Fieldwork in advance of sea defence construction from Brean Down towards Burnham provided the opportunity to examine deposits below the beach levels. Limited trenching and extensive sampling enabled the archaeological significance of these deposits to be established and this estuarine sequence to be related to the well-known archaeological sites and sequence within the terrestrial deposits exposed in the sand cliff. The research provided an opportunity for investigation of the wetland margin of the previously investigated, largely dryland, sand cliff environment. The results contribute to an understanding of the resources exploited from the prehistoric and Romano-British sites and has produced evidence of Romano-British drainage and agricultural activity on the levels.