Construction of Europe’s first ever ‘smart canal’ scheme has started in Scotland using the 250-year-old Forth & Clyde Canal and 21st century technology to mitigate flood risk as well as enable massive regeneration in Glasgow. This is one of 29 different projects which are being rolled out across Scotland under the umbrella of ‘Scotland’s 8th City – the Smart City’ which is a collaborative innovation across Scotland’s cities of Aberdeen, Dundee, Edinburgh, Glasgow, Inverness, Perth, and Stirling. By working together the seven cities have bought into a vision to make cities more attractive, liveable and resilient through data and digital technology.
Part of the North Glasgow Integrated Water Management System, this “smart” project will help to create a ‘sponge city’ for North Glasgow – passively absorbing, cleaning and using rainfall intelligently and will help manage the impact of climate change on the sewer network.
Advanced warning of heavy rainfall (of which Glasgow has rather alot!!) will automatically trigger a lowering of the canal water level to create capacity for surface water run-off. Before periods of heavy rain, canal water will be moved safely through a network of newly created urban spaces – from sustainable urban drainage ponds to granite channels – that absorb and manage water in a controlled way, creating space for surface water run-off.
This scheme will unlock 110 hectares across the north of the city for investment, regeneration and development and will see the Forth & Clyde Canal connected to five new sites over the next 10-15 years, including Sighthill, Hamiltonhill, Ruchill Hospital, Cowlairs and Dundashill.
“By unlocking the inherent value of Glasgow’s Canal and diversifying how we use this publicly-owned heritage asset, we are ensuring it continues to deliver for local people 250 years after it was first built.
”Creating a dynamic urban canal which uses smart technology to move water safely about the city will not only reduce the flood risk impact of climate change, but act as a catalyst for new investment, jobs, homes and businesses in North Glasgow as well as help to create one of the city’s top tourist destinations.”
Catherine Topley, CEO at Scottish Canals
This infographic, created for Natural Course, can help catchment partners communicate to communities the multiple benefits of Natural Flood Management. Natural Course is an EU funded LIFE Integrated Project, that will run for 10 years to improve and protect the water quality of the North West of England.
Rainwise – Northumbrian Water’s surface water management programme was established to address the goal of reducing the risk of future flooding to 7,200 properties across the North East of England by the end of 2020. It is a proactive approach to flooding – working in collaboration with stakeholders and local communities.
Following the flooding event in June 2012, when Tyneside received over 3-inches of rain in just over an hour, a pilot ‘Tyneside Sustainable Sewerage Study’ was set up – a national first where Northumbrian Water joined forces with other risk management authorities to share information, find benefits and identify projects to construct together to deal with catchment wide flooding mechanisms.
The principles of partnership working were expanded across the North East to create the Northumbria Integrated Drainage Partnership (NIDP). This provides a framework for multiple agencies to look for the best and most sustainable solutions to flooding and allows costs & benefits to be better understood and prioritized on a like-for-like basis.
The partnership projects share common characteristics and themes. They addressed catchment wide flooding and flow management, valuing SuDS and natural systems. All projects include scenarios which no single agency could have addressed alone or without detrimental effects to others. They have all been delivered with capital efficiency to the parties, primarily through jointly sourcing engineering consultants and contractors.
A key message of Rainwise is to raise awareness of SuDS and encourage people to make changes around their home that reduce the amount of water entering the sewer. By taking action communities can collectively affect their own resilience to future flooding. Local communities are involved in the planning stages of projects allowing better information and better solutions, providing context sensitive designs which are right for the business and the community.
Source: Schneeberger, K., Huttenlau, M., Winter, B. et al. (2017). A probabilistic framework for risk analysis of widespread flood events: a proof-of-concept study. Risk Analysis. DOI: 10.1111/risa.12863.
Effective flood-risk management requires accurate risk-analysis models. Conventional analysis approaches, however, are based on the evaluation of spatially homogenous scenarios, which do not account for variation in flooding across a river’s reach and catchment area. Since flood events are often spatially unevenly distributed modelling may be inaccurate and invalid. A novel framework for risk analysis that accounts for varied flood outcomes has been developed, and it successfully demonstrated the accuracy of the approach when it was applied to a proof-of-concept exercise in Vorarlberg, Austria. By facilitating improved prediction and quantification of flood events, this model is likely to inform future flood-risk management and related decision-making.
Floods can significantly impact on the lives and livelihoods of populations in affected regions. For this reason, the European Union Floods Directive stipulates that Member States must design and implement risk-oriented flood-management approaches aimed at minimising the negative consequences of flooding. However, conventional analysis models are limited in their ability to accurately assess and evaluate flood risk in large-scale study areas. Tools that can provide information on possible flood scenarios, including their likelihood and potential consequences, are required to enable effective planning.
One reason that conventional flood-risk analysis approaches are limited is that they are based on the evaluation of spatially homogeneous flood scenarios, whereas flood events tend to be spatially heterogeneous. This is especially true when one is considering large study areas or mountainous regions. To solve this problem, Austrian scientists have developed a new framework for the probabilistic risk analysis of river flooding that accounts for the spatially heterogeneous nature of flood events.
The model is composed of three modules:
- A hazard module (HM) that evaluates potential flood hazard. After analysing observed flood events, it generates a large set of possible future events across the river network and determines flood risk for specific sections of the network.
- An impact module (IM) that characterises the potential negative consequences of flooding. It examines three impact indicators — unit of flood hazard (the number of sites affected by flooding); potential affected buildings; and potential direct monetary building damage — to ascertain the impact on specific areas or communities along the river network.
- A risk-assessment module (RM) that combines and statistically analyses the results of the first two modules to quantify the expected annual flood impact (in terms of expected annual damage) and calculate the probability that various levels of loss will be exceeded.
To demonstrate the applicability of this new framework and its suitability for mid-to-large-scale applications, researchers used the model to quantify flood risk in Vorarlberg, an Austrian province in the Eastern Alps that is vulnerable to flooding. Although flood-risk estimations are generally based on extremes, and so are associated with large uncertainties, for most individual components, the simulated flood risk for Vorarlberg matched well with observed data.
This new approach, which considers flood events as spatially heterogenous, has the potential to improve the prediction and quantification of flood risk in regions of interest, facilitating the more realistic flood-risk estimations required for advanced flood-defence planning. As such, this research is likely to be of interest to stakeholders involved in flood-risk management, including policymakers, risk analysts and insurance providers.
Source: Tapia, C., Abajo, B., Feliu, E., et al. (2017). Profiling urban vulnerabilities to climate change: An indicator-based vulnerability assessment for European cities. Ecological Indicators. 78:142-155. DOI:10.1016/j.ecolind.2017.02.040
This study assessed the vulnerability of 571 European cities to heatwaves, droughts and flooding caused by climate change and results could be used to design policies to mitigate the impacts. With more than 75% of the EU’s population lives in urban areas understanding how cities may be vulnerable to the effects of climate change is, therefore, crucial in planning for the future.
In this study, which was supported by the EU Project RAMSES 1, researchers carried out an indicator-based vulnerability assessment (IBVA) for 571 European cities. The IBVA used a set of indicators to assess urban vulnerabilities to climate stress and their consequences: (i) heatwaves on human health; (ii) drought on water planning, and; (iii) the socio-economic impact of flooding, including fluvial, pluvial and coastal flooding.
IBVAs help to identify factors that lead to vulnerability to climatic hazards. The Intergovernmental Panel on Climate Change (IPCC) definition of vulnerability is “the propensity or pre-disposition to be adversely affected,” 2 by climate change and this also encompasses the lack of capacity to cope with and adapt to the effects of climate change.
Indicators were developed from a review of published literature to identify the climate threats most relevant to European cities and were classified into five broad categories, comprising:
- human capital
- socio-economic conditions
- built environment
- natural and ecosystem services
- governance and institutions
Data for the 571 cities assessed by the IBVA were mostly taken from the Urban Audit database, which has been used previously for other climate-change vulnerability assessments. New indicators based on big data were also produced to assess different aspects related to adaptive capacity such as awareness of the main climate stressors. Coastal-flooding vulnerabilities were assessed for the 92 coastal cities within the database. The fluvial-flooding assessment was completed on the 365 cities with water bodies with a catchment of at least 500 square kilometres.
The researchers grouped the cities into seven different clusters according to their relative degree of vulnerability to each of the three climate stressors.
Cities that showed higher vulnerability to heatwaves were predominantly located in the central areas of the EU and in the southern regions of new Member States and the Baltic republics. This was in part linked to elderly populations, higher pollution levels and small dwelling size, which, in combination, increase the urban sensitivity to heatwaves. Surprisingly, many of the cities with lower vulnerabilities to heatwaves were located in some of the warmest areas of Europe, which is likely due to raised awareness of heatwaves in these regions.
Cities more vulnerable to droughts, such as Brussels, Ludwigshafen am Rhein and Marseille, were found across Europe, without a clear spatial distribution pattern. Overall, higher vulnerabilities are explained by comparatively less diversified economies, growing populations and less efficient water-management systems (i.e. higher resource consumption at greater water costs).
Vulnerabilities were found across Europe, although lower susceptibility was found in the British Isles and Scandinavian countries, compared to high vulnerability scores in the Mediterranean countries, Bohemian and Danubian regions. The factors influencing flooding included socio-economic conditions (e.g. income levels and employment rates), physical features, such as the extent of soil sealing and the awareness of citizens, and the commitment to adaption of the cities’ governing institutions. For coastal flooding, cities over the Atlantic coasts, western Mediterranean and Baltic showed higher vulnerability than the Italian Peninsula, the UK and the Scandinavian countries, which were shown to have a higher capacity to adapt, as well as higher awareness and commitment to addressing coastal flooding.
The study results demonstrate the challenges European cities face due to climate change, with cities across Europe vulnerable to the effects of either floods, heatwaves or droughts. For each city, the causes of vulnerability to the consequences of climate change are dependent on the specific geographical and socioeconomic conditions. The research emphasises the importance of city-level assessments, particularly for cities identified as vulnerable to one or more of hazards in this assessment, in order to inform adaption planning. They also say that the IBVA used here could be developed to include the adaptation measures already established in European cities, in order to understand whether these measures have reduced a city’s vulnerability to potential climate hazards.
Cities comprise a range of social systems, buildings, infrastructure and natural features, which makes planning for the future difficult. The researchers say that the assessment can be used by city planners and can contribute to the development of EU policies to adapt to climate-change. They say the results enable comparison across European cities, because the definitions and indicators are consistent for all the cities assessed. The researchers highlight that vulnerability is most directly linked to social conditions and that tackling these issues could lead to policy interventions that have win-win scenarios for both urban resilience and socioeconomic issues.
- This research received funding from the EU’s Seventh Programme for Research, Technological Development and Demonstration (Project RAMSES).
- IPCC (2014): Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. IPCC, Geneva, Switzerland, Annex II: Glossary.
Source: Pappalardo, V., La Rosa, D., Campisano, A., La Greca, P.(2017). The potential of green infrastructure application in urban runoff control for land use planning: A preliminary evaluation from a southern Italy case study. Ecosystem Services. 26(B): 345–354. DOI: 10.1016/j.ecoser.2017.04.015.
This study investigates how green roofs and permeable paving contribute to flood mitigation. Using a hydraulic model technique, the research found that, in particular urban cases, green roofs were more effective than permeable paving. Policies to promote the adoption of sustainable urban drainage systems (SUDS) could prove more effective under certain circumstances, and policymakers should look at ways to promote SUDS where suitable.
A worldwide trend in an increase in impervious surfaces (impermeable to water), coupled with precipitation extremes, are contributing to a rise in urban flooding. Current drainage systems may struggle to cope with the amount of water run-off during heavy rainfall events, which are predicted to increase under climate change1. The effectiveness of green roofs and permeable paving for stormwater management in an urban location was assessed.
SUDS refers to a range of drainage technologies that are more sustainable than conventional solutions2, and may include types of green infrastructure, for example green roofs, permeable surfaces, and purpose-built ponds and wetlands. These techniques use landscape features and natural processes to slow flows of water, increase evaporation and encourage infiltration into the ground. As a co-benefit, SUDS strategies can enhance ecosystem services, such as wildlife habitat, carbon sequestration, recreation and education. Conventional drainage, meanwhile, focuses on channelling water into drainage areas as quickly as possible.
To evaluate the effectiveness of two types of SUDS, the researchers compared three scenarios in the city of Avola, Sicily — an area which underwent rapid urbanisation in the 20th century. First, they identified the amount of land falling into different use categories, for example ‘residential-semi-intensive’, with less than 50% permeability, ‘road and parking areas’ and ‘bare soil’, and obtained plans of the sewer system. Together with rainfall data going back to 1940, these inputs were used with modelling software (the US EPA Storm Water Management Model3) to analyse water flows and run-off under each scenario, for a sub-catchment (part of the wider watershed) in the city.
Modelling was conducted over two-, five- and 10-year timeframes, taking into account the number of peak-flow events (e.g. storms) that would be likely to occur during this time, known as a ‘return period’. In the first scenario, with no SUDS measures in place, modelling showed that the existing drainage system would not cope adequately with peak flows over five and 10 years — therefore flooding would occur in several places.
In the second scenario, 150 areas of permeable paving, covering 15 m2 each, replaced impermeable surfaces in public spaces. In the final scenario, green roofs were installed on 110 buildings, covering about 3.3 hectares. These measures were placed upstream of the area that experienced flooding in the non-SUDS scenario.
Results showed that green roofs were the most effective at mitigating run-off and flooding, but efficacy depended on the return period considered. Over two-year periods, both permeable paving and green roofs exhibited improvements over the first scenario, and over five years they reduced, but did not prevent, flooding. Green roofs halved the volume of flooding over the 10-year period, while permeable paving only slightly reduced the incidence.
Surface run-off, meanwhile, was reduced from 34.7mm (non-SUDS) to 34.3mm (permeable paving) and 30.7mm (green roofs), in this time period, indicating limited benefits in this category.
The researchers attribute such limited benefits to the small area covered by the SUDS measures and the fact that the area was limited to public space, compared to the large impervious surface area over the whole catchment. They also acknowledge that the SUDS modelled were only designed to achieve a general reduction in run-off peak discharge, to relieve downstream areas during heavy precipitation.
The results are also subject to some uncertainty. There is a lack of field data on the performance of real-life SUDS in southern Europe and the Mediterranean region, but such data would help to improve modelled results. Such validation would also allow urban planners to use this type of model to inform the best positioning of SUDS, say the researchers. The researchers also underline that results obtained from SUDS simulations are strongly dependent on site-specific characteristics of the urban catchment, which limit the possible location of permeable pavements and, therefore, favour green roofs. In this study, the researchers highlight that more substantial mitigation of peak flow was achieved by green roofs, which are located on private buildings, than permeable paving in public areas. This implies that policies incentivising private adoption of SUDS measures are important. Demonstration projects and subsidies may be used to drive adoption, they suggest, as well as compliance-based instruments such as building-code requirements.
1. Fratini, C. F., et al. (2012). Three Points Approach (3PA) for urban flood risk management: A tool to support climate change adaptation through transdisciplinarity and multifunctionality. Urban Water Journal, 9(5): 317–331.
2. Fletcher, T.D., Shuster, W., Hunt, W.F., et al. (2014). SUDS, LIDS, BMs, WUDS and more – The evolution and application of terminology surrounding urban drainage. Urban Water Journal, 12(7): 525–542
3. Rossman, L.A., 2010. Storm Water Management Model User’s Manual. Version 5.0.
For technical information, guidance and advice, CIRIA provides a comprehensive range of resources on SuDS through its Susdrain network. It has also produced detailed best practice guidance on the planning, design, construction and maintenance of SuDS in ‘The SuDS Manual’ and an accompanying ‘Site handbook for the construction of SuDS’, which provides guidance on the construction of SuDS to facilitate their effective delivery.
The Landscape Institute’s Technical Committee published Management and Maintenance of Sustainable Drainage Systems (SuDS) Landscapes (March 2014) which includes a selection of water management case studies.
Department for Environment, Food & Rural Affairs and The Rt Hon Michael Gove MP published their ‘A Green Future: Our 25 Year Plan to Improve the Environment’ which sets out what the government will do to improve the environment. The plan seeks to deliver an end to plastic waste, create new habitats for endangered species, a ‘green Brexit’, create nature-friendly schools, and lead the way for other countries to tackle environmental destruction. The 25-year plan also confirmed that the government will consult on plans for the development of a statutory body – a “world-leading” and independent environmental watchdog – to ensure standards on clean air, water and soil will be maintained post-Brexit.
The government has pledged to expand the use of natural flood management solutions, put in place more sustainable drainage systems and make at risk properties more resilient to flooding. Although £15M has been set aside for natural flood management up to 2021 in the 2016 budget but no further flood investment was announced in this report. Sustainable drainage systems (SuDS) such as permeable surfaces, storage tanks and ponds, to reduce the risk of surface water flooding will be encouraged and the government said it would consider changes to the national planning policy framework and building regulations.
Reaction to the launch of the report has been mixed with WWF stating,
“This could be a turning point for the UK’s relationship with the environment, where we begin to restore nature rather than destroy it. The plan is an important first step, but the commitments will only become a reality if they are backed by the force of law, money and a new environmental watchdog with the power to make sure the government lives up to its promises.”
The plan also describes plans to investment £10 million in a schools initiative, called the Nature Friendly Schools Programme, to target children in the most disadvantaged areas of the UK. This funding will come from the Department for Education budget and be spent over five years.
Much coverage of the report’s launch focused on reducing single-use plastics from supermarket food packaging – an initiative described as a major part of the Government’s plan to make Britain a global leader on tackling plastic waste. But the government’s plans for plastic waste do not go far enough, say environmentalists. Tanya Steele, CEO of WWF, said: “We welcome any step to reduce the plastic waste we produce, and policies like this can spur change. But if we really want to solve this problem, we need to think bigger and ultimately move towards an end to single-use plastics.”
Conservation bodies felt that a lack of legal underpinning was a fundamental flaw and environmental groups criticised the lack of proposed legislation and the lengthy timescales for dealing with problems.
“It has been (rightly) criticised for being vague and lacking detail regarding how it will be implemented, but it can’t be criticised for lack of content. Within the 151 pages are a wide range of promises, from the creation of a northern forest and a network of green corridors, to new green infrastructure arising from development.
There is a lot here to welcome, however the lack of specifics is concerning, and the dissonance between some of the aspirations and the context in which they need to delivered (austerity, the weakness of the planning system and the crisis facing our parks and open spaces) is jarring. It takes a leap of considerable faith to see some of these welcome words being translated into effective action.”
Common land and uplands appear to have been ignored with the Government’s failure to mention them in its environment plan following earlier extensive consultation.