Quantitative Assessment Tool for Wind Effect on Wave Overtopping Seawalls

Lead Research Organisation: Manchester Metropolitan University
Department Name: Sch of Computing, Maths and Digital Tech

Abstract

Climate change is expected to result in stronger and more frequent winds, storms and sea level rise, leading to more severe adverse effects on infrastructure such as flooding damage to buildings, power stations, railways and sea defences. The effects of this natural hazard have been frequently seen in recent flooding events in the UK and other countries worldwide. Over recent years, Royal HaskoningDHV has reported that wind effects on wave overtopping has become an increasing concern for the design of modern sea defences and the management of coastal flood risk. This threat can cause unexpected coastal flooding and pose additional flooding risks to coastal infrastructure, particularly in the UK as an island nation.
Currently, there is no reliable tool to quantify such risk. Present engineering practice is to either (i) ignore wind effects, which would put protected areas at risk, or (ii) include a large safety margin, which would significantly increase the cost of coastal defences unnecessarily. The safety margin method is also restricted to existing known coastal scenarios and cannot provide reliable assessment of the risks as climate changes. This is a clear knowledge gap that causes a growing concern for the ability to adequately and economically control coastal flood risk. The proposed project brings together leading experts from Manchester Metropolitan University, Royal HaskoningDHV, HR Wallingford, Environment Agency, EDF Energy and Torbay Council to address the concerns by developing a novel assessment tool to quantify wind effects on wave overtopping. Its aim is to translate the powerful two-fluid model from Manchester Metropolitan University into an engineering tool to quantify wind effects on wave overtopping, accounting for the effects of sea level rise. The objectives are to (a) adapt an advanced in-house two-fluid model for wind effects on wave overtopping, (b) validate the model rigorously against physical modelling tests undertaken at HR Wallingford, field data and real engineering application cases including ongoing or recently completed projects with the Environment Agency, SEPA and EDF Energy by Royal HaskoningDHV, (c) build a companion database to facilitate efficient assessment of the risk in design and management, and (d) enclose the tool and database in a simple user-friendly interface for efficient management and control of coastal flooding. Key activities also include visits to Heysham and Torbay for the collection of sea defence data and past event data where wind effects were significant on wave overtopping. The project partners will contribute to the supervision and steering of the project and provide real cases and data. This will be the first practical tool for accurately quantifying wind effects on wave overtopping. It will inform and improve current engineering practice, removing the need for large safety margins to account for wind effects in infrastructure design and assessment.
The main deliverables and outputs will be an assessment tool and a companion database. These tools will be used by Royal HaskoningDHV in the flood risk assessment, engineering design and coastal flood forecasting system, by EDF Energy to enhance the assessment of risks of coastal flooding to existing and new build power plants, by the Environment Agency for an improved coastal flood warning service and by Torbay Council for improving the flood risk management and supporting decisions relating to future development and emergency planning. The developed tool has the potential to become a vital design tool in assessing wind effects on wave overtopping, benefiting various organisations such as the Scottish Environment Protection Agency, Natural Resources Wales, Network Rail and Transport Scotland for the multiple purposes of planning strategic or investment decisions in management of coastal flooding risks to infrastructure. The project will last 14 months with a total cost of £159k at 80% FEC.

Planned Impact

The overall objective is to develop a reliable tool to quantify wind effects on wave overtopping, which is able to account for the effects of anticipated sea level rise and stronger wave/wind actions arising resulting from climate change. The main deliverables and outputs will be an assessment tool and a companion database. This will enable the project partners to make a reliable assessment of wind effects on wave overtopping for improved service in coastal flood forecasting and warning systems, and to optimise the design of infrastructure that is vulnerable to wave overtopping. It will greatly improve the safety performance of existing and new build infrastructure such as sea defences, railways and power stations. The developed tool will fill an important knowledge gap in coastal and maritime engineering practice. It has the potential to become a vital design tool in assessing wind effects on wave overtopping, benefiting many organisations such as the Environment Agency, Scottish Environment Protection Agency, Natural Resources Wales, Network Rail, Transport Scotland and local councils for the multiple purposes of safely planning strategic or investment decisions and effective management of coastal flood risks.

Publications

10 25 50
 
Description The wave overtopping volume will be increased significantly by wind at speed higher than 10 m/s.
Exploitation Route Optimise design of sea defences and help on management and control of coastal flooding.
Sectors Construction,Energy,Environment,Transport

URL https://jzhou99.wixsite.com/maclab/qatwewos-tool
 
Description The finding has been realised by the industrial project partners and agreed that it needs further quantitating in the database and the tool before the potential application in practical engineering. The achievements of the project have been reported by major engineering media such as US Stormwater (https://www.stormh2o.com/erosion-control/article/21117909/department-qa-protecting-coastlines-from-windblown-waves) and UK New Civil Engineer (https://www.newcivilengineer.com/innovative-thinking/simulation-tool-developed-to-improve-sea-wall-defences-31-10-2019/).
First Year Of Impact 2019
Sector Construction,Energy,Environment,Transport
Impact Types Societal,Economic

 
Title Tool 
Description A user graphical interface (GUI) as a tool to use the database is developed. 
Type Of Material Improvements to research infrastructure 
Year Produced 2018 
Provided To Others? No  
Impact The GUI is the first version based on the existing database and will be updated after the new simulation results become available. 
URL http://qatwewos.org.uk/news
 
Title Database 
Description Database is established for the basic combination of wind, wave and sea defences based on simulations. 
Type Of Material Database/Collection of data 
Year Produced 2018 
Provided To Others? No  
Impact No impact so far. 
URL http://qatwewos.org.uk/
 
Title Module 
Description The module for simulation of wind effect on wave overtopping in the framework of established open source software of OpenFOAM is developed. 
Type Of Material Computer model/algorithm 
Year Produced 2018 
Provided To Others? No  
Impact No impact. 
 
Description QatWeWos project website 
Form Of Engagement Activity Engagement focused website, blog or social media channel
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact Report research progress and raise public awareness of the risk.
Year(s) Of Engagement Activity 2018
URL http://qatwewos.org.uk/