The protection of the Happisburgh to Winterton coastal frontage – maintaining a sustainable approach despite long term uncertainty

The sea defences along the 14km coastline between Happisburgh to Winterton in North Norfolk protect a low-lying hinterland of which includes residential/commercial properties, internationally designated habitats, agricultural land and supports an important thriving tourism industry. Without the defences, a 1 in 1 year event alone, an area of 3,600 hectares would be flooded, including 1,256 hectares of the Broadland environmentally designated sites.

An initial Flood Defence Strategy was adopted in 1991 and then subsequently reviewed in 1996 and 2002. The management policy for this length of coastline has been the subject of on-going debate since 2004, and the longer-term (post 2055) Shoreline Management Plan (SMP) policy option is for “conditional hold the line, with an investigation into the potential for managed realignment, as and when it is confirmed that it is no longer sustainable to defend”.

The scheme was procured to secure the short to medium term future of the frontage, but there remains uncertainty around the long-term future. There is a need for an affordable, sustainable long-term solution delivered through a coherent strategy that also meets the needs of neighbouring areas. In developing this sustainable solution we need to consider the following:

• There is a degree of conflict between the need to protect inland environmental habitats from saline intrusion, and having a formal defence that could potentially affect the morphological and biodiversity features associated with a dynamic coastline and nationally significant dune habitat and heath;

• The frontage provides a gateway into the UK’s only wetland National Park; the Norfolk Broads. In addition to environmental impacts, there are considerable economic implications to areas ‘beyond’ the immediate coastal hinterland if actions required to provide sea defences are not carried out; and

• There are potential implications for the stability and sustainability of Winterton Ness if the Happisburgh to Winterton frontage is not held. The Ness is believed to exert an influence upon the offshore banks and channel and, should it move significantly or disappear, it could lead to changes in the offshore banks and currents and an accelerated erosion and re-orientation to the south.

This paper elaborates on these points; we explore how they influence the actions we are taking now and how we are moving forward to find the most appropriate engineering solutions to resolve the conflicts.