The design and impacts study look at the feasibility of the project in terms of potential impact, design of intervention and potential results.
Potential Impact: flooding of the site under various tidal conditions was modelled, and showed that the project would have a negligible effect on the tidal regime and coastal processes of Nigg Bay and the Cromarty Firth.
Design: different engineering options were considered - a single breach, two breaches, completely removing the sea wall or not doing anything. Hydraulic modelling informed the decision that two 20m breaches, lining up with the relic drainage channels, was the preferred design. It also specified some further engineering work.
Potential Results: the likely zonation of saltmarsh communities within the coastal realignment site was modelled, using the elevations of the site. This showed that there was sufficient topographical variation for a full zonation of saltmarsh communities to be restored without further engineering works.