Halcrow was commissioned to undertake a tidal and sediment transport study for the Cell 11 area (a sediment sub-cell along the coastal area of North Wales and North-West England) to run in parallel with, and in part inform, the development of the shoreline management plan review (SMP2) in that area.
The Cell Eleven Tidal and Sediment Transport Study (CETaSS) aimed to lead to a better understanding of the coastal processes including tidal currents, water levels, waves and sediment transport within the region, encompassing some 290km of open coast and 12 major estuaries and a number of minor ones.
CETaSS had the following objectives:
- To reduce uncertainty relating to coastal processes and specifically tidal currents and sediment transport;
- To provide coastal process information and understanding to improve the evidence base for selection of future flood and coastal erosion risk management (FCERM) policies in the Shoreline Management Plan and Strategy studies.
The following studies were undertaken as part of CETaSS:
- Regional tidal and sediment modelling - including offshore and littoral transport;
- Review of offshore banks - including characteristics and processes;
- Estuary Morphodynamics - including morphology, processes, past evolution, sediment supply and future behaviours;
- Assessment of coastal squeeze - including historical changes and likely future trends;
- Morecambe Bay studies - including sediment fluxes, sediment sink status, influences of estuaries, bank/channel systems, future morphological responses and coastal squeeze.
Aligned to CETaSS, a Joint Probability Study (JPS) was also carried out. The JPS aimed to produce consistent joint probability estimates for waves and water levels around the whole of the Cell 11 coastline to feed into subsequent studies. The JPS had the following objectives:
- To produce a review of available tide and wave information;
- To produce consistent joint probability estimates for waves and water levels for Cell 11.
- To provide consistent wave modelling around the Cell 11 shoreline that can be used to provide sufficient wave data to feed into assessments of regional littoral sediment transport budgets (part of the CETaSS study).