Impact case study database

The average annual cost of flooding in the UK is £1.3 billion, rising to £1.6 billion in relation to the winter 2016/2017 floods. Part of the UK’s response to tackling urban flooding on this scale was the adoption of the Flood and Water Management Act (2010) requiring the use of SuDS in all new and re-developments. When the Act’s requirement proved unenforceable in England, our research contributed to the development of National Best Practice guidelines (The SuDS manual; CIRIA, 2015) to support consistent interpretation and implementation of this requirement (5-1). For example, our research directly informs the chapters on water quality (Chapter 26) and health and safety (Chapter 36). These National Best Practice guidelines are used by all 343 Local Authorities in England and surface water management practitioners (covering a population of 55.9 million). Specifically, our papers on designing SuDS to address water quality and the use of risk-benefit analysis to support the assessment of risks to public health and safety underpins the water quality and risk assessment approaches in the revised manual, respectively. Our research also contributed to the Welsh Statutory SuDS standards relating to water quality enhancement (5-2): “ In developing these standards, we drew directly on the research findings of Middlesex University in relation to Standard S3 – water quality. This part of the standards adopts a simplified version of approach set out in Ellis et al., 2012..” (Welsh Government Water Policy Lead 5-2).

Our research is currently informing policy development in two key areas: the mitigation of diffuse urban pollution using SuDS/BGI and its use within urban planning. In this REF period, our SuDS/BGI work has informed the thinking of environmental regulators and practitioners throughout the UK (5.1, 5.2, 5.3, 5.4). As practitioner-demand for knowledge shifted from understanding to managing the issue (evidenced by the award of EU, Research Council, EA and industry funding of >£2.2million), our research on diffuse pollution mitigation using SuDS/BGI has underpinned the role of SuDS as water quality measures. It continues to inform policy e.g. the Greater London Authority, Transport for London and the Environment Agency released a joint statement promoting our road pollutant hot spot screening tool as best practice in identifying locations for the introduction of road-side SuDS/BGI within London (5-3): “This study will help us to work out where both we and the other authorities responsible for roads in London could intervene to make runoff cleaner and improve water quality in rivers for everyone” (Transport for London Head of Transport Strategy and Planning, 5-3). Our research into using SuDS/BGI to manage urban stormwater above ground – in contrast to the traditional piped approach - is fully embedded within the ISO Guidelines for Stormwater Management in Urban Areas (2020), also adopted as BSI DIS 20325 in the UK): “In my role as chair of the BSI committee, I used their research in the development of the ISO Guidelines for Stormwater Management (2020). Specifically, their research on pollution control using SuDS contributed to the inclusion of blue-green infrastructure as an evidence-based approach for mitigation urban stormwater within the guidelines”; (5-4; Brian Smith Yorkshire Water Head of Drainage Strategy (2013-2019) and current BSI Committee Chair).

With regard to urban planning, our novel work integrating lay perspectives within development of SuDS/BGI zones and identifying opportunities for its integration within planning processes has led to the approach being adopted within urban planning legislation of three municipalities within the metropolitan Area of Belo Horizonte (BH), Brazil (5.5). Our input ensured that the role of SuDS/BGI in contributing to the delivery of human health and wellbeing objectives (including environmental justice) is identified in Belo Horizonte planning policy and the inclusion of blue-green spaces must be considered in all new developments. In relation to societal impact at a national level “ the work of Middlesex University – via their contribution to the Welsh SuDS Standards – directly contributes to more and better outcomes in enhancing surface water quality in Wales. This approach to diffuse pollution mitigation would have not been possible without your work on diffuse pollution, providing a better understanding of the sources and types of diffuse water pollution and of the pollutant removal processes which underpin the design and operation of SuDS” (5-2 –a; Welsh Government Water Policy Lead 2008-2018; 5-2-a).

Whilst the discreet economic impact of our research is impossible to quantify on a standalone basis, the use of SuDS/BGI is identified as a key way to increase the resilience of urban areas to flooding (causing estimated damages of £1.3 billion per year). Our research has helped to articulate the value of SuDS/BGI in terms of its contribution to diffuse pollution mitigation and supported the recognition and subsequent assessment of SuDS/BGI as providers of multiple ecosystem services. More recently our research has embraced opportunities to contribute to understanding the wider societal benefits provided by SuDS/BGI as part of the delivery of sustainable urban planning (4.5).