iCASP’s Dr Jenny Armstrong and Dr Ben Rabb, working in collaboration with the Priestley International Centre for Climate have contributed to two chapters – one on the climate science focusing on the increased risks of flooding and droughts and the second suggesting ways in which we can work with natural processes to improve the resilience of households. 2019 was a record breaking year for both hot weather and autumn rainfall with the UK experiencing the hottest summer and warmest winter days ever recorded. This came on the back of the prolonged heatwave and joint hottest summer season on record in 2018. While insurance claims arising from too much water resulting in flooding are the stories we usually hear, there was also a surge in insurance subsidence claims as a result of the hot, dry conditions.
1.8 million people in the UK currently live in areas at significant risk from flooding, and this number is growing. If the current rate of warming continues the number of people at risk could rise to 2.6 million in as little as 20 years.
While our homes may be at risk, they are also a contributing factor to rising emissions. Heating and hot water in UK homes currently makes up 25% of total energy usage and 15% of greenhouse gas emissions, and more housing is planned.
The report highlights a range of actions that can be taken; from decarbonising our homes to reduce emissions to improving the resilience of households to the impacts of climate change. Suggested actions don’t just happen in our home, for example peatland preservation can not only sequester carbon helping reduce total emissions, but also reduce surface water runoff and in turn reduce flood risk.
Publication of the report marks the launch of the annual #ShowTheLove campaign from the Climate Coalition. Every February since 2015, people are encouraged to show the love for the things they want to protect from climate change, and showcase the ways they can create a safer world for future generations. Actions include making and sharing green hearts, writing to local MPs and starting conversations about climate change.
The Climate Coalition is the UK’s largest group of people dedicated to action against climate change. Along with their sister organisations Stop Climate Chaos Cymru and Stop Climate Chaos Scotland, they are a group of over 140 organisations — including the National Trust, Women’s Institute, Oxfam, and RSPB — and 22 million voices strong.
The cost of the 2015 Boxing Days floods was £47M in Calderdale alone, and the indirect knock-on effects to the regional economy was £179M. This is just from one flood event. In every flood event there is the immediate damage, loss and destruction which is often highly visible; the knock-on effects which are wide-reaching and significant are not always so obvious. With climate change we are likely to experience more extreme weather events that can lead to flooding, so we need to improve our resilience across society.
The Small and Medium Enterprise (SME) sector can be highly
vulnerable to flood impacts. Because a large proportion of the private sector
is made up of SMEs – about 99% of Yorkshire’s private sector is made up of SMEs
– flooding can have a massive impact across the wider region reaching areas
outside those that were flooded.
Our newest iCASP project seeks to address this issue through
supporting the SME sector to become more resilient to the impacts of flooding
so the negative impacts on the wider economy are reduced.
Currently there is a large knowledge gap about the impacts of flooding upon SME businesses; this lack of knowledge extends from the SMEs themselves, through insurers and lenders, local and sub-regional authorities to national government. The effect of this knowledge gap can mean SMEs not understanding how to protect themselves adequately, and insurers or lenders not understanding the risks and so not providing lending or insurance. At the government level this lack of knowledge can manifest as a lack of appropriate funding being included in businesses cases and missed opportunities for evidenced resource allocation and investment in preventive measures.
This project will bring together local authorities and the insurance sector to help them improve their understanding of the impacts of flooding upon SMEs, identify how they can support the sector to become better prepared for floods and help prioritise their responses if and when flooding occurs. A key aspect of the project will be a robust methodology that can be used to assess the direct and indirect costs of flooding. This will enable local authorities (LAs) to carry out future flood assessments and subsequently develop evidenced and robust business plans for funding to support better responses for any future flooding.
“The Leeds City Region Flood Review was published in 2016 and developed in partnership between West Yorkshire Combined Authority/LEP, local authorities, Yorkshire Water and the Environment Agency. The Review and its 19 recommendations aim to implement a more consistent and effective approach to both flood risk management and mitigation, and responding to future flood events across the City Region. Recommendation 3 of the Review relates directly to this project as it confirms the urgent need for a robust regional formula for modelling the indirect economic impact of flooding”.
The ability of lenders and insurers to accurately assess and understand the likely risks of flooding will enable them to understand the right level of risk, develop new products and properly price the current products unlocking access to them for SMEs who may currently be unable to do so. An improved understanding of the effectiveness of different protection and resilience measures could also boost an increase in lending for preventive purposes and thus better uptake of these important measures to improve resilience.
“The work package on insurance will cover an important gap as it provides valuable information to insurers/lenders and surveyors to increase our understanding of SME flood risk. When I hold my regular meetings with insurers, they are bought into the concept of resilience, but cannot move forward meaningfully to acknowledge it without more information and evidence. They want to understand from SMEs what is the real financial impact of a flood. But also, what difference in financial terms has, or could, a resilient strategy make to the cost of the claim. The tool that the project will co-create to assess the effectiveness of resilience measures will be key to identifying the most beneficial strategies SMEs can take to protect themselves”.
Insurance broker specialising in flood risk
As with all iCASP projects this has been co-designed and will be carried out in close collaboration with partners and stakeholders. Co-creation ensures efforts are joined-up to support widespread uptake in the Yorkshire region, and nationally, to spread the benefits of closing this current gap in our knowledge. This exciting new project will push the limits of our understanding on the economic impacts of flooding on SMEs and the effectiveness of property flood resilience measures. And, in collaboration with the City of York Pathfinder project “Yorkshire Future Flood Resilience”, it will work to improve the uptake of Property Flood Resilience across Yorkshire and the UK.
Two new jobs have been created to deliver this project:
As part of the Natural Flood Management (NFM) work being undertaken on the Calderdale Flood Action Plan, which iCASP’s Calderdale NFM project is contributing to, three sub-catchments in Calderdale are being modelled to improve understanding of how the current land management impacts upon flooding.
On 14 November, Tom Willis held a workshop to explore the modelling work he has been undertaking. Tom has been using SD-TOPMODEL which helps identify which areas of the 3 sub-catchments contribute most to flooding in the lower valley. Knowing which parts of a catchment contribute most to peak flows makes it easier to assess the impact of locating an NFM measure in one place rather than another, and allows prioritisation of those measures that will have the greatest benefits.
Having seen how the model works, workshop participants could apply their knowledge and insight of the catchment into devising different scenarios for the next on-the-ground stage of the project. They then live-tested them during the session to see their impact upon peak flood levels
The next steps in this project will be the creation of a
handbook to assist landowners and managers in targeting the most appropriate
NFM measures across the catchment.
At times when we experience floods, such as those currently devastating people’s homes and businesses in parts of Yorkshire, Derbyshire and Nottinghamshire, it is very common to see people attempting to distill the problem down to a single cause. In complex hydrological systems there is no sense in taking this simplistic approach; rather the whole catchment needs to be considered and we need to think about how we make entire catchments more resilient to extreme events. This is one reason for the ’i‘ in the NERC-funded Yorkshire Integrated Catchment Solutions Programme (iCASP). We work on the understanding that what happens in one area of the catchment affects other parts of the catchment because it is a whole system.
Our work looks at how processes integrate across the entire catchment and while finding solutions to environmental problems we also seek ways to address multiple problems at once, thereby delivering value for money. It isn’t just physical elements of catchment management, there’s a human element too: we work closely with partners and stakeholders on all projects to build relationships and trust and to support organisations to work together in confidence to maximise beneficial outcomes.
Flood Forecasting, and Drought & Flood Risk Mitigation are two of our six workstreams that determine the work we fund. We draw upon the research of several universities in the region including the University of Leeds, University of Sheffield and the University of York to address problems that organisations across Yorkshire are seeking to tackle. This ranges from trying to improve the ability of local councils to respond to weather forecasts by improving the advice provided in a forecast, or implementing measures that slow the flow of water across the landscape so it takes longer to move into the rivers and doesn’t contribute to sudden peak flows.
Restoring the peatland in the upper reaches of a catchment means that rainfall there takes longer to move through and into rivers downstream. Our Peatland Restoration project has developed guidance for practitioners and managers to help their decision-making as to the best restoration techniques to return the system to its normal functionality of water storage and slowing downstream flow. An added benefit of this kind of restoration is that functioning peatland acts as a sink/store locking up carbon that might otherwise be driving climate change.
Natural Flood Management: modelling, mapping and monitoring
Several of our other
projects are on the same theme as this: using natural processes to slow and
store water moving through the landscape to avoid the mass flows and peaks that
cause problems. There are many Natural Flood Management (NFM) pilot projects
throughout Yorkshire funded by government. Our iCASP projects are supporting
these by working with partner organisations to develop modelling, mapping and
We use computer models to understand which parts of a catchment contribute greater quantities of water into a watercourse than other parts, and to understand the role that landscape features – both natural and human-made – may play in this process either slowing or storing water. Our modelling expertise is currently being used in our Calderdale NFM project to understand how three tributaries contribute to water flows further downstream.
Combining rainfall data and
high resolution terrain data, combined with the knowledge gained from site
visits means we can create ‘Opportunity Maps’ that allow an identification of
what the current landscape management means for flood risk and what might be
done in future.
Once developed, Opportunity Maps allow us to identify locations where NFM interventions such as tree planting, aerating soil, buffer strips or leaky dams may best be sited for maximum effect. In the case of our Don Catchment project, we work with the land managers to identify which interventions could be installed by volunteers, what interventions would be best and where our mapping allows us to identify the additional impacts these interventions may play. Many NFM interventions can serve multiple purposes; they may not only slow down the flow of water across the landscape, but they might also improve water quality or provide valuable habitat for wildlife, contributing to improved biodiversity and species richness in an area.
“We feel very privileged to have benefited from our involvement in iCASP, as it has given us access to expertise that has resulted in opportunity maps that are guiding our decision-making in relation to our Hidden Heritage Secret Stream (HHSS) project. These maps identify locations in the landscape where we can have the most impact, and they have also helped highlight the types and locations of NFM interventions that not only slow the flow of runoff, but also reduce diffuse pollution and increase ecological connectivity across the landscape. Our team is using the maps to identify sites for investigation on the ground, and they have been very useful when engaging with our partners and landowners.”
Ed Shaw, Director Don Catchment Rivers Trust
Monitoring the impact and effectiveness of NFM interventions is critical; both to being able to identify what impact is delivered, but also in being able to make the case for funding such measures and for their ongoing maintenance. A key aim of another of our Natural Flood Management projects is to improve the monitoring capability of those using NFM so they are able to carry out rigorous monitoring to contribute to the evidence base for this kind of flood risk intervention.
In our Payment for Outcomes project we are working with the National Trust to build NFM measures into their payment for outcomes trial. Farmers on some of the Trust’s tenanted farms will receive payment for the environmental outcomes they achieve, and this work will eventually inform Defra’s new Environmental Land Management Scheme and show how NFM can be integrated within this.
To maximise all the benefits of this work, we’ve developed a Natural Flood Management Community of Practice (CoP) to bring together people working on NFM to share skills, experience and best practice, build capacity and discuss challenges and opportunities. The CoP meetings draw upon the expertise we are deploying in the NFM projects we work on and also brings together people from across the region – and increasingly from beyond it too – to understand how best to manage their areas of land in the most appropriate ways for our future climate.
Slowing the flow of water through a catchment, and the measures put in place to do this are just one aspect of the measures we are working on. As demonstrated in the last week, at times rainfall is extreme and even if there are lots of interventions in place upstream, the sheer quantity of water is overwhelming, so we also work on improving flood forecasting. Our Enhanced Surface Water Flood Forecasts project worked with a range of partners to trial new forecasting software to assess whether it helped flood risk managers and emergency responders in the decision-making processes they go through in a flood event.
“In response to Defra’s Surface Water Management Action Plan, the Environment Agency and Met Office are scoping a new capability for sharing with responders very short range and rapid update forecasting (“nowcasting”) for the type of rainfall that causes surface water flooding. The Enhanced Surface Water Flood Forecasts project final report, including feedback from the incident response workshop, has provided valuable information and user response insight for the discovery phase of this project and we expect that continued engagement with the iCASP team will continue to be beneficial for understanding user needs and exploring piloting opportunities.”
Graeme Boyce, Project Executive, Flood Forecasting Centre
Our Living With Water Catchment Telemetry Integration project, which the Living with Water Partnership are undertaking in Hull, will bring together remote monitoring data of water flows carried out by several organisations with decision-making software to create a tool that will help deliver operational preparedness for events such as those we have seen in the last week and identify optimal locations for future monitoring. Combining such data collected by these organisations has not been done at this scale before; this way of joint working will be extremely powerful in making higher levels of knowledge available to decision makers and first responders about actions to take and deployment of flood defences.
Our newest project – Bridging the knowledge gap to boost SME resilience – starting later this month will be working on ways to build the resilience of the SME sector. Here in Yorkshire, much of the private sector is made up of SMEs who can be very vulnerable to flooding and the knock–on effects to the regional economy of a flood event can be significant and far-reaching. The project will work with local authorities and the insurance sector to develop a robust methodology for assessing the direct and indirect costs of floods on the SME sector so they are able to tailor their flood assessments and responses appropriately. By providing detailed information on the effectiveness of resilience measures and risk reduction activities, flood risk can be properly priced and managed by SMEs and appropriate support can be given to SMEs to make them more resilient and able to reduce their risks. Local Authorities will be better able to carry out future flood assessments, lobby for additional funds to better prepare for future flooding and, in the event of a flood, prioritise their response in a consistent and timely manner.
This just a snapshot of some of the work we are undertaking to produce solutions to water challenges across Yorkshire, the UK and globally. Our work extends right across catchments, from high and remote peatlands where some of the water that floods peoples’ homes begins its journey, to the streets where we live and the monitoring and forecasting that takes place to try to improve the way we respond, the advice given and the deployment of measures to reduce flood risk.
“Over time, we are increasing the number and diversifying the types of flood management techniques that will reduce peak flows downstream providing new tools to support farmers, villages, towns and cities susceptible to floods.”
Joe Holden, Director, iCASP
The environment is a complex system and we need to work at many different levels to tackle integrated problems. With climate change increasing the likelihood of extreme weather events, it is clear that we need to continue to invest in ways to address resilience and to use a wide range of solutions across the landscape to tackle flooding, rather than think about each component of the system in isolation.
In 2008 Joe Holden and colleagues published research that showed how water running over Sphagnum on blanket peatlands moved much more slowly (often ten times slower) than water running through sedges or bare peat. This spawned a new body of research which has shown how revegetation of peat, particularly if it is possible to get a dense Sphagnum cover, can slow the flow of water during storm events to reduce the flood peak downstream. The research indicates priority areas in the landscape for dense surface revegetation that will generally maximise flood benefits. Given that research has also recently shown sediment release from bare peat strongly influences peatland stream ecosystems this gives added impetus to revegetating peatlands and enhancing Sphagnum cover to achieve maximum downstream benefits for river habitats and flood risk.
Unlike most soil types where movement of water through the
soil attenuates the rate of water loss into rivers, research has shown that
water movement in blanket peatlands tends to be dominated by flow very close to
the surface or at the surface1. This means large volumes of
water move over short periods of time, associated with rainfall or snowmelt,
producing very high flow peaks in blanket peatland rivers compared to the flows
that occur during dry weather2, 3. The condition of the
peatland surface may therefore be crucial in determining the downstream flood
peak during storms.
Over a decade ago research was published that showed how water running over Sphagnum on blanket peatlands moved much more slowly than water running through sedges or bare peat4. This spawned a new body of research which tried to establish whether such effects made any difference to riverflow. This work, which included both empirical field demonstrations5, 6 and modelling experiments7-9, has now shown that revegetation of peat, particularly if a dense Sphagnum cover can be achieved, can slow the flow of water during storm events reducing the flood peak downstream. These effects hold (and can be proportionally greater) even for the very largest storm events10. The research indicates priority areas for the densest revegetation in the landscape to maximise flood benefits. These areas include strips of peatland several metres wide that run either side of streams, ditches and other watercourses, and areas of peatland covering other gently sloping parts of the catchment.
Research has also recently shown that sediment release from bare peat strongly influences peatland stream ecosystems11, 12 affecting both their biodiversity and functioning. This shows that we need to do all we can to disconnect sediment sources from the peatland streams. The most effective way to do so is to support revegetation of peatlands, especially near any watercourses. Thus, targeted restoration work that aims to achieve an end-point with a dense Sphagnum understorey will deliver maximum downstream benefits for river habitats and flood risk, while simultaneously adding resilience to the peatland ecosystems in the face of climate change, drought and wildfire.
J. & Burt, T. P. Runoff production in blanket peat covered catchments.
Water Resources Research 39, 1191, doi:10.1029/2003WR002067 (2003).
2. Acreman, M. & Holden, J. How
wetlands affect floods. Wetlands 33, 773-786, doi: 10.1007/s13157-013-0473-2
3. Price, J. S. Blanket Bog in Newfoundland
2. Hydrological Processes. Journal of Hydrology 135, 103-119 (1992).
4. Holden, J. et al. Factors affecting
overland flow velocity in peatlands. Water Resources Research 44, W06415, doi:
5. Grayson, R., Holden, J. & Rose, R.
Long-term change in storm hydrographs in response to peatland vegetation
change. Journal of Hydrology 389, 336-343 (2010).
6. Shuttleworth, E. L. et al. Restoration
of blanket peat moorland delays stormflow from hillslopes and reduces peak
discharge. Journal of Hydrology X 2, 100006 (2019).
7. Gao, J., Holden, J. & Kirkby, M. J.
A distributed TOPMODEL for modelling impacts of land-cover change on river flow
in upland peatland catchments. Hydrological Processes 29, 2867-2879, doi:
8. Gao, J., Holden, J. & Kirkby, M. J.
The impact of land-cover change on flood peaks in peatland basins. Water
Resources Research 52, 3477-3492 (2016).
9. Lane, S. N. & Milledge, D. G.
Impacts of upland open drains upon runoff generation: a numerical assessment of
catchment-scale impacts. Hydrological Processes 27, 1701-1726 (2012).
10. Gao, J., Kirkby, M. & Holden, J. The
effect of interactions between rainfall patterns and land-cover change on flood
peaks in upland peatlands. Journal of Hydrology 567, 549-559 (2018).
11. Aspray, K. L., Holden, J., Ledger, M. E.,
Mainstone, C. & Brown, L. E. Organic sediment pulses impact rivers across
multiple levels of ecological organisation. Ecohydrology doi: 10.1002/eco.1855
12. Brown, L. E. et al. Sediment deposits
from eroding peatlands alter headwater river invertebrate biodiversity. Global
Change Biology 25, 602-619 (2019).
Until 15 January 2020, iCASP will be carrying out a survey to better understand people’s views on measures to avoid flooding, in particular, Natural Flood Management (NFM).
We invite anybody who is interested or involved in NFM to take part and share your views. We want to hear about, and better understand, how you feel about NFM. You may have been a volunteer installing NFM interventions, or own land where NFM measures have been installed, you may have walked past some when out and about, or you may not have encountered them at all – whatever your experience, we would like to hear what you think about them.
Over the last few years there have been a wide range of NFM measures implemented across the UK. Here in Yorkshire we have several pilot schemes being trialled and monitored to build up our understanding of the processes, benefits and considerations when installing these kinds of flood measures.
Understanding how people perceive NFM, their levels of knowledge of different interventions and their views on NFM allows us to ensure this is considered when designing future schemes so that they are more acceptable and the benefits are more clearly articulated.
On 28 October, Dr Alison Dunn, lead academic on iCASP’s Invasive Non Native Species (INNS) project gave a keynote presentation at the International Conference on Aquatic Invasive Species about the growing problem of invasives, and the work she is doing to address this.
Because of the growing threat that some invasive species pose to our natural environment, and even in some cases to human health, there’s a real need to stop or dramatically slow their spread. One example of a particularly nasty invasive species is Giant Hogweed , a plant that can cause severe burns on human skin resulting for some people in long-term skin sensitivity problems; the current cost to UK local authorities of tackling this particular plant species is over £365,000 a year. It is this growing problem and cost of dealing with invasive species that is the driver for much of Dr Dunn’s work.
Her iCASP project is breaking new ground by working with local authorities to improve their biosecurity policies and procedures, and embedding this into their routine activities to slow the spread of invasive species. The project draws upon learning from another of her projects working with several organisations in the heart of the Yorkshire Dales to ensure that learning, resources, and successful ways of improving biosecurity are shared.
Local organisations and authorities are not the only people whose awareness and actions Dr Dunn is seeking to change; she gave evidence to the House of Commons Environmental Audit Committee’s inquiry into Invasive Species earlier this year stressing the importance of improved and robust biosecurity:
“Check Clean Dry and Be Plant Wise are flagship campaigns by DEFRA and we have found that where people are aware of those campaigns, their biosecurity behaviour does change, but awareness is not very high”
The report of the inquiry was published last week and biosecurity features strongly in the recommendations from the Committee to the Government. We now need to wait for the government’s response and whether changes are made to policy and legislation longer term.
The INNS iCASP project runs for another year and seeks to develop guidance and biosecurity protocols that will be embedded within local authorities across the Yorkshire region and will ultimately be made available to be used by organisations worldwide to help slow the spread of INNS.
iCASP is working on a project to integrate Natural Flood Management (NFM) into the National Trust’s ‘Payment for Outcomes’ trial. The Trust are undertaking the trial on some of their tenanted farms working with the Yorkshire Dales National Park Authority and Yorkshire Dales Rivers Trust. Their work will help to inform Defra’s new Environmental Land Management Schemes (ELMS). It seeks to pay for farmers for the environmental outcomes they achieve on land they farm.
The iCASP project is focused on identifying opportunities for NFM measures and discussing with farmers how NFM could fit into a payment scheme that would make business sense for them. These valuable insights will help inform future payment schemes which focus on payment for outcomes.
iCASP produced maps of each farm showing the parcels of land tenanted from the National Trust. The land parcels were overlaid on to maps, produced from SCIMAP. These maps show areas of risk related to diffuse pollution (e.g., fine grained sediment) and the connectivity of overland flow of water to the main channel network – together, these maps show which areas of land could benefit from further management. This allows us to generate ‘opportunity maps’ that indicate where NFM interventions might best be sited; for example installation of a leaky dam in a particular location might work well to slow peak flows of water or buffer strips to help reduce sediment (soil) being washed away.
Ground-truthing of the map outputs is crucial to understand the farm in more detail to ensure NFM opportunities are placed in the correct locations. For example, smaller flow pathways that connect sediment and water to the main channels, may not have been picked up during the modelling due to the resolution of data used. Speaking to the land owner is vital at this point to understand how the land is currently used and managed and where there are current issues (e.g., waterlogged soil). This is another layer of information that can be used to ground-truth the modelling output and also verify the locations of potential NFM interventions.
We have recently visited five farms taking part in the trial to do this ground-truthing. This has meant we’ve been able to annotate all the maps to verify the modelling output. This has allowed us to come up with a better understanding of which NFM interventions could be used and their locations on the farms.
The next step in this process will be to meet with all the farmers and other organisations involved in the project to share the knowledge gained by the process and produce final maps of the suggested interventions. Meeting with the farmers will also provide valuable feedback on the opinions of NFM, which interventions the farmers would be willing to install on their land and how these efforts might be incorporated into a payment scheme that pays the farmer for the environmental benefits they produce by installing NFM. iCASP will feed the key points of these discussions to DEFRA to inform the development of ELMS as well as share this useful insight with other projects looking at payment for outcomes (e.g. the Horizon 2020 CONSOLE project iCASP is part of). The National Trust will use the insights evaluate how NFM could be incorporated into their Payment for Outcomes trial.
iCASP academics been involved with work in Calderdale that aims to reduce the flow of water through the catchment using Natural Flood Management (NFM) measures. The iCASP project has been using a rain-fall run-off model, SD-TOPMODEL, to help with identifying which areas of 3 sub-catchments of the Upper Calder River contribute most to peak flows. Understanding which parts of a catchment are contributing most to flooding in the lower valley make it easier to assess the impact of locating an NFM measure in one place rather than another and allow prioritisation of those measures that will have greatest benefits.
The model produces maps like the one below that shows the speed at which water is flowing and uses rainfall data from nearby weather stations and high resolution terrain data. This modelling is combined with on-the-ground visits and meetings with landowners, land managers and flood risk managers to get the fullest picture of what is going on across the landscape when it rains.
The modelling and site visits improve understanding of what contributions existing landscape features already make; for example hedges and walls can help slow the flow of water across the land and by acting as a temporary store help reduce the peak flows of water. These aspects can then be included to further improve the representation of these features in the model. The modelling and site visits also allow experts to identify where in the landscape new NFM features can be located to further slow and store water.
At a meeting in November the modelling results will be presented to all the partners working on flood measures in Calderdale. From these results a handbook will be created to assist land owners in targeting appropriate NFM interventions, and to further understand how the whole catchment responds during flood events.