge exists on how to adapt existing urban drainage systems by use of SUDS at the scale of entire sewer-sheds. This paper aims to assist landscape architects, engineers, and planners in the design of large-scale SUDS retrofits. It analyzes the first loop in an exemplary design process for SUDS retrofits in a 15 km2 case-study area in Copenhagen, Denmark. A series of ‘insights’ and ‘set backs’ are revealed in the process and discussed in their importance for a successful design. The two most important aspects are identified as the need to develop context specific solutions and the utilization of underlying hydrological conditions as generator of urban form.

A LCC Analysis of Rainwater Management Variants

A LCC Analysis of Rainwater Management VariantsThe paper presents results of the Life Cycle Cost (LCC) analysis carried out for several variants of rainfall water management in a newly designed multi-family dwelling house. According to the LCC methodology, calculations were performed for the whole undertaking life cycle with both investment outlays and operation/maintenance costs taken into account. The LCC analysis was carried out, in particular, for a variant assuming that the rainwater collected from the roof will be entirely discharged to the sewage system. On the other hand, the second variant provided for replacement of traditional building roof with a green one. Facilities of that type, thanks to their retention properties, may delay runoff of rainwater and reduce the overall quantity of water discharged from roof surface and therefore can be classified as Sustainable Urban Drainage Systems. In the third case considered, rainwater is to be utilised in the building. It was assumed that precipitation water will be stored in a tank and used in the sanitary water supply system for flushing toilets, thus reducing the overall tap water purchase costs.

Investigation of Nanoparticle Transport Inside Coarse-Grained Geological Media Using Magnetic Resonance Imaging

Quantifying nanoparticle (NP) transport inside saturated porous geological media is imperative for understanding their fate in a range of natural and engineered water systems. While most studies focus upon finer grained systems representative of soils and aquifers, very few examine coarse-grained systems representative of riverbeds and gravel based sustainable urban drainage systems. In this study, we investigated the potential of magnetic resonance imaging (MRI) to image transport behaviors of nanoparticles (NPs) through a saturated coarse-grained system. MRI successfully imaged the transport of superparamagnetic NPs, inside a porous column composed of quartz gravel using T(2)-weighted images. A calibration protocol was then used to convert T(2)-weighted images into spatially resolved quantitative concentration maps of NPs at different time intervals. Averaged concentration profiles of NPs clearly illustrates that transport of a positively charged amine-functionalized NP within the column was slower compared to that of a negatively charged carboxyl-functionalized NP, due to electrostatic attraction between positively charged NP and negatively charged quartz grains. Concentration profiles of NPs were then compared with those of a convection-dispersion model to estimate coefficients of dispersivity and retardation. For the amine functionalized NPs (which exhibited inhibited transport), a better model fit was obtained when permanent attachment (deposition) was incorporated into the model as opposed to nonpermanent attachment (retardation). This technology can be used to further explore transport processes of NPs inside coarse-grained porous media, either by using the wide range of commercially available (super)paramagnetically tagged NPs or by using custom-made tagged NPs.

Design and construction of an experimental pervious paved parking area to harvest reusable rainwater

Pervious pavements are sustainable urban drainage systems already known as rainwater infiltration techniques which reduce runoff formation and diffuse pollution in cities. The present research is focused on the design and construction of an experimental parking area, composed of 45 pervious pavement parking bays. Every pervious pavement was experimentally designed to store rainwater and measure the levels of the stored water and its quality over time. Six different pervious surfaces are combined with four different geotextiles in order to test which materials respond better to the good quality of rainwater storage over time and under the specific weather conditions of the north of Spain. The aim of this research was to obtain a good performance of pervious pavements that offered simultaneously a positive urban service and helped to harvest rainwater with a good quality to be used for non potable demands.

Urban drainage in Ireland – embracing sustainable systems

AbstractThe current approach to stormwater management in Ireland requires that outflows from new developments are restricted to greenfield values that would have occurred prior to development. This typically involved the use of holding tanks constructed within developments to attenuate stormwater from where it was released at a reduced rate via a control structure to a nearby drainage network or watercourse. Improved drainage policies now require that sustainable drainage systems (SuDS) are used to meet this objective. This study presents an evaluation of perceived issues that may impede the adoption of new policies. The findings are based on surveys and focus groups of practitioners involved with the planning and design of drainage systems. Although the study indicates that benefits of SuDS are reasonably well understood, their use, for many reasons, has remained less popular. Concerns with ongoing maintenance and long‐term responsibility of SuDS remain impediments to the embracing of these systems in drainage strategies.

Lagos (Nigeria) flooding and influence of urban planning

The aim of the study was to analyse the causes of the flooding problems being encountered in Lagos (Nigeria) and to recommend sustainable management solutions to them. Data on climate, drainage infrastructures and physical planning regulations were collected and extensively analysed. These were combined with evidence from field inspection and discussion with stakeholders, including relevant government departments, university researchers and selected residents. The investigation revealed that, contrary to popular wisdom, climate change or unusually high rainfall is not the primary cause of the flooding problems in Lagos. Rather, the increased urbanisation, lax planning laws in relation to the erection of buildings in flood plains and the lack or inadequacy of storm drainage facilities in the city are to blame. It is argued that a lasting solution to the flooding problem will require the incorporation of sustainable drainage systems within the existing flood management strategy for the city and planning for this must start now.

Performance of Permeable Asphalt Pavement during Rainfall Infiltration

The purpose of this paper is to summarize the performance of permeable asphalt pavements (PAP) and to recommend future areas of research and development. The development of PAP as an integral part of sustainable drainage systems is reviewed in the context of traditional and modern urban drainage. The difference between the permeable asphalt pavement and the ordinary bituminous concrete pavement is discussed. A description of the seepage calculation model based on the structural characteristics of PAP is presented. And also water level fluctuations of both the water permeable asphalt pavement and the ordinary bituminous concrete pavement are analyzed by comparing their numerical simulation results. Finally the drainage performance of the water permeable asphalt pavement is demonstrated. The long-term effectiveness of permeable pavement as an alternative to traditional impervious asphalt pavement is examined. The simulation results could provide significant guidance for the structure design of water permeable asphalt pavement.

Stakeholder Management for Sustainable Development Implementation: The Case of a Sustainable Urban Drainage System

Sustainable development has been widely supported as the concept upon which the future, if we are to have one, must be founded. As such and simplistically, it has often been expected that changes in behaviour at the local level would become evident as sustainable development becomes more entrenched in thinking and practice. Unfortunately, a failure to detect the occurrence of such changes gives rise to the notion that the concept of sustainable development is substantially problematic to translate from thought into action. This has led to greater attention on the procedures of sustainable development implementation (Lafferty and Langhelle, 1999b) and to its examination using new lenses for consideration and enquiry (Gladwin et al., 1995).This paper uses stakeholder thinking to analyse a case study of a local-level implementation of sustainable development, in the form of a sustainable urban drainage system in Sheffield, England. The paper utilises stakeholder thinking to examine the roles of stakeholders in the case in order to analyse the distribution of the impacts of the implementation and by doing so to better understand the process of implementation.The paper demonstrates the complexity of stakeholder relationships, interactions and processes of engagement (Georgakopoulos and Thomson, 2008) in that, although the analysis suggests the implementation to represent an ‘all stakeholder win’, it also highlights that each stakeholder has the power to both impede and facilitate the process. A confused ‘collective responsibility’ situation between stakeholders is identified, judged to lack real accountability and to be creating inertia. From these findings the paper gives consideration to alterations to create real world change towards more favourable conditions for sustainable development implementation.

Storm-Water Management through Infiltration Trenches

With urbanization, the permeable soil surface area through which recharge by infiltration can occur is reducing. This is resulting in much less ground-water recharge and greatly increased surface run-off. Infiltration devices, which redirect run-off waters from the surface to the sub-surface environments, are commonly adopted to mitigate the negative hydrologic effects associated with urbanization. An infiltration trench alone or in combination with other storm water management practice is a key element in present day sustainable urban drainage systems. A solution for the infiltration rate from an infiltration trench and, consequently, the time required to empty the trench is presented. The solution is in the form of integrals of complicated functions and requires numerical computation. The solution is useful in quantifying infiltration rate and/or artificial recharge of ground-water through infiltration trenches and the drain time of the trench, which is a key parameter in operation of storm water manage...