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The shingle (gravel) barrier beach at Pevensey Bay (East Sussex, UK) protects rare habitat, properties, trunk roads and other assets from flooding and erosion. The beach is managed in an adaptive manner by a private consortium, based on a 25 year contract. The practices developed at Pevensey are shown to fit into the frame of reference approach, adapted for the English policy and management framework. The barrier beach is managed to retain a favourable sediment status, although the concept has no official recognition, thereby ensuring that the barrier is sufficiently resilient to maintain its functions between interventions. The concept of favourable sediment status is considered a potentially useful way of summarising the status of the beach at Pevensey as it combines management objectives and processes (through coastal state indicators) with the availability of supply. The concept of the coastal sediment cell is important, but not sufficient, for identifying policy units at Pevensey as smaller-scale processes are also important. Two offshore dredging areas constitute the strategic sediment reservoir for Pevensey, although the term 'strategic sediment reservoir' has no official recognition and there is no long-term guarantee of supply.

Pevensey Coastal Defence Ltd has been managing the sea defences in Pevensey Bay, on the south coast of England, since June 2000. The public–private partnership sea defence scheme is a 25-year project to enhance and then maintain a mixed sand/shingle embankment that will provide protection against flooding and prevent breach of the bank from any storm up to 1:400 years. Providing the required standard of defence means ensuring sufficient shingle is on the beach, and that it is in the right place. This is achieved by monthly global positioning system monitoring surveys. Now, with data from over 100 surveys, there is evidence to suggest that fine sediment from the sand terrace below the embankment is being lost at a rate of around 8000 m3/year. This paper looks at possible natural and man-made reasons why this may occur, with a view to seeing whether this trend may be reversed or contained.

The Alba Field is contained within block 16/26 of the Central North Sea of the United Kingdom. This oil field was discovered in 1984 by Chevron UK Ltd with the 16/26–5 well and has been appraised by 16 wells and sidetracks. The field is currently being developed and is scheduled to achieve first production around the end of 1993. A 3-D seismic survey, acquired in 1989, has greatly enhanced delineation of the field. It is a NW-SE trending linear feature approximately 5.25 miles (8.5 kms) in length with adjacent satellite structures. The reservoir sands comprise the Nauchlan Member of the Alba Formation (Horda Group) and are primarily of Middle Eocene age. Gross sand thicknesses in excess of 400 ft (120 m) are present within the field area with porosities ranging up to 38% and permeabilities of the order of 2800 mD. The sands were deposited as a series of submarine channel fills whose mutual relationships present problems of detailed interpretation. Channel sandbodies appear to be discontinuous along their length for a variety of reasons including erosive relief on the base of the channel, and partial filling of channels otherwise filled by mud.

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