MORPHINE: Re-designing the coast: The Morphodynamics of Large Bodies of Sediment in a Macro-tidal Environment

Lead Research Organisation: University of Nottingham
Department Name: Faculty of Engineering

Abstract

We propose developing the mathematical theory of morphodynamics as it pertains to a macro-tidal environment (coastal region with large tidal range, like that in the UK), so as to understand the movement of large deposits of sand on our beaches and shorefaces (shorefaces are, loosely, the regions in between the beach and the continental shelf floor). This theory will allow us to formulate a new mathematical modelling approach. New models stemming from this will allow us to develop a new approach to designing sea defences, in which large quantities of sand ("nourishments") are deposited at strategic locations at and / or near to the coastline. These nourishments will provide a source of sediment for beaches that are eroding, but, importantly, they will also alter local wave and current conditions, which will transform previously eroding beaches into more stable configurations, and so form naturalistic coastal defences.
The theory and the models, coupled with a new, realistic statistical model of sea conditions, will make it possible for us to predict the behaviour of these nourishments to a high degree of accuracy under different conditions. Because the models are highly efficient we will be able to do this for long times (say, 20 years or more), and to investigate the likely variations in wave conditions that might occur during this time. This will support the design of this new approach to designing sea defences, and will mean that we do not have to rely on invasive, expensive and reactive traditional sea defences. It will have the additional benefit of providing the means to predict how a major proportion of our existing coast will behave in the future. The proposal addresses UK conditions in particular, in which a very large tidal range combines with a wide variety of wave conditions to produce a particularly challenging environment. We are therefore proposing to undertake fundamental work on coastal morphodynamics so as to develop tools that will let us re-think our coastal defence strategy.

Planned Impact

+ Between 2005 and 2015 the UK government spent about £6 billion on flood and coastal erosion risk management, with the annual figure (most recently £795 million) having risen sharply over the last two years (about 62% of this is coastal flooding or erosion, according to previous estimates). The work proposed will result in a better understanding of coastal morphodynamics, around the UK coast in particular, and so the UK government will benefit in terms of better designed, more predictable, less invasive coastal defences. This will also save money in the future.
+ District councils, and all other bodies who manage the coastal environment will similarly benefit.
+ Coastal engineering consultants and contractors will benefit from more reliable numerical models, and a better understanding of these dynamics, so that traditional model output can also be assessed from a more knowledgeable perspective. Modelling may also be carried out faster using the amplitude equation approach.
+ The improved statistical model will also mean that coastal change can be assigned more reliable error estimates, thus reducing uncertainty. This will again help coastal managers, but also the insurance industry in producing better estimates of risk for homes / businesses at risk of flooding, thus reducing costs across the board.
+ In the future, tourists will benefit from fewer beaches being rendered unusable or unsightly, because the proposed coastal defence strategies involve longer-term solutions without recourse to hard engineering structures. This will similarly benefit local economies.
 
Description Proof of concept for description of aspects of natural morphodynamics using an amplitude equation. We have shown that a one mathematical equation can be used to describe some characteristics (e.g. lengthscale) and behaviour (long-term evolution) associated with natural beach morphologies.

Feb. 2019: The concept of a nourishment as a morphodynamic perturbation has been implemented in a mathematical model. In the first instance the cross-shore dynamics of a single shoreface nourishment has been examined. The resulting dynamics agree with the general observation that mild wave conditions promote onshore migration of the nourishment, whereas energetic waves promote offshore movement. The primary impact of tides in the cross-shore study is to alter water depth, thus making the nourishment more or less active. The concept therefore appears viable.
Exploitation Route The concept could be applied to artificial features, given the appropriate theoretical underpinning.

Feb. 2019: The modelling concept may allow design of nourishment location, size based on local beach profile and prevailing wave and tide conditions.
Sectors Energy,Environment,Other

 
Description Professors Dodd and Reeve provided brief technical advice to the Royal HaskoningDHV team responsible for the Bacton sandscaping project regarding the sediment composition of proposed sand nourishment and the limitations of current modelling tools.
First Year Of Impact 2017
Sector Construction,Energy,Environment
Impact Types Societal,Economic

 
Description Discussions with Royal HaskoningDHV 
Organisation Royal HaskoningDHV
Country Netherlands 
Sector Private 
PI Contribution Discussions between Prof N. Dodd (University of Nottingham) and Prof. D.E. Reeve (Swansea University) with two senior employees of Royal HaskoningDHV on their experiences / ideas regarding 'sandscaping'. Sandscaping is the commonly used terminology in coastal engineering for the deposition of large amounts of sediment at or near to the coast, so as to counteract / mitigate the effects of flooding and / or erosion. Reeve visited Nottingham, and Dodd and Reeve discussed this topic with the representatives of Royal HaskoningDHV about 60 minutes on 17.02.17. Originally, the meeting had been provisionally scheduled for Oct 2016, but Dodd's teaching timetable made that very difficult, so a later meeting was planned. A face-to-face meeting had then been scheduled, but there were problems communicating between the Royal HaskoningDHV representatives, hence the eventual skype meeting with one on speaker phone. It was decided that the next project meeting at Nottingham would be immediately followed by an in-person meeting with, if possible, both representatives from Royal HaskoningDHV. On 02.02.18 Royal HaskoningDHV were also present at the Bacton sandscaping meeting (see Key Findings) and further discussion were had with them. On Aug 21st, 2018 Prof Dodd and Prof Reeve met with a senior representative of Royal HaskongDHV at the University of Nottingham to discuss possible implementations of sandscaping solutions at various representative locations (i.e. scenarios). Discussions included the kinds of possible implementations, and the stability concept.
Collaborator Contribution Discussions between Prof N. Dodd (University of Nottingham) and Prof. D.E. Reeve (Swansea University) with two representatives from Royal HaskoningDHV on their experiences / ideas regarding 'sandscaping'. Sandscaping is the commonly used terminology in coastal engineering for the deposition of large amounts of sediment at or near to the coast, so as to counteract / mitigate the effects of flooding and / or erosion. One representatives (speaker phone) and the second (Skype) discussed this topic with Dodd and Reeve for about 60-90 minutes on 17.02.17. On 02.02.18 Royal HaskoningDHV were also present at the Bacton sandscaping meeting (see Key Findings) and further discussion were had with them. Royal HaskoningDHV were involved in setting up and running the meeting. On Aug 21st, 2018 Prof Dodd and Prof Reeve met with a senior representative of Royal HaskongDHV at the University of Nottingham to discuss possible implementations of sandscaping solutions at various representative locations (i.e. scenarios). Discussions included the kinds of possible implementations, and the stability concept.
Impact N/A
Start Year 2017
 
Description ITB - ICMSE Lecture 
Organisation Bandung Institute of Technology
Country Indonesia 
Sector Academic/University 
PI Contribution In October 2018 I visited Dr Magdalena (Department of Mathematics, Institut Teknologi Bandung, Indonesia), to give an invited lecture on 'Applying mathematics to the problem of coastal protection', as part of the 5th International Conference on Mathematics, Science and Education (ICMSE), Universitas Negeri Semarang, Bali, Indonesia. The work we are undertaking as part of the MORPHINE project formed an integral part of the talk.
Collaborator Contribution The extended an Speaker invitation to me and hosted my visit.
Impact One student from ITB had a 2 week visit to Swansea to undertake some experiments in our wave tank. Two papers, coauthored with Dr Magdalena and her students, are now in preparation.
Start Year 2018
 
Description Royal HaskoningDHV - beach sandscaping 
Organisation Royal HaskoningDHV
Country Netherlands 
Sector Private 
PI Contribution On Aug 21st, 2018 Prof Dodd and Prof Reeve met with a senior representative of Royal Haskong DHV at the University of Nottingham to discuss possible implementations of sandscaping solutions at various representative locations (i.e. scenarios). Discussions included the kinds of possible implementations, and the stability concept.
Collaborator Contribution We provided technical advice relating to sandscaping at Bacton.
Impact none to date
Start Year 2017
 
Description Visit to Universitat Politecnica de Catalunya, Dept of Applied Physics 
Organisation Polytechnic University of Catalonia
Department Department of Physics
Country Spain 
Sector Academic/University 
PI Contribution In a month-long visit to UPC, Barcelona, Dr Chen (Nottingham PDRA) studied the approach to linearization of the dynamical equations in a linear stability model (in particular, MORFO60). Dr Chen obtained the MORFO60 code from UPC, and learned how to compile and run the model. He became familiar with the input and output files of the model. For the purposes of verification Dr Chen then reproduced the results of the by Calvete et al (2005) [J. Geophys. Res., vol.110, C10006, doi:10.1029/2004JC002803] with the MORFO60 code. Dr Chen also subsequently discussed strategies with the members of the research group at UPC (associate professor, and full professor) and Prof Dodd and, for the implementation of the effect of tides into MORFO60. Both Dr Chen and Prof Dodd joined the field observation trip, organised by the research group, including a second associate professor, to Punta de la Banya to look at the development of nearshore seabed patterns. Prof Dodd also visited UPC for 1 week (funded by UPC) toward the end of Dr Chen's stay to participate in discussions, also with the group on related morphodynamics.
Collaborator Contribution The UPC research group provided the MORFO60 code. One member (associate professor) supervised Dr Chen during his studies on linear stability theory and on the implementation and use of the computational model MORFO60. The same asscociate professor also discussed with Dr Chen and Prof Dodd how to implement the effect of tides in the model. Another group member (professor) entered into discussions on this topic. The research group then organized the field observation trip to Punta de la Banya (see above). A second associate professor in the research group further discussed related topics of morphodynamics with Prof Dodd. The UPC research group also provided the funding for Prof Dodd to visit UPC for one week, toward the end of Dr Chen's stay, to participate in discussions (air fare and accommodation).
Impact Dr Chen has become as expert user of the MORFO60 model. He has begun to implement strategies for the inclusion of tides.
Start Year 2016
 
Description Attendance at sand-scaping meeting in London 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact The PIs of the MORPHINE project were invited to attend a meeting of scientist, engineers, and governmental representatives re the Bacton (Norfolk) sand-scaping project, which is planned to go ahead. This is a smaller-scale nourishment (compared to the Sand Engine on the Dutch coast). Dodd attended on behalf of the team. Results of observations and simulations of the Sand-Engine project were shown by a rep from Deltares. Discussions were had about how best to make scientific / engineering use of the Bacton intervention such that we can learn from it. A document was to be circulated to all attendees (including those invited but who couldn't attend) so as to summarise the meeting and plan possible actions. The meeting was held on 02.02.18 at UCL.
Year(s) Of Engagement Activity 2018
 
Description Invitation to give presentation on MORPHINE research at workshop at University of Da Nang, Vietnam 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Funding was obtained from the University of Nottingham, under the auspices of the Research Priority Area of Life in Changing Environments for a workshop to be held at the University of Da Nang - University of Science and Technology, Vietnam, on typhoon impacts on the Da Nang Bay region and the central Vietnam coast.
The aim was to combine coastal engineering and hydrodynamics, and sustainable flood risk management and assessment expertise, with local hydrology / fluvial flooding knowledge, to understand flood event dynamics; and to share experience from the Philippines and SE Asia region on disaster prevention and management. These synergies have potential to improve regional resilience to typhoons. As part of this Prof Dodd was invited by the local contact, Prof Vo Ngoc Duong, of the Facult of Water Resource Engineering, to present work on the MORPHINE project. The workshop is to be held on April 25-26, 2019.
Year(s) Of Engagement Activity 2019
URL http://wred.dut.udn.vn/icwrce/?fbclid=IwAR1anAJZVux57Qsn3PAnBYmOsGgvd0C2AUsw22ImCDlHwz8RaEpRgyuo5ao