Risk Based Performance Forecast of Flood Defences Affected by Changing Environments
Lead Research Organisation:
University of Greenwich
Department Name: Sch of Engineering
Abstract
Flooding is a growing problem in the UK and causes extensive damage to infrastructure, homes and business. Recently, the problem was highlighted again due to severe flooding in 2013/14 winter, causing total economic losses of over £1 billion. Earth dykes, used as major flood defence structures in the UK, can fail in extreme events, as evidenced by the numerous breaches along earth embankments during the December 2013 East Coast surge event. Earth dykes even become more vulnerable due to changing operation conditions caused by climate change.
The project addresses strategic issues associated with changing environments and deteriorating flood defence systems at a UK national level, which have been identified by HR Wallingford and the Environment Agency. The outcomes of the project will contribute towards developing next generation risk based performance evaluation and prediction methodology for reducing flood risk, improving resilience of flood defences to changing environments, and determining optimum maintenance strategies. The methods developed in this research will be implemented into flood risk management framework through HR Wallingford who currently lead the technical development of the flood risk assessment methodology used by the Environment Agency.
The project addresses strategic issues associated with changing environments and deteriorating flood defence systems at a UK national level, which have been identified by HR Wallingford and the Environment Agency. The outcomes of the project will contribute towards developing next generation risk based performance evaluation and prediction methodology for reducing flood risk, improving resilience of flood defences to changing environments, and determining optimum maintenance strategies. The methods developed in this research will be implemented into flood risk management framework through HR Wallingford who currently lead the technical development of the flood risk assessment methodology used by the Environment Agency.
Publications
Chen H
(2019)
Reliability analysis and optimum maintenance of coastal flood defences using probabilistic deterioration modelling
in Reliability Engineering & System Safety
Chen, H.-P.
(2015)
Time-dependent reliability analysis of coastal defences subjected to changing environments
in Structural Monitoring and Maintenance
Mehrdad Bahari Mehrabani
(2016)
Markov Chain modelling for life-cycle performance assessment of coastal flood defences.
Nepal J
(2015)
Risk-based optimum repair planning of corroded reinforced concrete structures
in Structural Monitoring and Maintenance
Nepal, J.;Chen, H.-P.; Gouldby, B.; Simm, J.;
(2017)
Translation of expert judgement based condition grading to state-based probabilistic deterioration modelling of flood defences
in Journal of Flood Risk Management (in preparation)
Nepal, J; Chen, H.-P.; Gouldby, B.; Simm, J.;
(2016)
Reliability-based performance assessment of flood defence assets using state-based stochastic deterioration modelling
Nepal, J; Chen, H.-P.; Gouldby, B.; Simm, J.;
(2015)
Markov chain based stochastic deterioration modelling of repaired flood defence structures using evolutionary algorithm
Nepal, J; Chen, H.-P.; Gouldby, B.; Simm, J.; Tarrant, O.
(2015)
State-based stochastic performance deterioration modelling of flood defence assets
| Description | The project addresses strategic issues associated with changing environments and deteriorating flood defence assets at a UK national level, which have been identified by HR Wallingford and the Environment Agency. The key achievements of the research are summarised as follows: - translated the existing expert judgement based deterministic asset deterioration curves to the state-based probabilistic deterioration models with consideration of uncertainties. - Investigated the influence of structural repairing on the probabilistic performance deterioration of flood defence assets. - Implemented the developed state-based stochastic deterioration models into time-dependent reliability analysis. - Investigated the time-dependent fragility curves for various types of flood defence assets. |
| Exploitation Route | The outcomes of the project contributes towards developing next generation risk based performance evaluation and prediction methodology for reducing flood risk, improving resilience of flood defences to changing environments, and determining optimum maintenance strategies. The methods developed in this research are implemented into flood risk management framework through HR Wallingford who currently leads the technical development of the flood risk assessment methodology used by the Environment Agency. |
| Sectors | Communities and Social Services/Policy,Construction,Education,Energy,Environment,Transport |
| Description | The research has made a number of positive impacts, and has been successfully implemented into two case studies: earth dykes at Thames Estuary and Humber Estuary. This work provides new measures for forecasting the performance of flood and coastal defence systems, including - Assisting the Environment Agency in their climate change adaptation planning, by providing more robust estimates of flood defence deterioration processes. - Assisting in managing the likelihood of flooding and erosion by quantitatively analysing changes in risks due to asset deterioration and in optimising the maintenance strategies for flood and coastal defence systems; - Raising awareness through publicity campaigns and provision of information on flood and erosion hazards on the basis of this new asset performance evaluation and prediction methodology. The application of the developed risk based performance forecast of flood defences reduces the damage due to flooding and thus generate significant economic impact. The findings of this project have been disseminated widely by various ways including presenting papers in international conferences |
| Sector | Communities and Social Services/Policy,Construction,Energy,Environment,Transport |
| Impact Types | Societal,Economic,Policy & public services |
| Description | Research and application |
| Geographic Reach | National |
| Policy Influence Type | Influenced training of practitioners or researchers |
| Impact | The methods developed in this research are implemented into flood risk management framework through HR Wallingford who currently leads the technical development of the flood risk assessment methodology used by the Environment Agency. |
| Description | Monitoring based performance assessment of civil infrastructure |
| Amount | £23,900 (GBP) |
| Funding ID | NRCP/1415/14 |
| Organisation | Royal Academy of Engineering |
| Sector | Charity/Non Profit |
| Country | United Kingdom |
| Start | 03/2015 |
| End | 02/2016 |
| Title | Research tool |
| Description | A new methodology for risk based performance forecast of flood and coastal defences due to changing environments was investigated during this research to support HR Wallingford's flood management framework that has been widely used by the Environment Agency. This work provides scientific basis for next generation asset performance forecast methodology, leading to the change from current crude condition grading by expert judgement to quantitative performance prediction by stochastic modelling for flood and coastal defence systems affected by changing operation conditions. |
| Type Of Material | Data analysis technique |
| Year Produced | 2016 |
| Provided To Others? | Yes |
| Impact | The methods developed in this research are implemented into flood risk management framework through HR Wallingford who currently leads the technical development of the flood risk assessment methodology used by the Environment Agency. |
| Description | Industrial Partner |
| Organisation | HR Wallingford Ltd |
| Country | United Kingdom |
| Sector | Private |
| PI Contribution | Greenwich will manage the project and undertake the practical work under the guidance of HR Wallingford. |
| Collaborator Contribution | The stakeholder HR Wallingford is responsible for steering the project in close collaboration with Greenwich, providing the available resources and data for the research, reporting the outcomes of the research, and implementing the findings into their flood management schemes. |
| Impact | The outcomes of the project contributes towards developing next generation risk based performance evaluation and prediction methodology for reducing flood risk, improving resilience of flood defences to changing environments, and determining optimum maintenance strategies. The methods developed in this research are implemented into flood risk management framework through HR Wallingford who currently leads the technical development of the flood risk assessment methodology used by the Environment Agency. |
| Start Year | 2014 |
| Title | Product |
| Description | This work provides scientific basis for next generation asset performance forecast methodology, leading to the change from current crude condition grading by expert judgement to quantitative performance prediction by stochastic modelling for flood and coastal defence systems affected by changing operation conditions. |
| Type Of Technology | New/Improved Technique/Technology |
| Year Produced | 2015 |
| Impact | The research has made a number of positive impacts, and has been successfully implemented into two case studies: earth dykes at Thames Estuary and Humber Estuary. This work provides new measures for forecasting the performance of flood and coastal defence systems. |
| Description | Flood & Cost 2016 |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | Flood & Coast 2016 is a unique event which will advance the debate about flood and coastal erosion risk, resilience and response between government bodies and local authorities with business, major infrastructure and asset managers, as well as affected communities (from the web). |
| Year(s) Of Engagement Activity | 2016 |
| URL | http://www.floodandcoast.com/index.php |
| Description | Presentation of Research Results to CIRIA |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Professional Practitioners |
| Results and Impact | An event invited by CIRIA to show the latest research results to industry, i.e. Innovation Showcase: Environmental Risks to Infrastructure. |
| Year(s) Of Engagement Activity | 2016 |
| URL | https://www.ciria.org/CIRIA/Navigation/Events/Event_Display.aspx?EventKey=E16246 |
| Description | Workshop to CH2M and Environment Agency |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | Regional |
| Primary Audience | Professional Practitioners |
| Results and Impact | Workshop for Environment Agency and CH2M for Thames Estuary Asset Management 2100 programme. |
| Year(s) Of Engagement Activity | 2016 |
| URL | https://www.gov.uk/government/news/thames-estuary-asset-management-2100-programme-team2100 |